bluuebunny/crossref_metadata_2025 huggingface dataset:
Development of Multifunctional CoAl Based Layered Double Hydroxide Protective Film on Aluminum Alloy
Authors: Iqbal Muhammad Ahsan , Asghar Humaira , Fedel Michele
Published: December 2021

A protective CoAl-layered double hydroxide (LDH) thin film was developed directly on the aluminum substrate. Further, the low-surface-energy molecules (1H, 1H, 2H, 2H perfluorododecyl trichlorosilane) were incorporated inside the LDH network through an anion exchange mechanism to obtain a superhydrophobic CoAl-LDH surface. The developed films were characterized by scanning electron microscopy (SEM-EDS), X-ray diffraction (XRD), and Fourier transform infrared spectroscopy (FT-IR), and additional contact angle measurements were made to evaluate the superhydrophobicity of modified CoAl-LDHs against different solutions. The water contact angle (WCA) of the modified CoAl-LDH surface was observed to be about 153° and remained sufficiently stable after long-term immersion in NaCl solution. The effect of excessive ultrasonication on film structural variations and superhydrophobicity was also analyzed for outdoor applications. The high charge transfer resistance observed from the analysis of long-term electrochemical impedance spectroscopy (EIS) indicates the significant corrosion-resistance properties of the developed CoAl-LDHs. This research on protective CoAl-LDHs will bring insights into the understanding of new aspects of surface protection and implementation in many engineering applications.
Nanoscale Phase Separation of Incommensurate and Quasi-Commensurate Spin Stripes in Low Temperature Spin Glass of La2−xSrxNiO4
Authors: Campi Gaetano , Bianconi Antonio , Ricci Alessandro
Published: December 2021

While spin striped phases in La2−xSrxNiO4+y for 0.25 < x < 0.33 are the archetypal case of a 1D spin density wave (SDW) phase in doped antiferromagnetic strongly correlated perovskites, few information is available on the SDW spatial organization. In this context, we have measured the spatial variation of the wave vector of the SDW reflection profile by scanning micro X-ray diffractions with a coherent beam. We obtained evidence of a SDW order–disorder transition by lowering a high temperature phase (T > 50 K) to a low temperature phase (T < 50 K). We have identified quasi-commensurate spin stripe puddles in the ordered phase at 50 < T < 70 K, while the low temperature spin glassy phase presents a nanoscale phase separation of T = 30 K, with the coexistence of quasi-commensurate and incommensurate spin stripe puddles assigned to the interplay of quantum frustration and strong electronic correlations.
Out-of-Plane Sulfur Distortions in the Bi4O4S3 Superconductor
Authors: Philip Sharon S. , Athauda Anushika , Goto Yosuke , Mizuguchi Yoshikazu , Louca Despina
Published: December 2021

The local atomic structure of the non-magnetic layered superconductor Bi4O4S3 was investigated using neutron diffraction and pair density function (PDF) analysis. Although on average, the crystal structure is well ordered, evidence for local, out–of–plane sulfur distortions is provided, which may act as a conduit for charge transfer from the SO4 blocks into the superconducting BiS2 planes. In contrast with LaO1−xFxBiS2, no sulfur distortions were detected in the planes, which indicates that charge density wave fluctuations are not supported in Bi4O4S3.
Earthquake Impacts on the Livelihoods of Community Forest Users in Sindhupalchok District, Nepal, and Their Perceptions towards Forest Conservation
Authors: Adhikari Sudha , Harada Kazuhiro , Dahal Nabin Kumar , Kandel Saroj
Published: December 2021

Community forests are a crucial component of farming systems and people’s livelihoods in the rural middle hills of Nepal, where the population depends upon the forest for fuelwood, fodder, and leaf litter for their daily needs. This study aims to assess the perception of community forest user groups towards their postearthquake situations by using the five forms of capital from the sustainable livelihood framework. It further analyzes whether forest user’s attitudes towards forest conservation have changed or not. In addition to household interviews with 68 earthquake-affected households and extensive visits to the study area, key informant interviews and focus group discussions were conducted. This study confirms that the community forest user groups perceived negative effects on the natural, physical, human, and financial capitals, whereas they perceived a positive effect on social capital after the earthquake. Controlled access to forest products, such as timber collection during the recovery phase, restricted their resilience, although nontimber forest products supported it. Low agricultural production because of the scarcity of water for irrigation, as well as the soil infertility because of the landslides, caused local people to shift towards nonagricultural activities for income generation. Further, out-migration for job opportunities resulted in an inflow of remittances and, thus, manpower shortages were observed. Our results show that, despite facing the postdisaster impact on their livelihoods, 92% of the respondents were found to be positive towards forest conservation. This was because of their emotional attachment to the forest and the benefits received from the forest in the past. Local institutional policies and mechanisms must be strengthened to provide communities with the knowledge, skills, and practices for effective postdisaster recovery or for upcoming disasters, as well as the benefits of promoting sustainable forest conservation.
Apiaceae as an Important Source of Antioxidants and Their Applications
Authors: Thiviya Punniamoorthy , Gamage Ashoka , Piumali Dinushika , Merah Othmane , Madhujith Terrence
Published: December 2021

