bluuebunny/crossref_metadata_2025 huggingface dataset:
Parametric Sensitivity Analysis of Rotor Angle Stability Indicators
Authors: Shrestha Ashish , Gonzalez-Longatt Francisco
Published: August 2021

With the increasing penetration rate of Power Electronic Converter (PEC) based technologies, the electrical power systems are facing the problem of transient stability since the PEC based technologies do not contribute to the system inertia, and the proportion of synchronous generators (i.e., the source of inertia) is in decreasing rate. In addition, PEC based technologies’ components have poor inherent damping. It is very important to analyze the system characteristics of a power system to minimize the potential instabilities during the contingencies. This paper presents the parametric sensitivity analysis of the rotor angle stability indicators for the 39-bus New England power system. The indicators of rotor angle stability analysis such as critical fault clearing time (CCT), Eigenvalue points, damping ratio, frequency deviation, voltage deviation, and generator’s speed deviation are identified and analyzed for three case scenarios; each scenario has six sub-cases with different inertia constants. The results show that the CCTs for each component will be reduced if the inertia reduces at any section of a multi-machine power system. Although the applied three scenarios with six sub-cases are identified to be stable in this analysis, the decreasing inertia constant has significant impact on the power system dynamics.
Performance of the XMPP and the MQTT Protocols on IEC 61850-Based Micro Grid Communication Architecture
Authors: Jun Hyun-Ji , Yang Hyo-Sik
Published: August 2021

As micro grids are gradually being deployed in many areas, communication technology is becoming important for collecting data and controlling devices in micro grids. In a micro grid, various devices are distributed and perform their respective functions. These devices exchange information with each other and transmit information to the micro grid management system. This micro grid environment is similar to the IoT environment in which information is exchanged in the presence of a large number of devices. Recent studies have tried to apply various IoT protocols as a communication protocol in the micro grid. However, the data model used in current research is limited in proprietary data mapping. Recently, IEC TC 57 published another IEC 61850 series which maps the IEC 61850 services to XMPP (eXtensible Messaging Presence Protocol), which was the first IoT protocol mapping of IEC 61850. Few research has shown that the mapping of the IEC 61850 data model to the IoT protocol and communication boundary is limited in a lab environment. We developed a micro grid test-bed with an IEC 61850 data and service model, and mapped to two IoT protocols, that is, XMPP and the MQTT (Message Queuing Telemetry Transport). By combining IoT protocol with the IEC 61850 data and service model, the proposed micro grid architecture can provide interoperability with any DMS or other power utility system. Performance analysis was conducted on the test-bed by measuring various metrics, such as the response time, packet size, and packet loss, over a public network.
Induction Motor Direct Torque Control with Synchronous PWM
Authors: Benevieri Alessandro , Maragliano Gianmarco , Marchesoni Mario , Passalacqua Massimiliano , Vaccaro Luis
Published: August 2021

A novel induction motor direct torque control (DTC) algorithm with synchronous modulation is presented. Compared to the traditional DTC method, whose main drawback is the presence of low-frequency torque harmonics (sub-harmonics), in the proposed method, the PWM switching frequency is imposed to be an integer multiple of the main supply frequency. This is achieved by continuously adjusting the PWM switching period to significantly reduce low-frequency harmonics. The devised algorithm has been tested on an inverter-fed induction motor drive system, and the obtained results show an important reduction of the sub-harmonic spectral content of the developed torque with respect to a conventional direct torque control while maintaining at the same time a high dynamic response.
Energy Management Systems for Grid-Connected Houses with Solar PV and Battery by Considering Flat and Time-of-Use Electricity Rates
Authors: Pan Xincheng , Khezri Rahmat , Mahmoudi Amin , Yazdani Amirmehdi , Shafiullah GM
Published: August 2021

This paper develops new practical rule-based energy management systems (EMSs) for typical grid-connected houses with solar photovoltaic (PV) and battery by considering different rates for purchasing and selling electricity. The EMSs are developed to supply the household’s loads and reduce operating costs of the system based on different options of flat and time-of-use (ToU) rates for buying and selling electricity prices. Four different options are evaluated and compared in this study: (1) Flat-Flat, (2) ToU-Flat, (3) Flat-ToU, and (4) ToU-ToU. The operation cost is calculated based on the electricity exchange with the main grid, the equivalent cost of PV generation, as well as the degradation cost of battery storage. The operation of the grid-connected house with rooftop solar PV and battery is evaluated for a sunny week in summer and a cloudy week in winter to investigate the proper performance for high and low generations of PV. While the developed rule-based EMS are generic and can be applied for any case studies, a grid-connected house in Australia is examined. For this purpose, real data of solar radiation, air temperature, electricity consumption, and electricity rates are used. It is found that the ToU-Flat option has the lowest operating cost for the customers.
The Effect of Ammonia Toxicity on Methane Production of a Full-Scale Biogas Plant—An Estimation Method
Authors: Kalamaras Sotirios D. , Vitoulis Georgios , Christou Maria Lida , Sfetsas Themistoklis , Tziakas Spiridon , Fragos Vassilios , Samaras Petros , Kotsopoulos Thomas A.
Published: August 2021

