bluuebunny/crossref_metadata_2025 huggingface dataset:
Cognitive Learning Assessment Based on FAHP and RSM: A Case Study of Introduction to Network course
Authors: Lin Chin-Tsai , Chang Shih-Jui , Chen Yung-Hui
Published: May 2021

With the progress and innovation of digital technology, people's knowledge acquisition, information exchange, and communication modes have changed significantly. The universality of emerging technology media enables instructional designers to use digital media to provide different teaching materials and teaching methods to meet the needs of individual learners according to their differences. Accordingly, this study takes the Introduction to Network course as an example, proposes a Fuzzy Analytic Hierarchy Process combined with Rule-Space Model to guide and analyze students' learning status, and imports Microsoft Technology Association international certification as empirical analysis. The study revealed that, the experts believe that “understanding protocols and services” is the most important part of the basic knowledge of the Internet, followed by “understanding network infrastructure” and “understanding network hardware.” In the section on learning performance, the average progress rates of two class were 69.44% and 62.20%, respectively, the students' scores were significantly improved. In the section on obtaining Microsoft Technology Association certification, the passing rates were 93.44% and 93.10%, which were significant improvements in certification passing rate. In the future, this study can be applied to other fields to improve the relative learning effect and make it broader and more diversified.
Interpersonal Theory of Suicide Using a Familismo Values Lens among Emerging Mexican Descent Adults
Authors: Aceves Daisy , Piña-Watson Brandy
Published: May 2021

The present study examined the Interpersonal Theory of Suicide (IPT) within a culturally relevant framework by simultaneously examining familismo values to explain suicidal ideation among Mexican descent emerging adults. With a sample of 249 Mexican descent emerging adults (age range: 18–25 years; M = 19.17; SD = 1.53; 65.5% women), the present study found that there was a significant interaction between perceived burdensomeness (PB) and familismo-subjugation of self values. These findings provide evidence that in the context of perceiving one’s self as being a burden on the family, having higher familismo subjugation of self-values puts one at higher risk for suicidal ideation than if they have lower subjugation values. These findings highlight that when dissonance occurs between one’s values and their lived experience, a higher risk of suicidal ideation occurs for Mexican descent emerging adults.
Combine effect of exposure to petrol, kerosene and diesel fumes: On hepatic oxidative stress and haematological function in rats
Authors: Owumi Solomon E , Oladimeji Bidemi N , Elebiyo Tobiloba C , Arunsi Uche O
Published: May 2021

Petroleum product fumes (PPFs) containing toxic organic components are pervasive in the environment, emanating from anthropogenic activities, including petroleum exploration and utilization by end-user activities from petrol–gasoline stations. Petrol station attendants are exposed to PPF through inhalation and dermal contact with consequent toxicological implications. We investigated the effects of chronic exposure (60 and 90 days) to petrol (P), kerosene (K) and diesel (D) alone and combined exposure to petrol, kerosene and diesel (PKD) fumes on hepatotoxicity, haematological function and oxidative stress in rats. Following sacrifice, we evaluated hepatic damage biomarkers, blood glucose, oxidative stress and haematological function. Chronic exposure to PPF significantly increased organo-somatic indices, blood glucose, biomarkers of hepatic toxicity and oxidative stress in an exposure duration-dependent manner. There was a simultaneous decrease in the protective capacity of antioxidants. Furthermore, exposure to PPF increased pro-inflammatory biomarkers in rats (90 > 60 days). Regardless of exposure duration, plateletcrit, mean platelet volume, platelet distribution width and red cell distribution width in the coefficient of variation increased, whereas red blood cell count, haemoglobin, packed cell volume, mean corpuscular volume, mean corpuscular haemoglobin, mean corpuscular haemoglobin concentration, white blood cell, lymphocyte, monocyte–basophil–eosinophil mixed counts and platelet count decreased after 60 and 90 days exposure. Microscopic examination of the liver demonstrated hepatic pathological changes paralleling the duration of exposure to PKD fumes. However, the injury observed was lesser to that of rats treated with the diethylnitrosamine – positive control. Our results expanded previous findings and further demonstrated the probable adverse effect on populations’ health occasioned by persistent exposure to PPF. Individuals chronically exposed by occupation to PPF may be at greater risk of developing disorders promoted by continuous oxido-inflammatory perturbation and suboptimal haematological–immunologic function – thereby enabling a permissive environment for pathogenesis notwithstanding the limitation of quantifying PPF absolute values in our model system.
Susceptibility-Weighted Magnetic Resonance Imaging (MRI) of Microbleeds in Pediatric Concussion
Authors: Virani Shane , Barton Alexander , Goodyear Bradley G. , Yeates Keith Owen , Brooks Brian L.
Published: May 2021

Objective:

The long-term consequences of pediatric concussion on brain structure are poorly understood. This study aimed to evaluate the presence and clinical significance of cerebral microbleeds several years after pediatric concussion.