The excess level of reactive oxygen species (ROS) disturbs the oxidative balance leading to oxidative stress, which, in turn, causes diabetes mellites, cancer, and cardiovascular diseases. These effects of ROS and oxidative stress can be balanced by dietary antioxidants. In recent years, there has been an increasing trend in the use of herbal products for personal and beauty care. The Apiaceae (previously Umbelliferae) family is a good source of antioxidants, predominantly phenolic compounds, therefore, widely used in the pharmaceutical, cosmetic, cosmeceutical, flavor, and perfumery industries. These natural antioxidants include polyphenolic acids, flavonoids, carotenoids, tocopherols, and ascorbic acids, and exhibit a wide range of biological effects, including anti-inflammatory, anti-aging, anti-atherosclerosis, and anticancer. This review discusses the Apiaceae family plants as an important source of antioxidants their therapeutic value and the use in cosmetics.
Analysis of Fluoride Concentration in Toothpastes in the United Arab Emirates: Closing the Gap between Local Regulation and Practice
Authors: Jairoun Ammar , Al-Hemyari Sabaa , Shahwan Moyad , Jairoun Obaida , Zyoud Sa’ed
Published: December 2021

Background: While there is much scientific evidence supporting the benefits of fluoride for oral health, the concentration of fluoride in over-the-counter fluoride toothpaste should meet United Arab Emirates (UAE) regulations of a fluoride concentration not exceeding 0.15%. Objectives: The current study examines the fluoridated toothpaste products available on the UAE market and aims to quantify their total fluoride content. Methods: A total of 50 toothpaste products were collected and analyzed in this study. Ion Chromatography (IC) conductivity analysis was performed to determine the total fluoride content. Results: Among the 50 products tested, 10 exceeded the recommended concentration of total fluoride of less than 0.15%, while 12 had a total fluoride concentration that was less than was declared on their labels. Moreover, this study has revealed that 22 of the sampled products had a total fluoride concentration below 1000 ppm fluoride. An increased risk of higher total fluoride content was observed in the toothpaste products with monofluorophosphate active ingredients than in products with potassium nitrate/sodium fluoride and sodium fluoride (p = 0.011). Conclusions: There is a need to reassess the effectiveness of current regulations in the UAE to ensure that all fluoridated toothpastes available on the market are safe and effective for the consumer. Specifically, appropriate guidelines should be established on the basis of the risks and benefits inherent in fluoride exposure. Moreover, fluoridated toothpastes need to be subject to stricter monitoring and control regarding their safety and quality through good manufacturing practices (GMPs), education, research, and adverse event reporting.
The Analyses of High Infectivity Mechanism of SARS-CoV-2 and Its Variants
Authors: Lu Yonghua , Zhao Tianfu , Lu Ming , Zhang Yaopeng , Yao Xiang , Wu Guoyi , Dai Fangyin , Zhang Fengxiu , Zhang Guangxian
Published: December 2021

SARS-CoV-2 has high infectivity and some of its variants have higher transmissibility. To explore the high infectivity mechanism, the charge distributions of SARS-CoV, SARS-CoV-2, and variants of concern were calculated through a series of net charge calculation formulas. The results showed that the SARS-CoV-2 spike protein had more positive charges than that of SARS-CoV. Further results showed that the variants had similar but higher positive charges than preexisting SARS-CoV-2. In particular, the Delta variant had the greatest increase in positive charges in S1 resulting in the highest infectivity. In particular, the S1 positive charge increased greatly in the Delta variant. The S1 positive charge increased, and due to the large negative charge of angiotensin-converting enzyme-2 (ACE2), this resulted in a large increase in Coulomb’s force between S1 and ACE2. This finding agrees with the expectation that the positive charges in the spike protein result in more negative charges on SARS-CoV-2 antibodies than that of SARS-CoV. Thus, the infectivity of a novel SARS-CoV-2 variant may be evaluated preliminarily by calculating the charge distribution.
Impacts of the COVID-19 Pandemic on Children and Families from Marginalized Groups: A Qualitative Study in Kingston, Ontario
Authors: Lee Hannah , Bayoumi Imaan , Watson Autumn , Davison Colleen , Fu Minnie , Nolan Dionne , Mitchell Dan , Traviss Sheldon , Kehoe Jennifer , Purkey Eva
Published: December 2021

