bluuebunny/crossref_metadata_2025 huggingface dataset:
Achieving Triple Aim Outcomes: An Evaluation of the Texas Medicaid Waiver
Authors: Revere Lee , Kavarthapu Nina , Hall Jessica , Begley Charles
Published: June 2020

The Texas Medicaid Waiver, via the Delivery System Reform Incentive Payment (DSRIP) program, has provided a path for Texas to achieve the Triple Aim through its focus on a defined population at the project and system levels, and financial payment policy based on outcomes. Both iterations of the DSRIP program (Waiver 1.0 and 2.0) have helped define populations, created regional collaboration that sets the stage for a true integrator, and provided financial incentives for improving population health, enhancing patient experience, and controlling costs. The flexible design of project menus and measure bundles in DSRIP encouraged a variety of projects, numerous measures of success and (often) overlapping populations of individual served to achieve the ultimate goal of the Triple Aim. This research outlines the major features of Texas DSRIP and demonstrates the Medicaid Waiver effectively contributed to measurable improvements in health, suggesting Texas safety net providers are moving closer to Triple Aim achievement.
The Structure of Academic Achievement: Searching for Proximal Mechanisms Using Causal Discovery Algorithms
Authors: Quintana Rafael
Published: June 2020

Causal search algorithms have been effectively applied in different fields including biology, genetics, climate science, medicine, and neuroscience. However, there have been scant applications of these methods in social and behavioral sciences. This article provides an illustrative example of how causal search algorithms can shed light on important social and behavioral problems by using these algorithms to find the proximal mechanisms of academic achievement. Using a nationally representative data set with a wide range of relevant contextual and psychological factors, I implement four causal search procedures that varied important dimensions in the algorithms. Consistent with previous research, the algorithms identified prior achievement, executive functions (in particular, working memory, cognitive flexibility, and attentional focusing), and motivation as direct causes of academic achievement. I discuss the advantages and limitations of graphical models in general and causal search algorithms in particular for understanding social and behavioral problems.
Association of arsenic with recurrence of urinary bladder cancer
Authors: Pal Dilip K , Agrawal Akash , Ghosh Sabnam , Ghosh Amlan
Published: June 2020

Arsenic is known to be an important aetiological factor for the development of urinary bladder cancer. It is known to be found excessively in ground water in certain geographical areas, including West Bengal. We have studied patients with recurrent bladder cancer from different areas of this Indian state and correlated arsenic as a causative aetiological factor for development and aggressiveness of the biological behaviour of urinary cancer. We included 31 patients from various parts of West Bengal state with recurrent bladder cancer who were operated in our institute. Their clinical and residential data and their arsenic content of tumour tissue were measured. Statistical analysis was performed to test the association of tissue arsenic with clinicopathological features of recurrent disease. We found very high levels of arsenic in tumour tissue in all residents of the districts with high prevalence of arsenic in the drinking water. We also observed more aggressive clinicopathological progression and early recurrence in patients with high arsenic content. We conclude that arsenic is a causal factor in the clinicopathological progression of recurrent urinary bladder cancer. Measures to decrease the level of arsenic in drinking water should be taken as this may both improve clinicopathological outcomes in the recurrence of urinary bladder carcinoma, as well as reducing its overall incidence.
Sustaining transnational activism between Indonesia and Hong Kong
Authors: Amalia Ezka
Published: June 2020

This article explores the relationship between Migrant CARE, a migrant labor NGO in Indonesia, and the Indonesian Migrant Workers Union in Hong Kong and their potential to advocate for better protection of migrant workers’ rights by the Indonesian government. Indonesia’s transition into democracy, Hong Kong’s promotion of civil rights and the United Nations International Convention on the Protection of the Rights of All Migrant Workers and Their Families provide opportunities for advocacy activism for Indonesian migrant workers and the possibility of cross-border cooperation of organizations in these two places. Previous studies show cross-border linkages of activism between Indonesia and Hong Kong but they do not pay attention to the factors that could promote sustaining the network. This article shows that both organizations have different strategies, alliance formations and ideologies in their activism. The differences between these organizations weaken their advocacy.
The political economy of unfree labor and the state: An Indonesian case study
Authors: Yusriza Benni
Published: June 2020