Methods:

Children and adolescents 8-19 years of age with either a history of concussion (n = 35), or orthopedic injury (n = 20) participated. Mean time since injury for the sample was 30.4 months (SD = 19.6). Participants underwent susceptibility-weighted imaging, rated their depression and postconcussion symptoms, and completed cognitive testing. Parents of participants also completed symptom ratings for their child. Hypointensities in susceptibility-weighted images indicative of cerebral microbleeds were calculated as a measure of hypointensity burden.

Results:

Hypointensity burden did not differ significantly between participants with a history of concussion and those with a history of orthopedic injury. Depression ratings (self and parent report), postconcussion symptom ratings (self and parent report), and cognitive performance did not significantly correlate with hypointensity burden in the concussion group.

Conclusions:

These findings suggest that at approximately 2.5 years postinjury, children and adolescents with prior concussion do not have a greater amount of cerebral microbleeds compared to those with orthopedic injury. Future research should use longitudinal study designs and investigate children with persistent postconcussive symptoms to gain better insight into the long-term effects of concussion on cerebral microbleeds.
Standard Care Versus Awake Prone Position in Adult Nonintubated Patients With Acute Hypoxemic Respiratory Failure Secondary to COVID-19 Infection—A Multicenter Feasibility Randomized Controlled Trial
Authors: Jayakumar Devachandran , Ramachandran, DNB Pratheema , Rabindrarajan, DNB Ebenezer , Vijayaraghavan, MD Bharath Kumar Tirupakuzhi , Ramakrishnan, AB Nagarajan , Venkataraman, AB Ramesh
Published: May 2021

Rationale:

The feasibility and safety of awake prone positioning and its impact on outcomes in non-intubated patients with acute respiratory distress syndrome secondary to COVID-19 is unknown. Results of the observational studies published during this pandemic have been conflicting. In this context, we conducted a multi-center, parallel group, randomized controlled feasibility study on awake prone positioning in non-intubated patients with COVID-19 pneumonia requiring supplemental oxygen.

Methods:

60 patients with acute hypoxic respiratory failure secondary to COVID-19 pneumonia requiring 4 or more liters of oxygen to maintain a saturation of ≥92% were recruited in this study. Thirty patients each were randomized to either standard care or awake prone group. Patients randomized to the prone group were encouraged to self-prone for at least 6 hours a day. The primary outcome was the proportion of patients adhering to the protocol in each group.

Results:

In the prone group, 43% (13 out of 30) of patients were able to self-prone for 6 or more hours a day. In the supine group, 47% (14 out of 30) were completely supine and 53% spent some hours in the prone position, but none exceeded 6 hours. There was no significant difference in any of the secondary outcomes between the 2 groups and there were no adverse events.

Conclusions:

Awake prone positioning in non-intubated patients with acute hypoxic respiratory failure is feasible and safe under clinical trial conditions. The results of our feasibility study will potentially help in the design of larger definitive trials to address this key knowledge gap.
Social Work With Criminalized Women: Governance or Resistance in the Carceral State?
Authors: Leotti Sandra M.
Published: May 2021

Drawing on findings from a Foucauldian-inspired critical discourse analysis, this article examines the hegemonic ways in which social work engages with criminalized women. Utilizing the analytic of governmentality, I explore the construction of criminalized women in contemporary social work discourse and ask how those constructions support and shape practice with criminalized women. Results show that knowledge production in social work serves as a significant site through which the profession draws on, but also resists, carceral logics. I begin by discussing contemporary social work as a form of neoliberal governance. Specifically, I illuminate the ways in which social work is implicated in surveillance and control and how this involvement is obscured under the framework of helping. I then describe how bold counter discourses, such as those offered by abolitionist and anti-carceral thought foster spaces of resistance within the profession. I argue that social work should claim a stance of radical imagination in which we take seriously the calls to abolish the varying manifestations of the carceral state.
The Wheel of Change Moves On: Assessing the Severity of Stalking Behavior
Authors: Stefanska Ewa B. , Longpré Nicholas , Harriman Rekayla S.
Published: May 2021

Stalking is a significant social issue. The inconsistency as to what defines stalking has resulted in the creation of different methods to measure the crime. However, there has been minimal work done that assesses the severity of individual stalking behaviors. The aim of the present study was to assess the level of stalking behavior in terms of severity within a randomly selected sample of 924 cases from the database of the National Stalking Helpline. Item response theory analyses were used to assist in developing a scale that displays the ranking order of each stalking behavior. These analyses were also used to examine whether the stalking behavioral items created a single continuum of severity of stalking. Results indicated that 16 stalking behavioral items of the 28 items present in the National Stalking Helpline, best represented the severity of stalking. Unwanted communication behaviors such as text messages and phone calls were located at the lower end of the severity scale, whereas criminal damage and death threats were mapped on the higher end of the continuum. The findings also revealed that the 16 items categorized under 6 factors. The findings of the present study provide many implications for stalking agency professionals and criminal justice responses.
Adults’ Online and Offline Psychological Intimate Partner Violence Experiences
Authors: Schokkenbroek Janneke M. , Ouytsel Joris Van , Hardyns Wim , Ponnet Koen
Published: May 2021