The COVID-19 pandemic has been associated with unprecedented changes to societal structure. School closures, unstable employment, and inaccessible health services have caused enormous disruptions to child and family wellbeing. This study identifies major themes illustrating how child and family wellness were impacted by COVID-19, including unique effects experienced by Indigenous families. In-depth interviews were conducted with key informants (n = 31) recruited from organizations providing healthcare and social services in Kingston, Ontario. Interview transcripts and written survey responses were analyzed using a phenomenological approach to explore themes related to child and family wellbeing. Three major themes identified include school closures, home safety, and outdoor spaces. School closures were generally reported as negatively impacting learning and social development; however, school closures allowed for some Indigenous children to be removed from a colonized education system, contributing to cultural and spiritual growth. Second, respondents reported increased severity and frequency of domestic violence, which negatively impacted child wellbeing. Third, the closure of public outdoor spaces created barriers to maintaining good physical health for children. This study recommends the prioritization of (1) child learning and development by avoiding school closures in pandemic settings and (2) the safety of Indigenous students by decolonizing education. To address the increased exposure to adverse childhood experiences (ACEs) during COVID-19, we recommend improved training for identifying and reporting domestic violence amongst service providers. Our study also reflects the broader need to redefine “essential services”, considering culturally specific services for Indigenous Peoples.
How to Implement Safe, Efficient and Cost-Effective SARS-CoV-2 Testing in Urban and Rural Schools within One Month
Authors: Kheiroddin Parastoo , Gründl Magdalena , Althammer Michael , Schöberl Patricia , Plail Linda , Cibali Ezgi , Schraml Kristina , Scheiber Josef , Kiesewetter Claudia , Kneissler Andreas , Bartl Christopher , Wallerstorfer Daniel , Barth Julien-Tyron , Rajabi Shabnam , Roth Cornelius , Matei Andreea , Fetz Christin , Buntrock-Döpke Heike , Gastiger Susanne , Bodenschatz Mona , Konrad Maike , Niggel Jakob , Pagel Philipp , Judex Guido , Hubmann Michael , Sweeney-Reed Catherine M. , Ambrosch Andreas , Wagner Thomas , Burkovski Andreas , Kabesch Michael
Published: December 2021

(1) Background: With vaccination and new variants of SARS-CoV-2 on the horizon, efficient testing in schools may enable prevention of mass infection outbreaks, keeping schools safe places and buying time until decisions on feasibility and the necessity of vaccination in children and youth are made. We established, in the course of the WICOVIR (Where Is the COrona VIRus) study, that gargle-based pool-PCR testing offers a feasible, efficient, and safe testing system for schools in Germany when applied by central university laboratories. (2) Objectives: We evaluated whether this approach can be implemented in different rural and urban settings. (3) Methods: We assessed the arrangements required for successful implementation of the WICOVIR approach in a variety of settings in terms of transport logistics, data transfer and pre-existing laboratory set-up, as well as the time required to establish the set-up. (4) Results: We found that once regulatory issues have been overcome, all challenges pertaining to logistics, data transfer, and laboratory testing on different platforms can be solved within one month. Pooling and depooling of samples down to the individual test result were achievable within one working day in all settings. Local involvement of the community and decentralized set-ups were keys for success. (5) Conclusion: The WICOVIR gargle-based pool-PCR system is so robust and simple that it can be implemented within one month in all settings now or in future pandemics.
Generalized Concatenated Codes over Gaussian and Eisenstein Integers for Code-Based Cryptography
Authors: Thiers Johann-Philipp , Freudenberger Jürgen
Published: December 2021

The code-based McEliece and Niederreiter cryptosystems are promising candidates for post-quantum public-key encryption. Recently, q-ary concatenated codes over Gaussian integers were proposed for the McEliece cryptosystem, together with the one-Mannheim error channel, where the error values are limited to the Mannheim weight one. Due to the limited error values, the codes over Gaussian integers achieve a higher error correction capability than maximum distance separable (MDS) codes with bounded minimum distance decoding. This higher error correction capability improves the work factor regarding decoding attacks based on information-set decoding. The codes also enable a low complexity decoding algorithm for decoding beyond the guaranteed error correction capability. In this work, we extend this coding scheme to codes over Eisenstein integers. These codes have advantages for the Niederreiter system. Additionally, we propose an improved code construction based on generalized concatenated codes. These codes extend to the rate region, where the work factor is beneficial compared to MDS codes. Moreover, generalized concatenated codes are more robust against structural attacks than ordinary concatenated codes.
Ammophila Invasion Ecology and Dune Restoration on the West Coast of North America
Authors: Pickart Andrea J.
Published: December 2021