Employing the concept of unfree labor, this article explores the role of the state in reinforcing victims’ vulnerability and shaping the political economy of trafficking practices. Based on a case study of trafficking victims in Benjina and Ambon, Maluku Province, Indonesia, I argue that Indonesian authorities’ intervention was driven not by humanitarian interest, nor by the concern for the protection of migrant workers’ rights, but rather by the intent to advance a political and economic agenda against the Thai fishing industry. Consequently, the intervention ignored the exploitative relations of production that underpinned the vulnerability of victims, despite being conducted in the name of victim-protection and improving livelihoods.
Seeking Solitude After Being Ostracized: A Replication and Beyond
Authors: Ren Dongning , Wesselmann Eric D. , van Beest Ilja
Published: June 2020

Individuals may respond to ostracism by either behaving prosocially or antisocially. A recent paper provides evidence for a third response: solitude seeking, suggesting that ostracized individuals may ironically engage in self-perpetuating behaviors which exacerbate social isolation. To examine this counterintuitive response to ostracism, we conceptually replicated the original paper in three studies ( N = 1,118). Ostracism experiences were associated with preference for solitude across four samples (Study 1), and being ostracized increased participants’ desires for solitude (Studies 2 and 3). Extending beyond the original paper, we demonstrated that only the experience of being ostracized, but not ostracizing others or the feeling of conspicuousness, triggered the desire for solitude. Diverging from the original paper, trait extraversion did not moderate the effect of ostracism on solitude desires. Taken together, the current research provides additional and stronger empirical evidence that solitude seeking is a common response to ostracism.
Management Forecast Optimism During Credit Watch and Credit Rating Agencies’ Disciplinary Role
Authors: Hui Kai Wai , Liu Alfred Zhu , Zhang Yao
Published: June 2020

This study investigates management forecast optimism and credit rating agencies’ role in disciplining opportunistic managerial disclosures in the setting of credit watch reviews. Our analysis shows that managers are generally more likely to issue earnings forecasts and to optimistically bias their forecasts during credit watch periods than in non-watch periods. However, their forecast optimism declines when the rating agency involved has a stronger incentive or ability to monitor, such as when it has low conflict of interest or less difficulty detecting bias in disclosures. In such cases, the rating agency is more likely to penalize managers’ watch-period forecast optimism via unfavorable watch resolutions. Our study provides new evidence on opportunistic voluntary disclosures during credit-related events and credit rating agencies’ monitoring role (or lack thereof) in disciplining misrepresentation in voluntary disclosures.
Intergenerational Solidarity and Life Satisfaction among Empty-nest Older Adults in Rural China: Does Distance Matter?
Authors: Li Mengting , Luo Yaling , Li Penghui
Published: June 2020

Intergenerational solidarity plays a significant role in older adults’ psychological well-being, but it remains unclear whether the influence would vary by distance. This study aims to examine the moderating role of geographical proximity between intergenerational solidarity and life satisfaction. We interviewed 1,015 rural older adults in Sichuan, China. Life satisfaction was measured by Satisfaction with Life Scale. Five of the six dimensions of intergenerational solidarity were assessed: structural (geographical proximity), associational (contact frequency), functional (support exchange), affectual (emotional closeness), and normative (filial obligation). Multiple regression with interaction term was used. We found the effect of intergenerational solidarity (except associational solidarity) on life satisfaction was strongest for older adults with children living in the same city. Gender differences existed in the moderating effect of parent–child distance on the relationship between intergenerational solidarity and life satisfaction. Social services could focus on older adults with interprovincial migrant children and protect their well-being.
Attitudes toward Working Mothers and Work-Oriented Fathers in the U.S.
Authors: Kaufman Gayle , Bair Molly
Published: June 2020