Digital media offer ample possibilities for individuals to control and monitor their dating or romantic partner and to make hurtful comments. Although online psychological intimate partner violence has received increased research attention over the past few years, much remains unknown about its nature and its association with offline psychological intimate partner violence, especially among the adult population. Previous research remains inconclusive regarding the gendered nature of online intimate partner violence, and differences among various age groups have yet to be examined. The present study is intended to address these gaps in the literature by assessing the co-occurrence of psychological intimate partner violence victimization and perpetration, and the overlap between offline and online forms thereof. We conducted a large-scale survey study among a representative sample of 1,587 adults between the ages of 18 and 94 ( M = 48.1, SD = 18.6), of which 1,144 ( Mage = 47.7 years, 51.3% female) were in relationships at the time of data collection (2019). Our study findings indicate that experiences of online and offline psychological intimate partner violence tend to co-occur, as do victimization and perpetration experiences. Furthermore, we found that men were more often victims of both online and offline psychological partner violence than women, and women were more often perpetrators of both forms of psychological intimate partner violence than men. Younger age groups reported more victimization and perpetration of online and offline psychological intimate partner violence than older respondents. The results of our study underscore the need for age-appropriate intimate partner violence prevention.
Mask Up: Exploring Cross-Cultural Influences on Mask-Making Behavior During the COVID-19 Pandemic
Authors: Hahn Kim H. Y. , Bhaduri Gargi
Published: May 2021

At the beginning of the COVID-19 pandemic, people from around the world made numerous homemade masks for themselves and their community due to shortage of medical masks as well as to stop the spread of COVID-19. The purpose of the current study was to conduct cross cultural exploration of the reasons for making masks, self-construal and wellbeing associated with masks making by collecting data from residents across US, India, and China. The finding of this study presented different reasons for making masks as well as self-construal, and wellbeing in people who made masks versus those who did not. Differences were also observed among three different cultural groups. This study offers a unique contribution to the public health research engaging in craft making related activities to gain a better perspective of the state of health of a population and the understanding of cross-cultural study of craft making behavior during the pandemic.
Different Meanings of Proper Nutrition: The Sociopolitical Dynamics of the Relationship between Body and State in the 1970s and 2010s Poland
Authors: Straczuk Justyna
Published: May 2021

In this article, we comparatively analyze expert discourses and lay attitudes to healthy eating in socialist and contemporary Poland. The investigation makes apparent significant changes that have occurred in between these two periods. From legitimate and peremptory knowledge with an unchangeable and universal character, dietary guidance evolved into being much less authoritative in nature, facilitating various alternative ways of thinking and debate. The recipients of nutritional advice have also changed: from subordinated citizens and only passive objects of experts’ actions to the self-governing neoliberal subjects, which are active agents of their own choices and are individually responsible for their well-being. During socialist times, proper eating, in line with dietitian’s recommendations, was of secondary importance as Polish citizens were primarily motivated by the need to procure food of adequate quality and in sufficient quantity. Nowadays, under free-market economics and changing lifestyles, eating healthily is an issue of fundamental concern for many people. This analysis reveals that the production of nutritional knowledge is tightly related to sociopolitical contexts and that changing food attitudes are both influenced by post-socialist transformations as well as broader sociocultural processes.
The Impact of Theory in HPV Vaccination Promotion Research: A Systematic Review and Meta-Analysis
Authors: Xiao Xizhu , Lee Danielle Ka Lai , Wong Rachel Min , Borah Porismita
Published: May 2021

Objective:

Numerous studies examined HPV vaccination promotional strategies. However, an overview of theory use, a synthesis of strategies’ effectiveness and an examination of the moderating influence of theory are absent.

Data Source:

We retrieved studies from Academic Search Complete, Business Source Complete, PubMed, PsycINFO, Web of Science, CMMC, CINAHL, and MEDLINE.

Study Inclusion and Exclusion Criteria:

1) peer-reviewed articles written in English, 2) experimental or quasi-experimental, 3) measure HPV vaccination-related outcomes, 4) had to contain a control condition and report statistics necessary for conversion (for meta-analysis only).

Data Extraction:

70 and 30 studies were included for the systematic review and meta-analysis respectively.

Data Synthesis:

Four major categories were coded: study information, theory use, type of theory, and outcomes. Two independent coders coded the sample (Cohen’s Kappa ranged from .8 to 1).

Results:

Most of the studies were based in the U.S. (77%, k = 54) with convenient samples (80%, k = 56), targeted toward females (46%, k = 32), and around a quarter did not employ any theories (47%, k = 33). Among theory-driven studies, the most commonly used were Framing (22%, k = 19), Health Belief Model (HBM; 13%, k = 12), and Narrative (7%, k = 6). Among controlled studies, promotional strategies were significantly more effective compared to the control (r+ = .25, p < .001). Strategies guided by the information, motivation, behavioral skills model (IMB) were more effective (r+ = .75, p < .001) than studies guided by framing theory (r+ = −.23, p < .001), HBM (r+ = .01, p < .001), and other theories (r+ = .11, p < .001).