The invasive ecosystem engineer Ammophila arenaria, native to Europe, was first introduced to California (USA) in 1896. More than a century later, it has come to dominate coastal foredune vegetation on the west coast of North America to the near exclusion of native species. A. arenaria builds a narrow, steep, peaked, and densely vegetated foredune, in contrast to the broad, more sparsely vegetated foredunes built by the native Elymus mollis. As such, it has modified dune processes by fixing the foredune and disrupting exchange of sediment between the beach, foredune, and dunefield. In the 1930s the congener A. breviligulata, native to the east coast and Great Lakes USA, was first introduced to Oregon, and has been displacing A. arenaria in southern Washington. Ammophila spp. have drastically reduced biodiversity, outcompeting native plant species, and displacing both invertebrate and vertebrate species. Restoration of west coast dunes through the removal of Ammophila began in the 1990s. Methods usually consist of one or a combination of manual digging, burning/herbicides, or excavation with heavy equipment. There are benefits and disadvantages to each method. Manual removal has proven most effective at restoring foredune form and process but is expensive. Excavation and herbicides may result in the loss of foredune morphology. Managers must articulate goals carefully before selecting restoration methods.
Factors Limiting the Range Extension of Corals into High-Latitude Reef Regions
Authors: Abrego David , Howells Emily J. , Smith Stephen D. A. , Madin Joshua S. , Sommer Brigitte , Schmidt-Roach Sebastian , Cumbo Vivian R. , Thomson Damian P. , Rosser Natalie L. , Baird Andrew H.
Published: December 2021

Reef-building corals show a marked decrease in total species richness from the tropics to high latitude regions. Several hypotheses have been proposed to account for this pattern in the context of abiotic and biotic factors, including temperature thresholds, light limitation, aragonite saturation, nutrient or sediment loads, larval dispersal constraints, competition with macro-algae or other invertebrates, and availability of suitable settlement cues or micro-algal symbionts. Surprisingly, there is a paucity of data supporting several of these hypotheses. Given the immense pressures faced by corals in the Anthropocene, it is critical to understand the factors limiting their distribution in order to predict potential range expansions and the role that high latitude reefs can play as refuges from climate change. This review examines these factors and outlines critical research areas to address knowledge gaps in our understanding of light/temperature interactions, coral-Symbiodiniaceae associations, settlement cues, and competition in high latitude reefs.
Development of A Spatiotemporal Database for Evolution Analysis of the Moscow Backbone Power Grid
Authors: Karpachevskiy Andrey , Titov German , Filippova Oksana
Published: December 2021

Currently in the field of transport geography, the spatial evolution of electrical networks remain globally understudied. Publicly available data sources, including remote sensing data, have made it possible to collect spatial data on electrical networks, but at the same time a suitable data structure for storing them has not been defined. The main purpose of this study was the collection and structuring of spatiotemporal data on electric networks with the possibility of their further processing and analysis. To collect data, we used publicly available remote sensing and geoinformation systems, archival schemes and maps, as well as other documents related to the Moscow power grid. Additionally, we developed a web service for data publication and visualization. We conducted a small morphological analysis of the evolution of the network to show the possibilities of working with the database using a Python script. For example, we found that the portion of new lines has been declining since 1950s and in the 2010s the portion of partial reconstruction reached its maximum. Thus, the developed data structure and the database itself provide ample opportunities for the analysis and interpretation of the spatiotemporal development of electric networks. This can be used as a basis to study other territories. The main results of the study are published on the web service where the user can interactively choose a year and two forms of power lines representation to visualize on a map.
Predicting Depression among Jordanian Adults with Disabilities According to the International Classification of Functioning, Disability and Health: A Pilot Study
Authors: Griffin Megan , Mitchell-Gillespie Bria , Hashim Hiba , AlHeresh Rawan
Published: December 2021

Individuals with disabilities face marginalization in society and are more likely to experience depression compared to the general population. Despite this, the health system in Jordan is not adequately equipped to screen for or manage depression as a comorbid condition. A pilot study using a cross-sectional design was used for this study. Eligible participants were between the ages of 18 and 85, had a physical disability and resided in Jordan. Depression was measured using the Patient Health Questionnaire-9, and risk factors were measured using a sociodemographic survey. Descriptive statistics were used to report on the prevalence of depression and Chi square and Kendall Tau B tests were used to identify relationships between independent variables and depression. The study found that 40.62% of the sample met the criteria for depression. Those who were not married were found to be at higher risk for depression. The analysis also demonstrated that the number of people in a household was positively correlated with depression. This study fills in gaps concerning the prevalence of depression and its correlates among Jordanian adults with a physical disability. Professionals in Jordan, including rehab specialists, have a role in both screening for and preventing depression, and this study acts as a point of reference for these professionals. This pilot study may initiate larger studies to better understand this relationship in Jordan.
The Importance of Collaboration in Pediatric Rehabilitation for the Construction of Participation: The Views of Parents and Professionals
Authors: Kinnunen Anu , Jeglinsky Ira , Vänskä Nea , Lehtonen Krista , Sipari Salla
Published: December 2021