While there is a wealth of research on gender ideology, most research focuses on attitudes toward women and women’s roles. This study aims to address the gap in our understanding of attitudes toward working fathers. Using the 2016 General Social Survey (GSS), we find more negative attitudes toward work-oriented fathers than working mothers. Results from multinomial logistic regression show that men, older individuals, Hispanics, and those who attend religious services more frequently are more likely to agree that both working mothers and work-oriented fathers are harmful to families. On the other hand, those whose mothers were employed when they were 16 years old and those who have a college or graduate degree are less likely to agree that only working mothers are harmful.
Taste and Smell Impairment in COVID‐19: An AAO‐HNS Anosmia Reporting Tool‐Based Comparative Study
Authors: Sayin İbrahim , Yaşar Kadriye Kart , Yazici Zahide Mine
Published: June 2020

Objective

To identify the taste and smell impairment in coronavirus disease 2019 (COVID‐19)–positive subjects and compare the findings with COVID‐19–negative subjects using the American Academy of Otolaryngology–Head and Neck Surgery (AAO‐HNS) Anosmia Reporting Tool.

Setting

Tertiary referral center/COVID‐19 pandemic hospital.

Study Design

Comparative study.

Subjects and Methods

After power analysis, 128 subjects were divided into 2 groups according to real‐time polymerase chain reaction (RT‐PCR) COVID‐19 testing results. Subjects were called via telephone, and the AAO‐HNS Anosmia Reporting Tool was used to collect responses.

Results

The mean age of the study group was 38.63 ± 10.08 years. At the time of sampling, rhinorrhea was significantly high in the COVID‐19–negative group, whereas those complaints described as “other” were significantly high in the COVID‐19–positive group. There was a significant difference in the smell/taste impairment rates of the groups (n = 46% [71.9%] for the COVID‐19–positive group vs n = 17 [26.6%] for the COVID‐19–negative group, P =. 001). For subjects with a smell impairment, anosmia rates did not differ between the groups. The rates of hyposmia and parosmia were significantly high in the COVID‐19–positive group. For the subjects with taste impairment, ageusia rates did not differ between groups. The rate of hypogeusia and dysgeusia was significantly high in the COVID‐19–positive group. Logistic regression analysis indicates that smell/taste impairment in COVID‐19–positive subjects increases the odds ratio by 6.956 (95% CI, 3.16‐15.29) times.

Conclusion

COVID‐19–positive subjects are strongly associated with smell/taste impairment.
Revaluation of Otolaryngologic Procedures With 10‐ and 90‐Day Global Periods in the Medicare Physician Fee Schedule
Authors: Rathi Vinay K. , Miller Ashley L. , Patel Urjeet A. , Varvares Mark A. , Bergmark Regan W. , Xiao Roy , Naunheim Matthew R.
Published: June 2020

A recent investigation by the Centers for Medicare and Medicaid Services (CMS) suggests that physicians provide fewer postoperative visits (POVs) than expected for procedures with 10‐ and 90‐day global periods. CMS is now contemplating revaluation of these procedures, which could result in lower Medicare payments to otolaryngologists. To estimate the impact of such reform on otolaryngologic procedures, we conducted a secondary subgroup analysis of CMS‐contracted research, which used claims‐based estimates of POVs to revalue procedures with 10‐ and 90‐day global periods. Among the top 10 highest volume procedures performed in 2018, the proportion of median physician‐reported to CMS‐expected POVs ranged between 0.0% (myringotomy ± ventilation tube insertion, mouth biopsy, and complex wound repair) and 40.0% (total thyroidectomy). The top 5 procedures accounted for nearly three‐quarters ($6.2 million and $8.6 million; 72.6%) of the estimated Medicare payment reduction. Further study is necessary to guide the development of equitable and effective payment reform.
When a romantic partner has a spinal cord injury: Caregiving tasks and resilience as moderators of support quality on psychosocial distress and relational closeness
Authors: Ledbetter Andrew M. , Carr Kristen , Lynn Gentry
Published: June 2020