Conclusion:

This review contributes to HPV vaccination promotion literature by offering a comprehensive overview of promotional strategies and practical suggestions for future research and practices.
Theoretical Mediators of Diabetes Risk and Quality of Life Following a Diabetes Prevention Program for Latino Youth With Obesity
Authors: Soltero Erica G. , Ayers Stephanie L. , Avalos Marvyn A. , Peña Armando , Williams Allison N. , Olson Micah L. , Konopken Yolanda P. , Castro Felipe G. , Arcoleo Kimberly J. , Keller Colleen S. , Patrick Donald L. , Jager Justin , Shaibi Gabriel Q.
Published: May 2021

Purpose:

This study tested self-efficacy and social support for activity and dietary changes as mediators of changes in type 2 diabetes related outcomes following a lifestyle intervention among Latino youth.

Setting and Intervention:

Latino adolescents (14-16 years) with obesity (BMI% = 98.1 ± 1.4) were randomized to a 3-month intervention (n = 67) that fostered self-efficacy and social support through weekly, family-centered sessions or a comparison condition (n = 69).

Measures:

Primary outcomes included insulin sensitivity and weight specific quality of life. Mediators included self-efficacy, friend, and family social support for health behaviors. Data was collected at baseline, 3-months, 6-months, and 12-months.

Analysis:

Sequential path analysis was used to examine mediators as mechanisms by which the intervention influenced primary outcomes.

Results:

The intervention had a direct effect on family (β = 0.33, P < .01) and friend social support (β = 0.22, P < .001) immediately following the intervention (3-months). Increased family social support mediated the intervention’s effect on self-efficacy at 6-months (β = 0.09, P < .01). However, social support and self-efficacy did not mediate long-term changes in primary outcomes ( P > .05) at 12-months.

Conclusions:

Family social support may improve self-efficacy for health behaviors in high-risk Latino youth, highlighting the important role of family diabetes prevention. Fostering family social support is a critical intervention target and more research is needed to understand family-level factors that have the potential to lead to long-term metabolic and psychosocial outcome in vulnerable youth.
Individual and experiential predictors of character development across the deployment cycle
Authors: Chopik William J , Kelley Whitney L , Vie Loryana L , Lester Paul B , Bonett Douglas G , Lucas Richard E , Seligman Martin EP
Published: May 2021

How soldiers adapt to and change in response to the deployment experience has received a great deal of attention. What predicts which soldiers are resilient and which soldiers decline in character strengths across the deployment transition? We examined this question in two analyses drawing from the same data source of soldiers deploying for the first time (Analysis 1: N = 179,026; Analysis 2: N = 85,285; Mage = 24.6–24.7 years old, SD = 4.87; 66.5–66.9% White). Specifically, we examined how individual (e.g. sociodemographic, military) and deployment (e.g. stressful experiences) characteristics predict character development across the deployment cycle. Character strengths were assessed once before and up to three times after soldiers’ return from deployment. Reproducing previous work, we found evidence for two classes of change—a resilient class (“stable high”) and a recovery class (“persistent low”). The strongest predictor of high, resilient character strength levels was better self-rated health at baseline. The findings are discussed in the context of the mechanisms that drive character development, evidence for post-traumatic growth, and practical implications for the U.S. Army.
Nonreligious Employees’ Perceptions of Microaggressions and Their Relationship With Job Satisfaction as Moderated by Calling
Authors: Schultz Jessica N. , Leuty Melanie E. , Bullock-Yowell Emily , Mohn Richard
Published: May 2021

Workplace microaggressions are related to person–organization fit (P-O fit) and job satisfaction. Additionally, P-O fit and calling predict job satisfaction. Given the religious connotations of calling, research has excluded study of these relationships in nonreligious samples, a growing segment of the U.S. population. To address this, it was predicted that P-O fit would mediate the relationship between microaggressions and job satisfaction, and calling would moderate the relationship between microaggressions and P-O fit. In a sample of 296 nonreligious employed adults, microaggressions predicted job satisfaction, while calling predicted P-O fit and job satisfaction; however, P-O fit did not mediate these relationships, and calling did not moderate microaggressions and P-O fit. Post hoc analyses revealed that calling moderated microaggressions and job satisfaction. Implications for research and vocational guidance with nonreligious individuals are discussed.
The Impact of Anticoagulation on COVID-19 (SARS CoV-2) Patient Outcomes: A Systematic Review
Authors: Lazaridis Dovena , Leung Simon , Kohler Lisa , Smith Carla Hawkins , Kearson Margaretta L. , Eraikhuemen Nathaniel
Published: May 2021

Background:

Emerging data suggest that coagulopathy, cytokine storm, and acute respiratory distress syndrome are associated with the 2019 coronavirus disease (COVID-19). The prevalence of hypercoagulable state in these patients is unknown, but appears to be higher compared to those with other critically ill patients. Elevated D-dimer, large blood vessels clots, deep vein thrombosis, pulmonary embolism and disseminated intravascular coagulation have been reported in patients diagnosed with COVID-19 either on admission or during hospitalization and may be predictors of poor outcomes.