Purpose: Collaboration between parents and professionals is essential to enable participation of children with disabilities. Participation is a widely researched topic in pediatric rehabilitation, and evidence for it providing opportunities for involvement and a sense of belonging in community and in larger society exists. There are, however, less research results on how collaboration builds participation pertaining to involvement in life situations. In collaboration with parents, therapists and teachers, the aim of the study was to describe factors that (a) promote and (b) prevent participation in life situations for school-aged children with disabilities, working towards participation in adulthood. Methods: The study applied a qualitative research design. The data was collected during the 2015–2016 academic year with five focus-group interviews by sampling procedure. The study involved five parents of children with disabilities, three therapists and two teachers. The research data was analyzed by inductive content analysis. Results: The results identified thirteen factors that promote child participation, with an emphasis on taking the child’s individuality into account. There were three barriers, which focused on attitudes or technical issues. Conclusions: The results suggest that collaboration on child-related factors has been well identified and implemented, but collaboration on enabling environmental factors needs to be developed. The results can be utilized to design what adults’ collaboration should focus on in promoting child participation.
Ageing and Obesity Shared Patterns: From Molecular Pathogenesis to Epigenetics
Authors: Ghanemi Abdelaziz , Yoshioka Mayumi , St-Amand Jonny
Published: December 2021

In modern societies, ageing and obesity represent medical challenges for healthcare professionals and caregivers. Obesity and ageing share common features including the related cellular and molecular pathways as well as the impacts they have as risk factors for a variety of diseases and health problems. Both of these health problems also share exercise and a healthy lifestyle as the best therapeutic options. Importantly, ageing and obesity also have common epigenetic changes (histone modification, DNA methylation, noncoding RNAs, and chromatin remodeling) that are also impacted by exercise. This suggests that epigenetic pathways are among the mechanisms via which exercise induces its benefits, including ageing and obesity improvements. Exploring these interrelations and based on the fact that both ageing and obesity represent risk factors for each other, would lead to optimizing the available therapeutic approaches towards improved obesity management and healthy ageing.
Micro versus Macro Shear Bond Strength Testing of Dentin-Composite Interface Using Chisel and Wireloop Loading Techniques
Authors: Ismail Ahmed M. , Bourauel Christoph , ElBanna Ahmed , Salah Eldin Tarek
Published: December 2021

Shear bond strength (SBS) testing is a commonly used method for evaluating different dental adhesive systems. Failure mode analysis provides valuable information for better interpretation of bond strength results. The aim of this study was to evaluate the influence of specimen dimension and loading technique on shear bond strength and failure mode results. Eighty macro and micro flowable composite cylindrical specimens of 1.8 and 0.8 mm diameter, respectively, and 1.5 mm length were bonded to dentinal substrate. Four study groups were created (n = 20): Macroshear wireloop, Gp1; Microshear wireloop, Gp2; Macroshear chisel, Gp3; and Microshear chisel, Gp4. They were tested for SBS using chisel and wireloop loading devices followed by failure mode analysis using digital microscopy and SEM. Two- and one-way ANOVA were used to compare stress at failure values of different groups while the Kruskal–Wallis test was used to compare between failure modes of the tested groups. Gp4 recorded the highest mean stress at failure 54.1 ± 14.1 MPa, and the highest percentage of adhesive failure in relation to the other groups. Specimen dimension and loading technique are important parameters influencing the results of shear bond strength. Micro-sized specimens and chisel loading are recommended for shear testing.
Using a Machine Learning Algorithm to Predict the Likelihood of Presence of Dental Caries among Children Aged 2 to 7
Authors: Ramos-Gomez Francisco , Marcus Marvin , Maida Carl A. , Wang Yan , Kinsler Janni J. , Xiong Di , Lee Steve Y. , Hays Ron D. , Shen Jie , Crall James J. , Liu Honghu
Published: December 2021

Background: Dental caries is the most common chronic childhood infectious disease and is a serious public health problem affecting both developing and industrialized countries, yet it is preventable in most cases. This study evaluated the potential of screening for dental caries among children using a machine learning algorithm applied to parent perceptions of their child’s oral health assessed by survey. Methods: The sample consisted of 182 parents/caregivers and their children 2–7 years of age living in Los Angeles County. Random forest (a machine learning algorithm) was used to identify survey items that were predictors of active caries and caries experience. We applied a three-fold cross-validation method. A threshold was determined by maximizing the sum of sensitivity and specificity conditional on the sensitivity of at least 70%. The importance of survey items to classifying active caries and caries experience was measured using mean decreased Gini (MDG) and mean decreased accuracy (MDA) coefficients. Results: Survey items that were strong predictors of active caries included parent’s age (MDG = 0.84; MDA = 1.97), unmet needs (MDG = 0.71; MDA = 2.06) and the child being African American (MDG = 0.38; MDA = 1.92). Survey items that were strong predictors of caries experience included parent’s age (MDG = 2.97; MDA = 4.74), child had an oral health problem in the past 12 months (MDG = 2.20; MDA = 4.04) and child had a tooth that hurt (MDG = 1.65; MDA = 3.84). Conclusion: Our findings demonstrate the potential of screening for active caries and caries experience among children using surveys answered by their parents.
Use of a Knowledge-Based Governance Approach to Plan a Post-COVID-19 Predoctoral Dental Curriculum
Authors: Flake Natasha , Chan Daniel , DiMarco Arthur , Silverstein Bruce
Published: December 2021