Using a sample of 312 people in a romantic relationship with a partner who has a spinal cord injury (SCI), this study examined the separate and combined effects of caregiving tasks, resilience, and received support on the participant’s level of psychosocial distress. We also tested whether such distress might mediate the effect of the predictors on romantic relationship closeness. Results supported the beneficial effects of both resilience and receiving high-quality support, although the timing of the injury moderated these effects. Injuries sustained after relationship initiation particularly threaten well-being and closeness and, along with the burden of caregiving tasks, alter the extent to which received support and resilience are associated with health and relationship benefits. These results suggest that support providers should be sensitive to the context of the SCI and, for scholars, indicate the importance of further theorizing context in the theory of resilience and relational load.
Natural Experiment to Assess the Impacts of Street-Level Urban Design Interventions on Walkability and Business Activity
Authors: Said Maher , Geha Georges , Abou-Zeid Maya
Published: June 2020

This study uses a natural experiment in Beirut, Lebanon, to investigate the effects of a street-level urban design intervention that improved the walking environment through a wider sidewalk, removal of a parking lane, raised junctions, and other elements. This study analyzes the impacts on pedestrian flow, pedestrian satisfaction with the walking experience, commercial activity, and business managers’ attitudes. Difference-in-difference regressions suggest that the main effect of such interventions is not necessarily an increase in pedestrian traffic, but instead safer pedestrian maneuvering and a better walking experience. It is also found through descriptive analysis that while businesses and shops experience increased business post-intervention, noticeable dissatisfaction with the intervention is reported by managers and owners. It is hypothesized that this dissatisfaction is a result of the lengthy construction process renovating and refurbishing the street, and the removal of parking spaces. Policy recommendations are drawn for the mitigation of business managers’ concerns and the enhancement of the walking environment for the design of future similar interventions.
Reconsidering Reciprocal Length Patterns of the Anteromedial and Posterolateral Bundles of the Anterior Cruciate Ligament During In Vivo Gait
Authors: Englander Zoë A. , Wittstein Jocelyn R. , Goode Adam P. , Garrett William E. , DeFrate Louis E.
Published: June 2020

Background:

Some cadaveric studies have indicated that the anterior cruciate ligament (ACL) consists of anteromedial and posterolateral bundles that display reciprocal function with regard to knee flexion. However, several in vivo imaging studies have suggested that these bundles elongate in parallel with regard to flexion. Furthermore, the most appropriate description of the functional anatomy of the ACL is still debated, with the ACL being described as consisting of 2 or 3 bundles or as a continuum of fibers.

Hypothesis:

As long as their origination and termination locations are defined within the ACL attachment site footprints, ACL bundles elongate in parallel with knee extension during gait.

Study Design:

Descriptive laboratory study.

Methods:

High-speed biplanar radiographs of the right knee joint were obtained during gait in 6 healthy male participants (mean ± SD: body mass index, 25.5 ± 1.2 kg/m2; age, 29.2 ± 3.8 years) with no history of lower extremity injury or surgery. Three-dimensional models of the right femur, tibia, and ACL attachment sites were created from magnetic resonance images. The bone models were registered to the biplanar radiographs, thereby reproducing the in vivo positions of the knee joint. For each knee position, the distances between the centroids of the ACL attachment sites were used to represent ACL length. The lengths of 1000 virtual bundles were measured for each participant by randomly sampling locations on the attachment site surfaces and measuring the distances between each pair of locations. Spearman rho rank correlations were performed between the virtual bundle lengths and ACL length.

Results:

The virtual bundle lengths were highly correlated with the length of the ACL, defined as the distance between the centroids of the attachment sites (rho = 0.91 ± 0.1, across participants; P < 5 × 10-5). The lengths of the bundles that originated and terminated in the anterior and medial aspects of the ACL were positively correlated (rho = 0.81 ± 0.1; P < 5 × 10-5) with the lengths of the bundles that originated and terminated in the posterior and lateral aspects of the ACL.

Conclusion:

As long as their origination and termination points are specified within the footprint of the attachment sites, ACL bundles elongate in parallel as the knee is extended.