Methods:

We performed a comprehensive literature review using the search terms of COVID-19; severe acute respiratory syndrome coronavirus-2, coagulopathy, thrombosis and anticoagulation in PubMed, Ovid, google scholar, Medline and EMBASE databases from December 2019 to May 30, 2020.

Results:

A total of 64 relevant studies were reviewed; of which, 4 studies met the inclusion criteria and were included for analysis. The majority of the studies were retrospective involving 525 critically ill COVID-19 patients. The most commonly studied anticoagulant administered was low molecular weight heparins. Anticoagulation dosing varied throughout the studies and may be classified as standard venous thromboembolism prophylaxis, intermediate dosing, or full dose anticoagulation. The most studied objective was improvement in coagulopathy. Significant reduction in D-dimer, improvement in coagulopathy markers such as Interlukin-6, fibrinogen degradation product level, as well as lymphocyte count were reported.

Conclusion:

Despite the limited quality of studies analyzed, prophylaxis and higher intensity dosed anticoagulation is associated with improved pulmonary oxygenation, decreased coagulopathy markers and decreased mortality in COVID-19 patients.
Dependency Change with Aging and Associated Factors in Uruguay: A Cohort Study
Authors: Marroig Alejandra , Machado Maximiliano , Muniz-Terrera Graciela
Published: May 2021

Objectives: To assess the heterogeneity of transitions toward dependency in older adults and to explore the robustness of results to different operationalizations of dependency. Method: Using data from people aged 60 years and older from a national representative study in Uruguay ( Encuesta Longitudinal de Protección Social, N = 5071), we fitted multinomial regressions adjusted by sociodemographic and health characteristics to model transitions into dependency and death. We used a harder operationalization with basic activities of daily living (Katz-dependency) and Comprehensive-dependency with basic, instrumental, and advanced activities. Results: Increasing age (RRR = 1.08, CI = [1.05; 1.12], p < .001) and having comorbidities (RRR = 2.16, CI = [1.31; 3.57], p = .003) increased the risk of transition from nondependent to dependent using Katz-dependency. Women with at least two chronic conditions have increased risk of Comprehensive-dependency (RRR = 1.79, CI = [1.15; 2.80], p = .010). Discussion: Inconsistencies in findings emerged when evaluating transitions into dependency with the different measures, which may have social care implications.
The tragedy of the private: Theft, property, and the loss of a commons
Authors: Philipsen Dirk
Published: May 2021

In a world of escalating climate crisis, metastasizing market logic, structural racism, growing inequality, and a global pandemic, this essay argues, the tragedy is not one of the commons, but one of the private. The relentless capitalist focus on self-interest rather than common good, on efficiency rather than resilience, on more rather than better, on the private over the public, has brought societies and ecosystems alike to the breaking point. As COVID-19 has helped us rediscover, wellbeing instead depends on a healthy commons—resilience, reciprocity, solidarity, and sharing. The essay ends with practical suggestions as to how to move in the direction of an economy squarely focused on wellbeing of people and planet.
Life versus Capital: The COVID-19 pandemic and the politics of life
Authors: De Genova Nicholas
Published: May 2021

Like all ostensibly “natural” disasters, the COVID-19 coronavirus pandemic unceasingly reveals the depths of social inequality and political myopia or governmental recklessness that predictably exacerbate the effects of a more strictly natural calamity. The pandemic thereby exposes the grotesque disparities in how illness, death, and suffering are unevenly distributed. As the COVID-19 public health crisis has summarily provoked a global economic crisis, furthermore, it is simply unthinkable to comprehend the real ramifications of the pandemic outside of the sociopolitical relations of labor and capital, more generally. Furthermore, the global public health crisis commands that we reflect anew on the relations between human life and state power. Both for those who have historically and enduringly been subjected to expulsion from gainful employment, as for those whose labor-power is a commodity of choice for capital, exceedingly selected for hyper-exploitation, the coronavirus pandemic is a toxic matter of both class and race. These dire and increasingly desperate circumstances, however, reveal not only what is most barbaric about capitalist social relations but also the opportunity latent within this crisis.
Killing Them ‘Softly’ (!): Exploring Work Experiences in Care-Based Animal Dirty Work
Authors: Tallberg Linda , Jordan Peter J
Published: May 2021

Working with animals is a daily occurrence for millions of people who often complete tasks which are tainted, in spite of the work being seen as essential in modern society. Animal shelter-work is such an occupation. This article contributes to a deeper understanding of the caring–killing paradox (a dissonance that workers face when killing animals they are also caring for), through an insider ethnographic study. We find that care-based animal dirty work consists of unique ambiguities and tensions related to powerlessness, deception and secrecy in the work based on a ‘processing-plant’ framework which informs how workers deal with unwanted animals. We find competing ideologies of care and control to be foundational in this work.
Superfluous Jobs in Extractive Industries: The Usefulness/Uselessness of Job Creation after Dispossession
Authors: Geenen Sara , Gleiberman Mollie
Published: May 2021