Ammonia accumulation in biogas plants reactors is becoming more frequently encountered, resulting in reduced methane (CH4) production. Ammonia toxicity occurs when N-rich substrates represent a significant part of the biogas plant’s feedstock. The aim of this study was to develop an estimation method for the effect of ammonia toxicity on the CH4 production of biogas plants. Two periods where a biogas plant operated at 3200 mg·L−1 (1st period) and 4400 mg·L−1 (2nd period) of ammonium nitrogen (NH4+–N) were examined. Biomethane potentials (BMPs) of the individual substrates collected during these periods and of the mixture of substrates with the weight ratio used by the biogas plant under different ammonia levels (2000–5200 mg·L−1 NH4+–N) were determined. CH4 production calculated from the substrates’ BMPs and the quantities used of each substrate by the biogas plant was compared with actual CH4 production on-site. Biogas plant’s CH4 production was 9.9% lower in the 1st and 20.3% in the 2nd period in comparison with the BMP calculated CH4 production, of which 3% and 14% was due to ammonia toxicity, respectively. BMPs of the mixtures showed that the actual CH4 reduction rate of the biogas plant could be approximately estimated by the ammonia concentrations levels.
Knowledge Integration in Smart Factories
Authors: Zenkert Johannes , Weber Christian , Dornhöfer Mareike , Abu-Rasheed Hasan , Fathi Madjid
Published: August 2021

Knowledge integration is well explained by the human–organization–technology (HOT) approach known from knowledge management. This approach contains the horizontal and vertical interaction and communication between employees, human-to-machine, but also machine-to-machine. Different organizational structures and processes are supported with the help of appropriate technologies and suitable data processing and integration techniques. In a Smart Factory, manufacturing systems act largely autonomously on the basis of continuously collected data. The technical design concerns the networking of machines, their connectivity and the interaction between human and machine as well as machine-to-machine. Within a Smart Factory, machines can be considered as intelligent manufacturing systems. Such manufacturing systems can autonomously adapt to events through the ability to intelligently analyze data and act as adaptive manufacturing systems that consider changes in production, the supply chain and customer requirements. Inter-connected physical devices, sensors, actuators, and controllers form the building block of the Smart Factory, which is called the Internet of Things (IoT). IoT uses different data processing solutions, such as cloud computing, fog computing, or edge computing, to fuse and process data. This is accomplished in an integrated and cross-device manner.
Single-Use Plastic Bans: Exploring Stakeholder Perspectives on Best Practices for Reducing Plastic Pollution
Authors: Cowan Emily , Booth Andy M. , Misund Andreas , Klun Katja , Rotter Ana , Tiller Rachel
Published: August 2021

In this study, we conducted and documented workshops and interviews in Norway and Slovenia to identify stakeholder and future generation opinions and mitigation strategies for solving one of the most prominent environmental issues: plastic pollution. As part of the EU H2020 project GoJelly, stakeholders were brought together to explore their perceptions on considering jellyfish mucus as a new resource to contribute to reducing plastic pollution from entering the marine environment. The study was conducted in the spring of 2019, in a context directly after the European Union (EU) announced its Directive to ban the most commonly used single-use plastic (SUP) items. The study applied the snowball method as a methodological choice to identify relevant stakeholders. Systems thinking was utilized as a participatory modelling approach, which allowed for the creation of conceptual mind maps from the various workshops and interviews, to understand consumers’ consciousness, and to map out ideas on plastic pollution reduction. Plastic pollution takes place on a global scale and stakeholders discussed their individual perceptions of national and international solutions that could be put in place to solve it, including the opportunities around utilizing jellyfish mucus to filter and capture micro- and nanoplastic. We found that industry stakeholders in both case areas were generally more accepting of policy and increased innovation moving forward, but placed weight on the scientific community to conduct more research on the pollution issue and propose solutions. Future generation stakeholders (youth aged 14–18), however, put emphasis on consumer behavior and buying patterns of single-use products fueling the plastic crisis.
Methods for Measuring Frost Tolerance of Conifers: A Systematic Map
Authors: Atucha Zamkova Anastasia-Ainhoa , Steele Katherine A. , Smith Andrew R.
Published: August 2021