Clinical Relevance:

These data elucidate ACL functional anatomy and may help guide ACL reconstruction techniques.
Effects of a Universal Classroom Management Intervention on Middle School Students With or At Risk of Behavior Problems
Authors: Sinclair James , Herman Keith C. , Reinke Wendy M. , Dong Nianbo , Stormont Melissa
Published: June 2020

Universal interventions implemented in schools have the potential to impact large numbers of students on a multitude of behavioral and academic outcomes. In the context of a large group randomized controlled trial, the current study examined whether teacher-perceived student need for behavior support plans at baseline moderated the effects of a middle school universal classroom management training program, CHAMPS, which stands for Conversation, Help, Activity, Movement, Participation, and Success, on student outcomes. We hypothesized that students in CHAMPS classrooms who were identified by teachers at baseline as needing behavior support plans would have greater end-of-year improvements on behavior and academic outcomes relative to comparable youth in non-CHAMPS classrooms. Results indicated baseline teacher-perceived student behavior support need moderated some intervention outcomes; in particular, youth at risk in CHAMPS classrooms demonstrated improvements in concentration problems ( b = –.19) and communication arts outcomes ( b = .13) compared with youth at risk in control group classrooms. Implications of these findings and future research are discussed.
Stratégie de tarification par le revenue management dans le secteur hôtelier : réduire l’injustice perçue pour favoriser le consentement à payer
Authors: Méatchi Sourou , Camus Sandra
Published: June 2020

Dans un contexte de concurrence toujours exacerbée, la tarification par le revenue management (TRM) est devenue un outil stratégique pour les entreprises disposant de capacités contraintes. Cependant, en dépit de son intérêt considérable, des études montrent que la TRM fait l’objet de réactions mitigées de la part des consommateurs. L’objectif de cette recherche est de tester des leviers d’actions susceptibles de contribuer à réduire l’injustice perçue à l’égard de la TRM et ainsi, favoriser le consentement à payer (CAP). Deux échantillons quantitatifs (N1=325 ; N2=280) ont permis de valider les instruments de mesure des concepts mobilisés et tester deux modèles explicatifs de “fairness based pricing”. Les résultats montrent que l’équité et la transparence ont des effets individuels et d’interaction fort positifs sur la réduction des dimensions cognitives de l’injustice perçue et sur le renforcement du CAP. En revanche, les effets sur les dimensions affectives de l’injustice perçue ne sont pas validées dans les deux modèles testés.
Indicators of Social Competence and Social Participation Among US Children With Tourette Syndrome
Authors: Bitsko Rebecca H. , Danielson Melissa L. , Leeb Rebecca T. , Bergland Brita , Fuoco Morgan J. , Ghandour Reem M. , Lewin Adam B.
Published: June 2020

Children with Tourette syndrome often have behavioral and social difficulties, which may be associated with co-occurring mental, emotional, or behavioral disorders. This study investigated social competence, including behavioral problems and social skills, and social activities between children with and without Tourette syndrome using a nationally representative sample. In the 2007 National Survey of Children’s Health, parents reported on health care provider diagnosis of Tourette syndrome, co-occurring mental, emotional, or behavioral disorders, and indicators of social competence. Children aged 6-17 years with and without Tourette syndrome were compared. Most (78.7%) children with Tourette syndrome had a co-occurring mental, emotional, or behavioral disorder. Children with Tourette syndrome had significantly lower social competence, exhibited by higher levels of behavior problems (mean score 11.6 for Tourette syndrome and 9.0 for no Tourette syndrome) and lower levels of social skills (mean 15.3) than children without a Tourette syndrome diagnosis (mean 17.1); however, these associations were no longer significant after controlling for co-occurring mental, emotional, or behavioral disorders. Moderate to severe Tourette syndrome was associated with the highest ratings of behavioral problems and the lowest ratings of social skills. Children with and without Tourette syndrome were equally likely to participate in social activities; the difference for children with moderate to severe Tourette syndrome being less likely to participate in activities compared to children with mild Tourette syndrome had a chi-square test P value of .05. In conclusion, Tourette syndrome was associated with lower social competence, particularly for children with moderate to severe Tourette syndrome. Monitoring social functioning and co-occurring conditions among children with Tourette syndrome, and referral for evidence-based interventions when needed, may benefit overall health and functioning.
The Association Between Trauma Centrality and Posttraumatic Stress Among Syrian Refugees: The Impact of Cognitive Distortions and Trauma-Coping Self-Efficacy
Authors: Chung Man Cheung , Shakra Mudar
Published: June 2020