Job creation has become central to the global development agenda. Extractive industries in particular highlight employment opportunities for the host communities in which they operate through direct, indirect and induced jobs. Exploring literature on surplus populations/dispossession and distributive politics/Corporate Social Responsibility and using evidence from the Democratic Republic of Congo, we scrutinize the idea of job creation in the extractive industries as a development strategy. We argue that (1) superfluous jobs are being created to keep people alive yet silent in the wake of dispossession; and that (2) while they may help certain people to ‘stay alive’, these jobs also produce new inequalities and further marginalization.
‘Working While Feeling Awful Is Normal’: One Roma’s Experience of Presenteeism
Authors: Collins Helen , Barry Susan , Dzuga Piotr
Published: May 2021

This article presents an account of a young Roma man’s lived experience of working in the agricultural sector while sick, and shines a spotlight on the impact of precarious work, low pay and eligibility, and access to sick pay, with particular emphasis on Roma, and how these factors interconnect to foster presenteeism. The repercussions of presenteeism, relayed through Piotr’s personal narrative and reflections about his work, family role, ambition and daily survival, enrich public sociology about this under explored area of migrant Roma’s working life.
Bibliometrix analysis of medical tourism
Authors: Campra Maura , Riva Patrizia , Oricchio Gianluca , Brescia Valerio
Published: May 2021

Medical tourism is an expanding phenomenon. Scientific studies address the changes and challenges of the present and future trend. However, no research considers the study of bibliometric variables and area of business, management and accounting. This bibliometric analysis discovered the following elements: (1) The main articles are based on guest services, management, leadership principles applied, hotel services associated with healthcare, marketing variables and elements that guide the choice in medical tourism; (2) The main authors do not deal with tourism but are involved in various ways in the national health system of the countries of origin or in WHO; (3)cost-efficiency and analytical accounting linked to medical tourism structures and destination choices are not yet developed topics.
Preparation and non-isothermal cure kinetics study of epoxy resin nanocomposites with amine and epoxy functionalized magnetic nanoparticles
Authors: Shahrestanaki Ali Akbar Keivanloo , Mehrshad Mohammad , Akhlaghi Seyed Hashem
Published: May 2021

Amine-functionalized magnetic nanoparticles NiFe2O4@SiO2@Amine (AMNP), and epoxy functionalized magnetic nanoparticles, CuFe2O4@SiO2@Epoxy (EMNP) were synthesized in three steps. Homogeneous stable dispersion of AMNP and EMNP, at concentrations of 1, 5, 10, 15, 20 wt% in epoxy resin were prepared using stoichiometric amounts of 4,4’-diaminodiphenylsulfone (DDS) as a curing. The optimum ratio of AMNP and EMNP were found to be 5%, and these were investigated by the total enthalpy of the curing reaction using differential scanning calorimetry (DSC) thermograms at 10°C/min. The cure kinetics of epoxy resin-functional magnetic nanoparticles-DDS composites were studied using non-isothermal DSC thermograms at different heating rates (5, 10, 15, 20°C/min). The kinetic parameters of the curing process, such as activation energy ( Ea), pre-exponential factor ( A), and rate constant ( k) were determined using several non-isothermal kinetic methods: Kissinger-Akahira-Sunose (KAS), Kissinger, Straink, Flynn-Wall-Ozawa (OFW), and Bosewell. The kinetic curing values obtained with different kinetic methods are well-matched. The Ea values were calculated in the range of 59.80 to 65.94, 57.69 to 63.92, and 45.38 to 52.45 kJ.mol−1 for the DGEBA/DDS, DGEBA/DDS/AMNP, and DGEBA/DDS/EMNP systems respectively. Also, The A values, using the Kissinger method, were calculated to be in the range of 7.0 × 105, 4.0 × 105, and 0.2 × 105 S−1 for the DGEBA/DDS, DGEBA/DDS/AMNP, and DGEBA/DDS/EMNP systems respectively. The glass transition temperatures of cured resins were determined with DSC, and the surface morphology of the nanocomposites and also the dispersion of the nanoparticles were investigated using scanning electron microscopy (SEM).
Optimization of friction stir back extrusion mechanical properties and productivity of magnesium AZ31-B seamless tubes
Authors: Alhourani Abdulla , Awad Mahmoud , Nazzal Mohammad A , Darras Basil M
Published: May 2021

Friction Stir Back Extrusion (FSBE) is a new sustainable manufacturing process capable of producing fine grained lightweight tubular shapes. The objective of this work is to investigate the impact of rotational speed and feed rate on the mechanical properties, cycle time and power consumption of friction stir back extruded Mg AZ31-B tubes and determine the optimal settings. FSBE experiments and tensile tests were performed to characterize the mechanical properties of the produced tubes. The investigation is conducted utilizing Response Surface Methodology (RSM) and desirability multi-response optimization technique. Results suggest that ultimate tensile strength and toughness are impacted by both rotational speed and feed rate and are more sensitive to speed. However, both process parameters did not show a significant statistical impact on elongation. Optimal parameters for mechanical properties were identified at a rotational speed of 1767 rpm and feed rate of 102 mm/min. The optimal settings to maximize mechanical properties, minimize power consumption, and maximize productivity were 2000 rpm and 116 mm/min.
Multi-objective adaptive cruise controller design using nonlinear predictive controller with the objective function with variable weights determined by fuzzy logic controller
Authors: Samani Behzad , Shamekhi Amir H.
Published: May 2021