Frost tolerance is the ability of plants to withstand freezing temperatures without unrecoverable damage. Measuring frost tolerance involves various steps, each of which will vary depending on the objectives of the study. This systematic map takes an overall view of the literature that uses frost tolerance measuring techniques in gymnosperms, focusing mainly on conifers. Many different techniques have been used for testing, and there has been little change in methodology since 2000. The gold standard remains the field observation study, which, due to its cost, is frequently substituted by other techniques. Closed enclosure freezing tests (all non-field freezing tests) are done using various types of equipment for inducing artificial freezing. An examination of the literature indicates that several factors have to be controlled in order to measure frost tolerance in a manner similar to observation in a field study. Equipment that allows controlling the freezing rate, frost exposure time and thawing rate would obtain results closer to field studies. Other important factors in study design are the number of test temperatures used, the range of temperatures selected and the decrements between the temperatures, which should be selected based on expected frost tolerance of the tissue and species.
High Diversity of Mites (Acari: Oribatida, Mesostigmata) Supports the High Conservation Value of a Broadleaf Forest in Eastern Norway
Authors: Seniczak Anna , Seniczak Stanisław , Starý Josef , Kaczmarek Sławomir , Jordal Bjarte H. , Kowalski Jarosław , Roth Steffen , Djursvoll Per , Bolger Thomas
Published: August 2021

Broadleaf forests are critical habitats for biodiversity and this biodiversity is in turn essential for their proper functioning. Mites (Acari) are a numerous and functionally essential component of these forests. We report the diversity of two important groups, Oribatida and Mesostigmata, in a broadleaf forest in Eastern Norway which is considered to be a biodiversity hotspot. Eighteen samples, each 500 cm3, were collected from diverse microhabitats (moss on ground, lichens on tree twigs lying on ground, moss on tree trunks at ground level, moss on tree trunks 1.5 m above ground, moss on decaying stump, moss on decaying log, and decaying wood from trees) from which 10,843 specimens and 95 species from 32 families of Oribatida, and 655 specimens of 34 species from 14 families of Mesostigmata were found. Only 30% of the species were previously recorded in broadleaf forests in Western Norway. Oribatid communities on decaying stump and in lichens were distinct from the other communities, while mesostigmatid communities on tree trunks (both at ground level and 1.5 m above ground) and in lichens differed most from other communities. Over 30% of the species were found in only a single microhabitat. Twenty-three species and the genus Zerconopsis are reported from Norway for the first time. Six records are also new to Fennoscandia, including (Oribatida) Coronoquadroppia monstruosa, Eueremaeus valkanovi, Ramusella furcata, and (Mesostigmata) Dendrolaelaps rectus, D. multidentatus, and D. tenuipilus. In addition, several rare species were detected, e.g., Achipteria magna, Oribotritia berlesei, and Subiasella quadrimaculata, and two were found in their northernmost locality (O. berlesei, E. valkanovi). These results confirm the unique character and high conservation value of the studied forest in Norway, Fennoscandia and at a European scale.
Influence of Cultivation pH on Composition, Diversity, and Metabolic Production in an In Vitro Human Intestinal Microbiota
Authors: Haindl Regina , Schick Simon , Kulozik Ulrich
Published: August 2021

Fecal microbiota transplantation, an alternative treatment method for gastrointestinal diseases, has a high recovery rate, but comes with disadvantages, such as high donor requirements and the low storability of stool. A solution to overcome these problems is the cultivation of an in vitro microbiota. However, the influence of cultivation conditions on the pH are yet unknown. In this study, the influence of the cultivation pH (6.0–7.0) on the system’s behavior and characteristics, including cell count, metabolism, and microbial composition, was investigated. With an increasing cultivation pH, an increase in cell count, total amount of SCFAs, acetate, propionate, and the abundance of Bacteroidetes and Verrucomicrobia were observed. For the concentration of butyrate and the abundance of Actinobacteria and Firmicutes, a decrease with increasing pH was determined. For the concentration of isovalerate, the abundance of Proteobacteria and diversity (richness and Shannon effective), no effect of the pH was observed. Health-promoting genera were more abundant at lower pH levels. When cultivating an in vitro microbiota, all investigated pH values created a diverse and stable system. Ultimately, therefore, the choice of pH creates significant differences in the established in vitro microbiota, but no clear recommendations for a special value can be made.
Correlation between Large-Scale Streamwise Velocity Features and the Height of Coherent Vortices in a Turbulent Boundary Layer
Authors: Shrivastava Shaurya , Saxton-Fox Theresa
Published: August 2021

The preferential organisation of coherent vortices in a turbulent boundary layer in relation to local large-scale streamwise velocity features was investigated. Coherent vortices were identified in the wake region using the Triple Decomposition Method (originally proposed by Kolář) from 2D particle image velocimetry (PIV) data of a canonical turbulent boundary layer. Two different approaches, based on conditional averaging and quantitative statistical analysis, were used to analyze the data. The large-scale streamwise velocity field was first conditionally averaged on the height of the detected coherent vortices and a change in the sign of the average large scale streamwise fluctuating velocity was seen depending on the height of the vortex core. A correlation coefficient was then defined to quantify this relationship between the height of coherent vortices and local large-scale streamwise fluctuating velocity. Both of these results indicated a strong negative correlation in the wake region of the boundary layer between vortex height and large-scale velocity. The relationship between vortex height and full large-scale velocity isocontours was also studied and a conceptual model based on the findings of the study was proposed. The results served to relate the hairpin vortex model of Adrian et al. to the scale interaction results reported by Mathis et al., and Chung and McKeon.
Cutting-Edge Turbulence Simulation Methods for Wind Energy and Aerospace Problems
Authors: Heinz Stefan , Peinke Joachim , Stoevesandt Bernhard
Published: August 2021