While research suggests that the war in Syria has led to a drastic re-evaluation of oneself and elevated psychiatric symptoms among Syrian refugees, little is known whether these psychological reactions might be influenced by maladaptive beliefs about oneself and the world and their ability to cope with the effect of the trauma. This study aimed to provide further evidence on the association between trauma centrality, posttraumatic stress, and psychiatric comorbidity, and examine whether cognitive distortions and trauma-coping self-efficacy would mediate the impact of trauma centrality on distress among Syrian refugees residing in Sweden. Four-hundred seventy-five Syrian refugees completed a demographic page, the Harvard Trauma Questionnaire, General Health Questionnaire-28, Centrality of Event Scale, Cognitive Distortion Scales, and trauma-coping self-efficacy. Results showed that trauma centrality was significantly correlated with posttraumatic stress disorder (PTSD) and psychiatric comorbidity after adjusting the effects of trauma exposure characteristics. Cognitive distortions mediated the impact of trauma centrality on the two distress outcomes; trauma-coping self-efficacy did not but was negatively correlated with outcomes. To conclude, the war in Syria changed self-perception, outlook on life, and identity among Syrian refugees. These changes were related to increased psychological symptoms especially for those who had distorted beliefs about themselves and the world. Refugees’ belief in the lack of ability to cope with the effect of the trauma impacted psychological distress independently of changes in self-perception.
Associations Between Nutrition Knowledge and Overall Diet Quality: The Moderating Role of Sociodemographic Characteristics—Results From the PREDISE Study
Authors: Carbonneau Elise , Lamarche Benoît , Provencher Véronique , Desroches Sophie , Robitaille Julie , Vohl Marie-Claude , Bégin Catherine , Bélanger Mathieu , Couillard Charles , Pelletier Luc , Bouchard Luigi , Houle Julie , Langlois Marie-France , Corneau Louise , Lemieux Simone
Published: June 2020

Purpose:

To assess how nutrition knowledge is associated with global diet quality and to investigate whether sociodemographic characteristics (ie, sex, age, education, income, marital status, and living with children or not) moderate this association.

Design:

Cross-sectional web-based study.

Participants:

The PREDISE study aims at identifying correlates of adherence to healthy eating guidelines in French-speaking adults from the Province of Quebec, Canada.

Subjects:

A probability sample of 1092 participants (50% female).

Measures:

The Nutrition Knowledge Questionnaire and 24-hour food recalls from which the Canadian Healthy Eating Index (C-HEI) was calculated.

Analysis:

Multiple linear regressions performed to assess how nutrition knowledge is associated with the C-HEI. Interaction terms tested to evaluate whether sociodemographic characteristics moderate the association between nutrition knowledge and the C-HEI.

Results:

Nutrition knowledge (B = 0.141 [95% CI: 0.075-0.208], P < .0001) was identified as a significant correlate of the C-HEI. Education significantly moderated the association between nutrition knowledge and the C-HEI ( P interaction = .0038), with a significative association among participants with a lower education level (B = 0.295 [95% CI: 0.170-0.421], P < .0001) but not among participants with a higher education level (B = 0.077 [95% CI: −0.004 to 0.157], P = .06). Whether participants lived with or without children also significantly moderated the association ( P interaction = 0.0043); nutrition knowledge was associated with the C-HEI only in participants who were not living with children (B = 0.261 [95% CI: 0.167 to 0.355], P < .0001).