COVID-19 abruptly changed dental education, forcing educators out of their comfort zones and into using new technologies and teaching approaches. At the University of Washington School of Dentistry, a task force evaluated the curricular changes that resulted from COVID and made recommendations for the future predoctoral dental curriculum. This manuscript reports the process employed, the findings of the task force, and how these findings will impact the curriculum. A knowledge-based governance (KBG) approach was employed. KBG focuses on gathering all relevant information and identifying all choices. It separates dialogue from deliberation. Information was gathered via literature review, focus group interviews, electronic surveys, and other metrics. The task force evaluated: (1) delivering didactic content remotely; (2) administering assessments remotely; (3) duplicating preclinical simulation lab courses due to social distancing; and (4) the conversion from a numerical to a credit/no credit grading scale. Key recommendations resulted from focus groups and electronic surveys that allowed any student or faculty member an opportunity to provide input. Some topics were relatively non-controversial and strong recommendations were evident. The most controversial issue was which grading scale should be utilized. A KBG approach is an effective means to address mega issues in the dental school environment.
SORA Methodology for Multi-UAS Airframe Inspections in an Airport
Authors: Martinez Carol , Sanchez-Cuevas Pedro J. , Gerasimou Simos , Bera Abhishek , Olivares-Mendez Miguel A.
Published: December 2021

Deploying Unmanned Aircraft Systems (UAS) in safety- and business-critical operations requires demonstrating compliance with applicable regulations and a comprehensive understanding of the residual risk associated with the UAS operation. To support these activities and enable the safe deployment of UAS into civil airspace, the European Union Aviation Safety Agency (EASA) has established a UAS regulatory framework that mandates the execution of safety risk assessment for UAS operations in order to gain authorization to carry out certain types of operations. Driven by this framework, the Joint Authorities for Rulemaking on Unmanned Systems (JARUS) released the Specific Operation Risk Assessment (SORA) methodology that guides the systematic risk assessment for UAS operations. However, existing work on SORA and its applications focuses mainly on single UAS operations, offering limited support for assuring operations conducted with multiple UAS and with autonomous features. Therefore, the work presented in this paper analyzes the application of SORA for a Multi-UAS airframe inspection (AFI) operation, that involves deploying multiple UAS with autonomous features inside an airport. We present the decision-making process of each SORA step and its application to a multiple UAS scenario. The results shows that the procedures and safety features included in the Multi-AFI operation such as workspace segmentation, the independent multi-UAS AFI crew proposed, and the mitigation actions provide confidence that the operation can be conducted safely and can receive a positive evaluation from the competent authorities. We also present our key findings from the application of SORA and discuss how it can be extended to better support multi-UAS operations.
Spectrum Sensing Implemented with Improved Fluctuation-Based Dispersion Entropy and Machine Learning
Authors: Baldini Gianmarco , Chareau Jean-Marc , Bonavitacola Fausto
Published: December 2021

Spectrum sensing is an important function in radio frequency spectrum management and cognitive radio networks. Spectrum sensing is used by one wireless system (e.g., a secondary user) to detect the presence of a wireless service with higher priority (e.g., a primary user) with which it has to coexist in the radio frequency spectrum. If the wireless signal is detected, the second user system releases the given frequency to maintain the principle of not interfering. This paper proposes a machine learning implementation of spectrum sensing using the entropy measure as a feature vector. In the training phase, the information about the activity of the wireless service with higher priority is gathered, and the model is formed. In the classification phase, the wireless system compares the current sensing report to the created model to calculate the posterior probability and classify the sensing report into either the presence or absence of wireless service with higher priority. This paper proposes the novel application of the Fluctuation Dispersion Entropy (FDE) measure recently introduced in the research community as a feature vector to build the model and implement the classification. An improved implementation of the FDE (IFDE) is used to enhance the robustness to noise. IFDE is further enhanced with an adaptive method (AIFDE) to automatically select the hyper-parameter introduced in IFDE. Then, this paper combines the machine learning approach with the entropy measure approach, which are both recent developments in spectrum sensing research. The approach is compared to similar approaches in literature and the classical energy detection method using a generated radar signal data set with different conditions of SNR(dB) and fading conditions. The results show that the proposed approach is able to outperform the approaches from literature based on other entropy measures or the Energy Detector (ED) in a consistent way across different levels of SNR and fading conditions.
Crash Diagnosis and Price Rebound Prediction in NYSE Composite Index Based on Visibility Graph and Time-Evolving Stock Correlation Network
Authors: Xiu Yuxuan , Wang Guanying , Chan Wai Kin Victor
Published: December 2021