The availability of reliable and efficient turbulent flow simulation methods is highly beneficial for wind energy and aerospace developments. However, existing simulation methods suffer from significant shortcomings. In particular, the most promising methods (hybrid RANS-LES methods) face divergent developments over decades, there is a significant waste of resources and opportunities. It is very likely that this development will continue as long as there is little awareness of conceptional differences of hybrid methods and their implications. The main purpose of this paper is to contribute to such clarification by identifying a basic requirement for the proper functioning of hybrid RANS-LES methods: a physically correct communication of RANS and LES modes. The state of the art of continuous eddy simulations (CES) methods (which include the required mode communication) is described and requirements for further developments are presented.
Loop Current SSH Forecasting: A New Domain Partitioning Approach for a Machine Learning Model
Authors: Wang Justin L. , Zhuang Hanqi , Chérubin Laurent , Muhamed Ali Ali , Ibrahim Ali
Published: August 2021

A divide-and-conquer (DAC) machine learning approach was first proposed by Wang et al. to forecast the sea surface height (SSH) of the Loop Current System (LCS) in the Gulf of Mexico. In this DAC approach, the forecast domain was divided into non-overlapping partitions, each of which had their own prediction model. The full domain SSH prediction was recovered by interpolating the SSH across each partition boundaries. Although the original DAC model was able to predict the LCS evolution and eddy shedding more than two months and three months in advance, respectively, growing errors at the partition boundaries negatively affected the model forecasting skills. In the study herein, a new partitioning method, which consists of overlapping partitions is presented. The region of interest is divided into 50%-overlapping partitions. At each prediction step, the SSH value at each point is computed from overlapping partitions, which significantly reduces the occurrence of unrealistic SSH features at partition boundaries. This new approach led to a significant improvement of the overall model performance both in terms of features prediction such as the location of the LC eddy SSH contours but also in terms of event prediction, such as the LC ring separation. We observed an approximate 12% decrease in error over a 10-week prediction, and also show that this method can approximate the location and shedding of eddy Cameron better than the original DAC method.
Nonlinear Dynamic Analysis of a Masonry Arch Bridge Accounting for Damage Evolution
Authors: Addessi Daniela , Gatta Cristina , Nocera Mariacarla , Liberatore Domenico
Published: August 2021

This study investigates the nonlinear dynamic response of the masonry bridge ‘Ponte delle Torri’ in Spoleto, aiming at assessing the seismic performance of the structure and evaluating the occurring damaging mechanisms. A 3D Finite Element (FE) macromechanical procedure implemented in the FE program FEAP is adopted to model the bridge. To reproduce the typical nonlinear microcracking process evolving in masonry material when subjected to external loads, an isotropic damage model is used. This is based on a scalar damage variable introduced in the stress-strain constitutive law and equally degrading all the components of the elastic constitutive operator. A nonlocal integral definition of the damage associated variable, that is the equivalent strain measure governing its evolution, is adopted to overcome the mesh dependency problems of the FE solution typically occurring in the presence of strain softening behavior. Based on the results of a recent study by some of the authors, a single equivalent pier is analyzed, whose geometry and boundary conditions are selected so that its response can provide useful information on the out-of-plane dynamic behavior of the overall bridge. To perform the seismic assessment, a set of recorded accelerograms is properly selected to simulate the seismic history of the Spoleto site. The nonlinear dynamic response of the structure is evaluated and monitored in terms of top displacement time history, evolution of the global damage index, and distribution of the damage variable. First, a set of analyses is performed by imposing the selected ground motions one by one on the initial undamaged configuration for the structure with the aim of emphasizing the damaging effects on its dynamic response. Then, the accelerograms are arranged in sequence to reproduce the seismic history of the site and analyze the influence of accumulated damage on the dynamic amplification of the response. A critical comparison of the bridge response to the sequence of accelerograms and the single records is made, and the interaction between the damaged structure dynamic response and the signal characteristic is highlighted, as well.
Force Production and Coordination from Older Women in Water Fitness Exercises
Authors: Santos Catarina C. , Marinho Daniel A. , Faíl Luís B. , Neiva Henrique P. , Costa Mário J.
Published: August 2021