Conclusion:

This study suggests that the association between nutrition knowledge and adherence to healthy eating guidelines is not the same in different subgroups of the population. Interventions aiming at increasing nutrition knowledge may be a promising approach to improve diet quality, especially among individuals with a lower education.
Preparation of tough, high modulus, and creep-resistant PS/SIS/halloysite blend nanocomposites
Authors: Tekay Emre
Published: June 2020

In this work, polystyrene (PS)/poly(styrene-b-isoprene-b-styrene) (SIS)/organophilic halloysite nanotube (Org-HNT) blend nanocomposites were produced by melt compounding technique. The significant improvements in both toughness and impact strength values were obtained in PS/SIS blends containing 20%, 30%, and 40% SIS elastomer as compared to neat PS. Among them, PS-30SIS blend with a co-continuous morphology exhibited moderate tensile and impact properties and its nanocomposites having 3, 5, 7 and 10 phr Org-HNT were prepared through the melt mixing method. All the nanocomposites exhibited continuous/fibrillar morphologies with smaller elastomer domains and higher tensile modulus and toughness as compared to PS-30SIS blend. Among them, the nanocomposite having 7 phr Org-HNT and 30% SIS phase (7H-30SIS) exhibited the highest impact strength with enhanced tensile properties. The same nanocomposite exhibited about 21% and 100% increments in the modulus and toughness in comparison to its blend, respectively. The 7H-30SIS nanocomposite increased storage moduli of PS-30SIS blend at glass transition regions of both polyisoprene and PS phases and also at room temperature. Moreover, the rubbery storage moduli of the nanocomposites were found to be about 37% and 53% higher for 7 and 10 phr Org-HNT loaded nanocomposites, respectively, in comparison with that of PS-30SIS blend. The creep deformation and permanent deformation of the blend both decreased via introduction of the nanotubes which is in agreement with aforementioned improvements in the stiffness.
Frailty and Social Isolation: Comparing the Relationship between Frailty and Unidimensional and Multifactorial Models of Social Isolation
Authors: Maltby John , Hunt Sarah A. , Ohinata Asako , Palmer Emma , Conroy Simon
Published: June 2020

Objective: The aim of the study was to compare uni- and multidimensional models of social isolation to improve the specificity of determining associations between social isolation and frailty. Methods: The study included participants aged ≥60 years from the English Longitudinal Study of Ageing assessed for social isolation and frailty (frailty index and Fried phenotype) over a 4-year period. Factor analysis assessed whether social isolation was multidimensional. Multiple regression analysis was used to assess specificity in associations between social isolation and frailty over time. Results: Social isolation comprises social isolation from nuclear family, other immediate family, and wider social networks. Over time, social isolation from a wider social network predicted higher frailty index levels, and higher frailty index and Fried phenotype levels predicted greater social isolation from a wider social network. Discussion: Social isolation is multidimensional. The reciprocal relationship between social isolation from wider social networks and accumulating frailty deficits, and frailty as a clinical syndrome influencing social isolation from social networks is discussed.
Investigations on friction stir joining of 3D printed parts to overcome bed size limitation and enhance joint quality for unmanned aircraft systems
Authors: Tiwary Vivek Kumar , Ravi NJ , Arunkumar P , Shivakumar S , Deshpande Anand S , Malik Vinayak R
Published: June 2020

3D printing technology is making its mark in automotive, aerospace, and bio-medical-related industries. It is considered a viable option for the direct manufacturing of final parts. However, it is not possible to print longer parts in a single attempt due to the bed size limitation of printers. This problem can be addressed by employing a polymer joining technique as a secondary operation. Moreover, low mechanical strength and inferior geometrical qualities like the flatness of the joined parts restrict its real-time industrial application. Here, an attempt is made to join a longer part (typical of an aircraft wing) using friction stir welding technique. Joining was performed on 3D printed similar/dissimilar thermoplastic parts. Tensile test results showed that friction stir welding of 3D printed parts (for both similar/dissimilar) produced relatively weaker joints compared to the base material. Various important process parameters of 3D printing and friction stir welding technique, namely part infill percentage, material combination, tool rotational speed, traverse speed, and tool pin taper angle were optimized by means of ANOVA. Optimization was aimed at maximizing the weld strength, elongation, hardness, and desired flatness. The results suggested that the material combination and tool pin taper angle play a significant role in the weld's strength as well as its geometric properties (flatness). The results were validated by adopting the optimized parameters for successful joining of the wing section of an unmanned aerial vehicle. A span of 320 mm, with a metrological acceptable flatness value of 0.41 µ/m could be successfully achieved on an existing 3D printer whose bed size limit was 240 mm.
Local high edge observation for the bonding line monitoring of a complex composite beam
Authors: Ciminello Monica , Galasso Bernardino , Apuleo Gianvito , Shoam Shay , Concilio Antonio
Published: June 2020