This study proposes a framework to diagnose stock market crashes and predict the subsequent price rebounds. Based on the observation of anomalous changes in stock correlation networks during market crashes, we extend the log-periodic power-law model with a metric that is proposed to measure network anomalies. To calculate this metric, we design a prediction-guided anomaly detection algorithm based on the extreme value theory. Finally, we proposed a hybrid indicator to predict price rebounds of the stock index by combining the network anomaly metric and the visibility graph-based log-periodic power-law model. Experiments are conducted based on the New York Stock Exchange Composite Index from 4 January 1991 to 7 May 2021. It is shown that our proposed method outperforms the benchmark log-periodic power-law model on detecting the 12 major crashes and predicting the subsequent price rebounds by reducing the false alarm rate. This study sheds light on combining stock network analysis and financial time series modeling and highlights that anomalous changes of a stock network can be important criteria for detecting crashes and predicting recoveries of the stock market.
Cities and Climate Change
Authors: Short John Rennie , Farmer Abbey
Published: December 2021

This review paper considers the disjuncture between the rapid pace of climate change and the more sluggish ability of cities to fully implement effective strategies of climate change adaptation and mitigation. We will refer to this as the ‘slow city–quick climate change’ dilemma. Climate change is accelerating, quickly rendering obsolete previous urban forms inadequate, while structural adjustments to cities are slower moving. Cities around the world were largely built for previous climate regimes. In the short to medium term, there is a mismatch between the climate regime that cities were designed for and the climate regime they now inhabit. The paper is divided into four parts: a brief review of climate change in general; climate change in cities; a review of climate change adaptation and mitigation in cities; and finally, a discussion of urban futures in the time of climate regime change.
Accuracy of Image-Based Automated Diagnosis in the Identification and Classification of Acute Burn Injuries. A Systematic Review
Authors: Boissin Constance , Laflamme Lucie
Published: December 2021

Although they are a common type of injury worldwide, burns are challenging to diagnose, not least by untrained point-of-care clinicians. Given their visual nature, developments in artificial intelligence (AI) have sparked growing interest in the automated diagnosis of burns. This review aims to appraise the state of evidence thus far, with a focus on the identification and severity classification of acute burns. Three publicly available electronic databases were searched to identify peer-reviewed studies on the automated diagnosis of acute burns, published in English since 2005. From the 20 identified, three were excluded on the grounds that they concerned animals, older burns or lacked peer review. The remaining 17 studies, from nine different countries, were classified into three AI generations, considering the type of algorithms developed and the images used. Whereas the algorithms for burn identification have not gained much in accuracy across generations, those for severity classification improved substantially (from 66.2% to 96.4%), not least in the latest generation (n = 8). Those eight studies were further assessed for methodological bias and results applicability, using the Quality Assessment of Diagnostic Accuracy Studies (QUADAS-2) tool. This highlighted the feasibility nature of the studies and their detrimental dependence on online databases of poorly documented images, at the expense of a substantial risk for patient selection and limited applicability in the clinical setting. In moving past the pilot stage, future development work would benefit from greater input from clinicians, who could contribute essential point-of-care knowledge and perspectives.
A Thoughtful Insight on Women Entrepreneur’s Investment Attitude
Authors: Hussain Batool Muhammad , Baig Umair , Davidaviciene Vida , Meidute-Kavaliauskiene Ieva
Published: December 2021

This study endeavors to be cognizant of the investment paradigm of women entrepreneurs and reveal their ambitions, professionalism, and desire to form a robust framework in the context of economic development. These persistent attributes of women entrepreneurs for economic development persuaded us to investigate factors that influence women’s attitude to make a long-term investment decision in their business regardless of uncertainty. This study adopted a deductive approach and assessed data using the PLS-SEM technique through Smart PLS 3.3.3. Around 330 adequate responses from Karachi and Lahore using a self-designed structured questionnaire revealed that women’s investment attitude has a positive significant mediating effect on social, behavioral factors, and investment decisions. Whereas, women’s investment attitude did not depict a positive significant mediating effect on personal factors and investment decisions. It was quite interesting to know that uncertainty did not reveal a significant moderating effect between investment attitude and investment decision. The study highlights measures suggested empowering women entrepreneurs who strive to enhance their performance and achieve sustainable development goals without being discouraged by society. Moreover, focusing risk-taking attributes to set an example for those who do not come forth. The novelty of the study in the context of women entrepreneur’s investment attitude well contributes to the existing literature and recommends future scholars to expand the horizon of the existing area of the study in the context of cultural, demographic, and seasonal factors, which are also affecting women entrepreneur’s investment decisions.
Lost and Found—Unfolding and Refolding Aesthetic Learning Processes
Authors: Hellman Annika , Lind Ulla
Published: December 2021