The aim of this study was to compare bilateral propulsive forces and coordination while exercising at static and dynamic conditions in the water. A total of 27 older women (age: 65.1 ± 6.7 years old) performed the following exercises: (i) horizontal upper-limbs adduction (HA; static condition) and (ii) rocking horse (RH; dynamic condition) through an incremental protocol with music cadences from 105 up to 150 b·min−1. The duration of each trial was set at 30 second (sec). Propulsive peak force (in Newton, N) of dominant (PFD) and nondominant (PFND) upper limbs was retrieved using hand sensors coupled to a differential pressure system. Significant differences in force production were found between static and dynamic exercises at higher cadences (120, 135, and 150 b·min−1). The static condition elicited higher bilateral propulsive forces and a more symmetric pattern. The in-water static exercise with bilateral action from the upper limbs proved to be the most appropriate strategy for older women to work strength and to reduce asymmetries.
Dyes of a Shadow Theatre: Investigating Tholu Bommalu Indian Puppets through a Highly Sensitive Multi-Spectroscopic Approach
Authors: Ciccola Alessandro , Serafini Ilaria , D'Agostino Giulia , Giambra Belinda , Bosi Adele , Ripanti Francesca , Nucara Alessandro , Postorino Paolo , Curini Roberta , Bruno Maurizio
Published: August 2021

Tholu Bommalu are typical leather puppets of the traditional Indian shadow theatre. Two of these objects are part of a collection in the International Puppets Museum “Antonio Pasqualino” (Palermo, Sicily, Italy), which can count on one hundred-seventy-three of artifacts. These Indian puppets were investigated to obtain information related to the use of dyes for their manufacturing through a multi-technical approach exploiting the combination of highly sensitive spectroscopic techniques. Wet cotton stubbons were used to entrap small particles of dyes on the fibers from the art objects for the consequent analyses. Visible Light Micro-Reflectance spectroscopy was employed for the preliminary identification of the molecular class of dyes directly on the swabs, while Surface Enhanced Raman Scattering allowed the identification of the specific dye. Several synthetic dyes belonging to different typologies of coloring compounds were identified. The study resulted in an interesting overview of dyes used in recent Tholu Bommalata manufacturing through the combination of micro-invasive techniques directly on the sampling substrate.
The Changing Face of German Christmas Markets: Historic, Mercantile, Social, and Experiential Dimensions
Authors: Spennemann Dirk H.R. , Parker Murray
Published: August 2021

Annually, there are between 2500 and 3000 Christmas markets in Germany. While claiming to be rooted in century-old tradition, the current concept of the markets, shaped in the 1930s, gradually transformed from primarily mercantile operations to experiential events. In contemporary times, these markets also have quantifiable social and experiential dimensions. The last of these, the experiential dimension, is a mélange of visual, auditory, and olfactory components that create a compound sensory response—the “Christmas atmosphere”. There are copious intangible elements of these markets, which combined create a sum greater than the addition of each of the individual constituent components. We find the recognition of such collections of entwined intangible heritage is novel, warranting further research and documentation, as standard approaches to the identification and management of intangible cultural heritage are too limiting.
Evaluation of the Photocatalytic Activity of Water-Based TiO2 Nanoparticle Dispersions Applied on Historical Painting Surfaces
Authors: Pasquale Stefania , Zimbone Massimo , Ruffino Francesco , Stella Giuseppe , Gueli Anna Maria
Published: August 2021

This paper aims at assessing the use of nanomaterials in painting conservation and in cleaning practices that could be alternative to the traditional ones to overcome the limits of new green materials. Titanium dioxide nanoparticles have been spread and studied on historical painting surfaces with good results. In particular, the properties of TiO2 nanoparticles have been considered useful for self-cleaning and protective purposes against the accumulation of dirt and dust that represents the first phase in deterioration of historical painting surfaces. TiO2 nanoparticles, prepared in distilled water by Pulsed Laser Ablation in Liquids, were applied on painting mock-ups realized in the laboratory according to old recipes and using historical binders and pigments. The surface characteristics of the painting were investigated by contact angle measurement and by Atomic Force Microscopy. The optical and aesthetical compatibility of the colloidal dispersions with the painting was assessed by spectrophotometry, and then the cleaning efficiency was evaluated by discoloration of a dye under ultraviolet irradiation, at fixed time intervals, using colorimetric technique. Because of the high reactivity of nanoparticles, the possibility of degrading the painting surface, together with the chromatic marker, was examined by colorimetric measurements. The evaluation of the color changes is important for all the materials belonging to cultural heritage, especially painting, for which the color modification induced by protective and/or cleaning interventions could irremediably compromise the work of art.
Association of Family History and Life Habits in the Development of Colorectal Cancer: A Matched Case-Control Study in Mexico
Authors: Ramírez-Díaz María del Pilar , Alvarez-Bañuelos María T. , Robaina-Castellanos Martha S. , Castro-Enríquez Pedro P. , Guzmán-García Raúl E.
Published: August 2021