In this paper, an adaptive cruise control system with a hierarchical control structure is designed. The upper-level controller is a model predictive controller (MPC) that by minimizing an objective function in the presence of the constraints, calculates the desired acceleration as control input and sends it to the lower-level controller. So the lower-level controller, which is a fuzzy controller, determines the amount of throttle valve opening or brake pressure to get the car to this desired acceleration. The model predictive controller performs optimization at each control step to minimize the objective function and achieve the reference values. Usually, the objective function has predetermined and constant weights to meet objectives such as maintain the driver’s desired speed and increase safety and in some cases increase comfort and reduce fuel consumption. In this paper, it is suggested that instead of using constant weights in the objective function, these weights should be determined by a fuzzy controller, depending on the different conditions in which the car is placed. The simulation results show that the variability of the weights of the objective function achieves control objectives much better than the optimization of the objective function with constant weights.
Hysteresis loss of ultra-large off-the-road tire rubber compounds based on operating conditions at mine sites
Authors: Ma Shaosen , Huang Guangping , Obaia Khaled , Moon Soon Won , Liu Wei Victor
Published: May 2021

The objective of this study is to investigate the hysteresis loss of ultra-large off-the-road (OTR) tire rubber compounds based on typical operating conditions at mine sites. Cyclic tensile tests were conducted on tread and sidewall compounds at six strain levels ranging from 10% to 100%, eight strain rates from 10% to 500% s−1 and 14 rubber temperatures from −30°C to 100°C. The test results showed that a large strain level (e.g. 100%) increased the hysteresis loss of tire rubber compounds considerably. Hysteresis loss of tire rubber compounds increased with a rise of strain rates, and the increasing rates became greater at large strain levels (e.g. 100%). Moreover, a rise of rubber temperatures caused a decrease in hysteresis loss; however, the decrease became less significant when the rubber temperatures were above 10°C. Compared with tread compounds, sidewall compounds showed greater hysteresis loss values and more rapid increases in hysteresis loss with the rising strain rate.
A method for tire wet grip performance evaluation based on grounding characteristics
Authors: Liang Chen , Shan Maoqing , Wang Guolin , Zhu Daqian , Chen Xingpeng
Published: May 2021

The wet grip performance of tire is one of the important performances affecting vehicle safety. The steering, acceleration, and braking of the vehicle are directly affected by the grounding characteristics between the radial tire and the ground. In order to study the influence of grounding characteristics of the tire on wet grip performance, ten 205/55R16 tires produced by different manufacturers were selected and tested. The grounding characteristics of the tires were tested using an optical test rig for tire grounding pressure distribution, considering inflation pressure distribution, load and wheel alignment. The tire-road contact area was subdivided into five parts, and 69 parameters were used to describe the grounding characteristics. A software was proposed to process the test results automatically, and 69 grounding characteristic parameters of each tire were obtained. Correlation analysis on tire wet grip performance and grounding characteristics was used for selecting the principal parameters. Finally, eight grounding characteristic parameters related to tire wet grip performance was obtained. Among them are five grounding characteristic parameters (central area rectangle ratio, central area width, internal shoulder length-to-width ratio, external and internal shoulder contact area ratio, external and internal shoulder impression area ratio) which have high correlation to tire wet grip performance, and three grounding characteristic parameters (external shoulder width, external shoulder length-to-width ratio, external and internal shoulder width ratio) which have low correlation to the wet grip performance of the tire. The principal component analysis method was used to analyze the highly correlated grounding characteristic parameters, and the regression equation for evaluating tire wet grip performance was fitted. The comparison of experimental and fitted values show that the errors are within 4%. The result demonstrates that, the method for evaluating wet grip performance of the radial tire through tire-road grounding characteristics was achieved.
Characterization of dissimilar liquids mixing in T-junction and offset T-junction microchannels
Authors: Ringkai H , Tamrin KF , Sheikh NA , Barroy P
Published: May 2021

Micromixing process in microfluidic devices has been broadly employed in bio-, nano-, and environmental technologies using either miscible or immiscible liquids. However, there are limited experimental studies investigating the mixing process of different densities and viscosities liquids in relation to microfluidics. Therefore, the mixing process of propan-2-ol and water, water and sodium chloride solution, propan-2-ol and sodium chloride solution were experimented and reported at 5 ≤ Re ≤ 50 in T-junction and offset T-junction microchannels. For miscible mixing experiments, i.e. propan-2-ol and water, water and sodium chloride solution, both microchannels show mixing index for each Reynolds number is directly proportional to the mixing time. At low Reynolds number, higher molecular diffusion takes place while at low flow rate, the residence time of fluid is high. The mixing performance is relatively good at high Reynolds number of 40 and 50 due to the significant convection which is caused by the effect of stretching and thinning of liquid lamellae. For immiscible propan-2-ol and sodium chloride solution mixing, offset T-junction microchannel offers better mixing performance than T-junction microchannel at both low and high Reynolds number. The chaotic mixing happened at the intersection of the T-junction microchannel due to the direct interaction of two liquids entering the junction at high momentum.
Effect of heater and condenser orientations on fluid flow behaviour in a two-phase natural circulation loop
Authors: Sudheer S Venkata Sai , Kumar K Kiran , Balasubramanian Karthik
Published: May 2021