The ongoing marketisation of education is a great loss for visual arts education since explorative learning processes are marginalised in favour of more goal-oriented learning. The empirical material analysed in this research derives from the visual art portfolio of a student from an elective university course in visual arts education. Working within Deleuze and Guattari’s philosophical framework, we examine the folding, unfolding, and refolding of aesthetic learning processes, suggesting productive concepts and practices. The analysis made us aware of our own pedagogical ideals and the loss of having to disassemble them, in line with the new curricula. The student’s visual learning process showed us how to reassemble new and explorative learning processes, assigning aspects of sustainability and an ethics of care in relation to environmental and social questions. We suggest strategies for learning in the folds, where educators are called upon to prepare students for an uncertain future. This demands a creative imagination, an ethical standpoint for negotiating the curriculum in line with differentiation by forming, inventing, and fabricating new concepts and images.
Internal Tensions of Building a Dissertation through the Lens of Black Finesse: Toward Decolonizing Higher Education
Authors: Mackey Janiece Zalina
Published: December 2021

In this paper, I focus on the process of building a dissertation that honored the Black souls of my undergraduate participants along with my own Black soul as a form of resistance to advance racial equity in higher education. Through endarkened narrative inquiry, this paper will address the internal tensions I navigated in building a dissertation that centered Blackness through the prism of what I have conceptualized as Black Finesse. I unveil components from my dissertation that manifested a shift in how knowledge generation can be developed and written. I conceptualized a methodology entitled race-grounded phenomenology (RGP) and call for a re-imagining of qualitative research around the ways Black students navigate higher education. I reflected upon the internal tensions and mental leaps of my dissertation process through theoretical decolonial inquiry. As decolonial praxis to unmake the canon of research and dissertation creation, I lean upon four elements of decolonizing higher education as a way to reimagine decolonial futures that were actualized via my dissertation process.
Smart Working and Well-Being before and during the COVID-19 Pandemic: A Scoping Review
Authors: Marino Leda , Capone Vincenza
Published: December 2021

The purpose of this scoping review focused on the relationship between smart working, a conception of job centered on the flexibility and autonomy of the worker, and well-being/illness in an organizational context before and during COVID-19. The literature review, conducted using the PRISMA (Preferred Reporting Items for Systematic Review and Meta-Analysis for qualitative synthesis) method for qualitative synthesis, considered studies published from 2014 to 2020. From the analyses conducted by three independent coders, three main areas of interest in the literature emerged: (1) smart working and work engagement, (2) smart working and technostress, and (3) mediators of the relationship between smart working and well-being. The review highlights the need for an organizational culture increasingly oriented towards agile working practices in conjunction with organizational support and training.
Optimal Stochastic Computing Randomization
Authors: Frasser Christiam F. , Roca Miquel , Rosselló Josep L.
Published: December 2021

Stochastic computing (SC) is a probabilistic-based processing methodology that has emerged as an energy-efficient solution for implementing image processing and deep learning in hardware. The core of these systems relies on the selection of appropriate Random Number Generators (RNGs) to guarantee an acceptable accuracy. In this work, we demonstrate that classical Linear Feedback Shift Registers (LFSR) can be efficiently used for correlation-sensitive circuits if an appropriate seed selection is followed. For this purpose, we implement some basic SC operations along with a real image processing application, an edge detection circuit. Compared with the literature, the results show that the use of a single LFSR architecture with an appropriate seeding has the best accuracy. Compared to the second best method (Sobol) for 8-bit precision, our work performs 7.3 times better for the quadratic function; a 1.5 improvement factor is observed for the scaled addition; a 1.1 improvement for the multiplication; and a 1.3 factor for edge detection. Finally, we supply the polynomials and seeds that must be employed for different use cases, allowing the SC circuit designer to have a solid base for generating reliable bit-streams.
Floating Offshore Vertical Axis Wind Turbines: Opportunities, Challenges and Way Forward
Authors: Arredondo-Galeana Abel , Brennan Feargal
Published: December 2021

The offshore wind sector is expanding to deep water locations through floating platforms. This poses challenges to horizontal axis wind turbines (HAWTs) due to the ever growing size of blades and floating support structures. As such, maintaining the structural integrity and reducing the levelised cost of energy (LCoE) of floating HAWTs seems increasingly difficult. An alternative to these challenges could be found in floating offshore vertical axis wind turbines (VAWTs). It is known that VAWTs have certain advantages over HAWTs, and in fact, some small-scale developers have successfully commercialised their onshore prototypes. In contrast, it remains unknown whether VAWTs can offer an advantage for deep water floating offshore wind farms. Therefore, here we present a multi-criteria review of different aspects of VAWTs to address this question. It is found that wind farm power density and reliability could be decisive factors to make VAWTs a feasible alternative for deep water floating arrays. Finally, we propose a way forward based on the findings of this review.