Colorectal cancer (CRC) is one of the most frequently diagnosed cancers and, as such, is important for public health. The increased incidence of this neoplasm is attributed to non-modifiable controls such as family history and modifiable variable behavioral risk factors involved in lifestyle like diets in Mexico. The presence of these factors is unknown. Therefore, the aim of this study was to evaluate family history and lifestyle factors associated with developing colorectal cancer in a Mexican population. Descriptive statistics and multivariate logistic regression were used to estimate the adjusted odds ratios (OR), as well as the 95% confidence intervals (CI). In this paper, significant differences were demonstrated between cases and controls. A family history of cancer (FHC) increased the probability of CRC [OR = 3.19 (95% CI: 1.81–5.60)]. The area of urban residence was found to be a protective factor compared to the rural area. This was also the case for frequent consumption of fruits [OR = 0.49 (95% CI: 0.28–0.88)], the frequent consumption of beef [OR = 2.95 (95% CI: 1.05–8.26)], pork [OR = 3.26 (95% CI: 1.34–7.90)], and region-typical fried food [OR = 2.79 (95% CI (1.32–5.89)]. These results provide additional evidence supporting the association of some CRC risk factors with family history of cancer, low fruit consumption, high consumption of red meat, and fried foods typical of the region of México. It is important to establish intervention methods, as well as genetic counseling to relatives of patients with CRC.
Stigma Mechanisms and Outcomes among Sub-Saharan African Descendants in Belgium—Contextualizing the HIV Stigma Framework
Authors: Manirankunda Lazare , Wallace Aletha , Ddungu Charles , Nöstlinger Christiana
Published: August 2021

HIV-related stigma and discrimination are recognized barriers to HIV prevention, testing and treatment among people of Sub-Saharan African descent (SSA) origin living in Belgium, but insights into HIV related-stigma mechanisms and outcomes are lacking for this population with high HIV prevalence. Guided by Earnshaw and Chaudoir’s stigma framework (2009), we conducted this qualitative study using 10 focus-groups with 76 SSA community members and 20 in-depth interviews with SSA descendants living with HIV to explore specific HIV-stigma mechanisms and outcomes and underlying drivers. Inductive and deductive thematic analysis showed high degrees of stigma among SSA communities driven by fear of HIV acquisition and misconceptions in a migration context, negatively affecting SSA descendants living with HIV. The results allowed for contextualization of the framework: At the community level, prejudices and stereotypes were major stigma mechanisms, while physical distancing, gossips, sexual rejection, violence and increased HIV prevalence emerged as stigma outcomes. Among SSA descendants living with HIV, enacted, anticipated and internalized stigmas were validated as stigma mechanisms, with witnessed stigma as an additional mechanism. Self-isolation, community avoidance and low utilization of non-HIV specialized healthcare were additional outcomes. These results are relevant for tailoring interventions to reduce HIV-related stigma.
Mobile Phone Use during Gait: The Role of Perceived Prioritization and Executive Control
Authors: Krasovsky Tal , Lanir Joel , Felberbaum Yasmin , Kizony Rachel
Published: August 2021

(1) Background: Mobile phone use during gait is associated with adverse health outcomes, namely increased risk of pedestrian injury. Healthy individuals can voluntarily prioritize concurrent task performance, but the factors underlying the impact of phone use during walking remain largely unknown. Thus, the objective of this work was to evaluate the relationship between subjective (perceived) prioritization, cognitive flexibility and dual-task performance when using a mobile phone during walking. (2) Methods: Thirty young participants walked for one minute with and without reading or texting on a mobile phone, as well as reading or texting while sitting. Walking performance (kinematics) was recorded, as well as phone use (text comprehension, text read/written), mental workload, perceived prioritization (visual analog scale), and cognitive flexibility (trail-making test). (3) Results: Texting while walking was associated with larger decreases in gait speed, larger gait variability, higher mental workload, and lower text comprehension compared to reading. Perceived prioritization was associated with walking dual-task costs (DTCs) (r = 0.39–0.42, p < 0.04) when texting, and better cognitive flexibility was associated with lower gait DTCs when texting (r = 0.55, p = 0.002) but not reading. (4) Conclusions: The context-dependent link between perceived prioritization, cognitive flexibility, and walking DTCs promotes our understanding of the factors underlying texting-while-walking performance. This could identify individuals who are more prone to dual-task interference in this increasingly common and dangerous task.
What Could Explain the Lower COVID-19 Burden in Africa despite Considerable Circulation of the SARS-CoV-2 Virus?
Authors: Wamai Richard G. , Hirsch Jason L. , Van Damme Wim , Alnwick David , Bailey Robert C. , Hodgins Stephen , Alam Uzma , Anyona Mamka
Published: August 2021