A Numerical investigation on the influence of heater and condenser orientation and its location on steady state performance of a Two Phase Natural Circulation Loop (TPNCL) is presented. In the present study, four possible orientations are considered in TPNCL namely, Vertical Heater and Vertical Condenser (VHVC), Vertical Heater and Horizontal Condenser (VHHC), Horizontal Heater and Horizontal Condenser (HHHC) and Horizontal Heater and Vertical Condenser (HHVC). An in house MATLAB code is developed to solve the systems of equations. Homogeneous equilibrium model (HEM) is used in two phase regions. It is observed that steady state mass flow rate of the loop is significantly influenced by the developed pressure gradient in the riser and downcomer sections, as well as available vapour quality in the riser section. Moreover, it is also noticed that condenser position and orientation significantly effects the thermo-hydraulic characteristic of loop compared with heater orientation.
Parameter study and optimization design of a hat oblique tunnel portal
Authors: Guo Zijian , Liu Tanghong , Li Wenhui , Xia Yutao
Published: May 2021

The present work focuses on the aerodynamic problems resulting from a high-speed train (HST) passing through a tunnel. Numerical simulations were employed to obtain the numerical results, and they were verified by a moving-model test. Two responses, [Formula: see text] (coefficient of the peak-to-peak pressure of a single fluctuation) and[Formula: see text] (pressure value of micro-pressure wave), were studied with regard to the three building parameters of the portal-hat buffer structure of the tunnel entrance and exit. The MOPSO (multi-objective particle swarm optimization) method was employed to solve the optimization problem in order to find the minimum [Formula: see text] and[Formula: see text]. Results showed that the effects of the three design parameters on [Formula: see text] were not monotonous, and the influences of[Formula: see text] (the oblique angle of the portal) and [Formula: see text] (the height of the hat structure) were more significant than that of[Formula: see text] (the angle between the vertical line of the portal and the hat). Monotonically decreasing responses were found in [Formula: see text] for [Formula: see text] and[Formula: see text]. The Pareto front of [Formula: see text] and[Formula: see text]was obtained. The ideal single-objective optimums for each response located at the ends of the Pareto front had values of 1.0560 for [Formula: see text] and 101.8 Pa for[Formula: see text].
Novel Gaussian mixture model based nonsingular terminal sliding mode control for spacecraft close-range proximity with complex shape obstacle
Authors: Wang Yi , Yao Wen , Chen Xiaoqian , Ceriotti Matteo , Bai Yuzhu , Zhu Xiaozhou
Published: May 2021

This study is mainly focusing on the problem of spacecraft close-range proximity with obstacle avoidance in the presence of complex shape. A novel Gaussian mixture model–based nonsingular terminal sliding mode control (GMM-NTSMC) is proposed. This is achieved by developing GMM-based potential function with a switching surface of NTSMC. It is theoretically proved that the closed-loop system is globally stable. The main contribution of this study is that the GMM-based avoiding strategies, which include the GMM-based terminal sliding mode control (GMM-TSMC) and GMM-NTSMC, can solve the collision avoidance problem considering complex shape while the artificial potential function–based terminal sliding model control (APF-TSMC) fails. Moreover, the GMM-NTSMC and the GMM-TSMC require less energy with respect to the APF-TSMC. Furthermore, the GMM-NTSMC retains the advantage of the NTSMC and can avoid singularity problem while GMM-TSMC cannot. Finally, numerical simulations are performed to verify the effectiveness and superiority of the proposed GMM-NTSMC.
Effects of spin rate on the surface pressure distribution of a rotating model
Authors: Askary Farshid , Soltani Mohammad Reza
Published: May 2021

A new experimental technique has been developed to measure the pressure distribution over the surface of a rotating model in a wind tunnel for various spin rates, free-stream Mach numbers, and angles of attack. In this method, all of the measuring instruments are placed inside the rotating model which eliminated previous operational limitations and technical problems associated with attempts to measure the Magnus effect. The validity and reliability of the measured data was verified by comparing the integrated surface pressure values and aerodynamic forces, with those directly measured from an internal strain gauge balance. From the acquired surface pressure data distribution of both local and total Magnus force on the model as well as the interpretation of the boundary layer and flow separation effects on the rotating model could be determined. The Magnus force distribution shows that the local Magnus force increases along the length of the model and the maximum local Magnus force occurs at the end of the projectile. The acquired experimental data were further compared with the numerical simulations and satisfactory results were achieved. This new experimental technique can be easily applied to a variety of model configurations testing at different Mach numbers, spin rates, angles of attack, etc.