The differential spread and impact of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), causing Coronavirus Disease 2019 (COVID-19), across regions is a major focus for researchers and policy makers. Africa has attracted tremendous attention, due to predictions of catastrophic impacts that have not yet materialized. Early in the pandemic, the seemingly low African case count was largely attributed to low testing and case reporting. However, there is reason to consider that many African countries attenuated the spread and impacts early on. Factors explaining low spread include early government community-wide actions, population distribution, social contacts, and ecology of human habitation. While recent data from seroprevalence studies posit more extensive circulation of the virus, continuing low COVID-19 burden may be explained by the demographic pyramid, prevalence of pre-existing conditions, trained immunity, genetics, and broader sociocultural dynamics. Though all these prongs contribute to the observed profile of COVID-19 in Africa, some provide stronger evidence than others. This review is important to expand what is known about the differential impacts of pandemics, enhancing scientific understanding and gearing appropriate public health responses. Furthermore, it highlights potential lessons to draw from Africa for global health on assumptions regarding deadly viral pandemics, given its long experience with infectious diseases.
Effects of Financial Expenditure of Prefectures/Municipalities on Regional Suicide Mortality in Japan
Authors: Shiroyama Takashi , Fukuyama Kouji , Okada Motohiro
Published: August 2021

In Japan, suicide mortality has been improving from 2009; however, suicide remains one of the leading causes of death. Although previous studies identified solid relationships between governmental financial support for social welfare systems and suicide mortality, little attention is paid to how specific regional policies, designed according to regional cultural, economic, and social welfare situations, affect suicide mortality. Therefore, the present study analyses the relationships between the regional governmental expenditure of six major divisions and suicide mortality across the 47 prefectures in Japan from 2009 to 2018 using fixed-effect analysis of hierarchal linear regression with robust standard error. The expenditure in “public health”, “police”, “ambulance/fire services”, “welfare” and “education” is associated with reduction in suicide mortality, at least in some statistical indicators, whereas expenditure of “public works” indicated the influence of increasing suicide mortality or had no effect. Welfare expenditure was the most predominantly effective among the six major divisions of regional governmental expenditure. In the welfare subdivisions, expenditure of “child welfare” and “social welfare” was effective in a reduction in suicide mortality, but expenditure of “elderly welfare” surprisingly contributed to increasing suicide mortality. Child welfare expenditure negatively impacted suicide mortality in wide-ranging generations of both males and females; the positive effects of elderly welfare expenditure reached were limited as working-age populations increased, but unexpectedly did not affect the suicide mortality of elderly populations. The relatively increasing expenditure of elderly welfare with the relatively decreasing child welfare are unavoidable due to the Japanese social issues associated with a declining birth rate and ageing population. Furthermore, the budget of that regional government that can modify its expenditure structure by making its own policies is limited since most regional governmental expenditure is composed of essential expenditure for maintaining and operating regional social welfare systems. Although severe social situations in Japan are still unoptimised, the present results suggest that scientific-evidence-based redistributions of welfare expenditure in regional governments can at least partially improve Japanese society and welfare systems.
Factors Affecting Learning Satisfaction in Face-to-Face and Non-Face-to-Face Flipped Learning among Nursing Students
Authors: Cho Mi-Kyoung , Kim Mi Young
Published: August 2021

Factors influencing students’ learning satisfaction may differ between face-to-face and non-face-to-face flipped learning. For non-face-to-face flipped learning, which was widely employed during the COVID-19 pandemic, it is necessary to examine the impacts on learning satisfaction, which may vary depending on professor–student interaction rather than individual competencies, such as SDL readiness. This descriptive study, conducted 2 March 2019 to 24 June 2020, included 89 s-year, flipped-learning nursing students (28 face-to-face, 61 non-face-to-face). Students completed questionnaires about learning satisfaction, SDL readiness, and professor–student interaction. The data, collected using e-surveys, were analyzed using descriptive statistics, t-test, ANOVA, Pearson’s correlation, and multiple stepwise regression with IBM’s SPSS Statistics 25.0 program. The total average score of learning satisfaction (38.19 ± 6.04) was positively correlated with SDL readiness (r = 0.56, p < 0.001) and professor–student interaction (r = 0.36, p = 0.001), although total learning satisfaction was significantly different between the face-to-face and the non-face-to-face groups (t = 5.28, p = 0.024). They were also significant influencing factors, along with face-to-face flipped learning, for total learning satisfaction (F = 18.00, p < 0.001, explanatory power = 36.7%), suggesting flipped learners in non-face-to-face contexts must increase engagement beyond professor–student interaction.
Wind Environment Simulation Accuracy in Traditional Villages with Complex Layouts Based on CFD
Authors: Yao Xingbo , Han Shuo , Dewancker Bart
Published: August 2021

Using wind speed, wind direction, and turbulence intensity values as evaluation indicators, the ventilation performance of villages with complex building layouts was studied. We used the SKE, RNG, and RKE solvers in CFD-3D steady-state Reynolds-averaged Navier–Stokes (RANS) to simulate the wind environment of a village. The findings show that for the simulation of rural wind environments with complex building layouts, steady-state simulation solvers need to be evaluated in detail to verify their accuracy. In this study, a village with a complex architectural layout in Southern Shaanxi, China, was taken as the research object, and three steady-state simulation solvers were used to evaluate the ventilation performance of the village. The simulated data were compared with the measured data to find the most suitable solver for this kind of village wind environment simulation. The results show that for the simulation of the village wind environment with a complex building layout, the RNG simulation results have the lowest reliability among the three steady-state solvers. The reliability of wind speed distribution and turbulence intensity distribution are 0.7881 and 0.2473, respectively. However, the wind speed and turbulence intensity values obtained by the SKE solver are the closest to the measured values, which are 0.8625 and 0.9088, respectively. Therefore, for villages with complex building layouts, the SKE solver should be the first choice for simulating wind environment distribution. When using the RNG solver, the overall turbulence intensity value obtained is higher than the measured value. The average deviation between the simulated data and SKE and RKE at a height of 1.7 m is 42.61%. The main reason for this is that RNG overestimates the vortices and underestimates the airflow rate in the building intervals.
Quality of Life of Children and Adolescents with Multiple Sclerosis—A Literature Review of the Quantitative Evidence
Authors: Mrosková Slávka , Klímová Eleonóra , Majerníková Ľudmila , Tkáčová Ľubomíra
Published: August 2021

Background: Multiple sclerosis (MS) is a chronic disease of the central nervous system that also develops in patients under 18 years of age. The disease negatively affects the quality of life (QoL) of children and adolescents. We conducted a literature review. The aim of the review was to identify the QoL of pediatric patients with MS and assess the factors determining their QoL. Methods: We analyzed studies published between 2000 and 2020 in PubMed, Scopus, Science Direct, Web of Science, and EBSCO databases. Results: In all, 17 studies were included in the review. The most common tool in assessing QoL was the generic module PedsQL. The range of mean/median global score of QoL was 53.8–81.7. The worst QoL was dominantly reported in the school and emotional spheres, on the contrary, the disease’s least determined area of QoL was the social and physical dimension. In particular, disability and fatigue were important predictors of QoL. Conclusions: MS negatively affects the school and emotional spheres in particular, so it is important to pay greater attention to these spheres of life of MS patients. As the review studies pay insufficient attention to the analysis of positive factors and their impact on the QoL of MS patients, research should integrate these phenomena. The use of MS-targeted tools in future research in the pediatric MS population is also appropriate.
An Integrated Framework to Conceptualize and Develop the Vancouver Airways Health Literacy Tool (VAHLT)
Authors: Poureslami Iraj , Kopec Jacek , Tregobov Noah , Shum Jessica , Sawatzky Rick , Hohn Richard , FitzGerald J. Mark
Published: August 2021

There is currently no comprehensive tool to assess the functional health literacy (HL) skills of chronic airway disease (CAD) patients. The purpose of this article is to describe the development of a new HL measure, the Vancouver Airways Health Literacy Tool (VAHLT). The tool was developed through the following phases: (1) Tool conceptualization, consisting of: (A) a systematic review (SR), (B) focus group sessions with CAD patients to understand barriers and facilitators to CAD management, (C) a survey with key-informants to obtain strategies to mitigate self-management barriers and validate patient-derived topics, and (D) respiratory physicians’ review of the topics; (2) Scenario and item development; and (3) Tool testing and content validation. The SR identified the lack of a valid HL measurement tool for CAD patients. Patients provided an initial shortlist of disease-related self-care topics. Key-informants helped to finalize topics for inclusion. Respiratory physicians and patients contributed to the development of a scenario-based questionnaire, which was refined during three rounds of testing to develop a 44-item instrument comprising nine self-management passages. We highlight the holistic process of integrating information from the literature with knowledge gained from key stakeholders into our tool framework. Our approach to stakeholder engagement may be of interest to researchers developing similar tools, and could facilitate the development and testing of HL-based interventions to ultimately improve patient outcomes and reduce the burden on the healthcare system.
COVID-19-Related Financial Hardship, Job Loss, and Mental Health Symptoms: Findings from a Cross-Sectional Study in a Rural Agrarian Community in India
Authors: Chatterji Sangeeta , McDougal Lotus , Johns Nicole , Ghule Mohan , Rao Namratha , Raj Anita
Published: August 2021

Several countries, including India, imposed mandatory social distancing, quarantine, and lockdowns to stop the spread of the SARS-CoV-2 virus. Although these measures were effective in curbing the spread of the virus, prolonged social distancing, quarantine, and the resultant economic disruption led to an increase in financial stress and mental health concerns. Prior studies established a link between the first lockdown and an increase in mental health issues. However, few studies investigated the association between post-lockdown financial hardship, job loss, and mental health. In this study, we examined the association between COVID-19-related financial hardship, job loss, and mental health symptoms approximately nine months after the end of the first nationwide lockdown in India. Job loss was associated with higher reporting of mental health symptoms among men (aIRR = 1.16) while financial hardship was associated with poor mental health symptoms among women (aIRR = 1.29). Conversely, social support and government aid were associated with better mental health symptoms among women. Our findings highlight the need for financial assistance and job creation programs to aid families in the recovery process. There is also an urgent need for improving the availability and affordability of mental health services in rural areas.