The most part of defects in composite structures carrying attached subelements is the disbond at the interface, as the skin/stringer sections. This is sometimes due to a nonoptimal manufacturing process or sometimes due to accidental object impacts during service. It has been verified that structural discontinuities within an elastic medium under mechanical loads can cause analogous discontinuities within the strain field. Starting from this analysis, the present work investigates the effect of artificially induced kissing bond areas just at the in the skin–stiffener interface of an aeronautical complex composite beam. This research uses longitudinal strain values, acquired at the locations where distributed fiber optic sensors are installed. The applied methodology uses different strain-based features providing local high edge observation both in time and spatial domains. Their autocorrelations are, in the end, computed to improve signal-to-noise ratio. The local high edge observation algorithm is proposed that proves its capability to monitor disbond being at the same time load and baseline independent.
Study of plastically deformed region underneath the ball in indentation tests and evaluation of mechanical properties of materials through finite element simulation and a hybrid algorithm
Authors: Samal Mahendra K , Syed A , Khatri RN , Chattopadhyay J
Published: June 2020

Ball indentation technique has been studied extensively in literature and it has been widely applied to determine mechanical properties of different materials because of simplicity and minimal requirement of material for the tests. Originally, the material deformation was represented in terms of a representative strain, which is a non-dimensional form of indentation diameter and a representative stress, which again is the instantaneous mean pressure multiplied by some empirical factors. It is known that the state of deformation as well as stress beneath the ball is multiaxial in nature in a ball indentation test. In this work, a new hybrid algorithm for estimation of equivalent stress and equivalent plastic strain during the process of indentation in the most stressed location beneath the ball has been developed. The algorithms uses experimental load–indentation data as well as the multiaxial stress and strain parameters obtained from 2D axisymmetric elastic-plastic finite element simulations. The stress and strain multiaxial parameters are functions of applied load, material yield stress and strain hardening exponents. The algorithm is iterative in nature and uses suitable initial guess values for material yield stress and strain hardening exponents and it converges very quickly. This method can be applied to determine the material stress–strain curve for a wide range of equivalent plastic strain, yield stress as well as plastic strain hardening exponent of the engineering materials. The data points of load vs. indentation depth as obtained directly from the ball indentation tests can be used in the new algorithm without the need for conducting unloading during the test. To illustrate the new scheme, two case studies have been presented where the results from the proposed new method have been compared with those of the existing method in literature and tensile test data to check the accuracy.
Robust H∞ Takagi–Sugeno fuzzy output-feedback control for differential speed steering vehicles
Authors: Oke Paul , Nguang Sing Kiong
Published: June 2020

This paper studied the modelling and control of four-wheel independently driven electric vehicles using differential speed steering. The Takagi–Sugeno fuzzy modelling approach represents the nonlinearities of the four-wheel independently driven electric vehicle state variables in several system models. The proposed controller design is a robust Takagi–Sugeno fuzzy output-feedback control based on a fuzzy Lyapunov function approach. More precisely, the Lyapunov function is chosen to be dependent on the membership functions. Sufficient conditions for the existence of the robust Takagi–Sugeno fuzzy controller are given in terms of linear matrix inequality constraints. The designed parameters are tested by simulating the four-wheel independently driven electric vehicles under varying operating conditions. The simulation results underscore the robustness and disturbance rejection importance of the proposed controller, which is then contrasted to better highlight the improved performance of the proposed approach over a fixed robust controller design.
Ecosystem shifts at two mid-Holocene tipping points in the alpine Lake Son Kol (Kyrgyzstan, Central Asia)
Authors: Laug Andreas , Schwarz Anja , Lauterbach Stefan , Engels Stefan , Schwalb Antje
Published: June 2020

Tipping points can be defined as critical ecosystem thresholds that start self-enforced dynamics pushing systems into new stable states. Many lake ecosystems of arid Central Asia are sensitive to hydrological changes as they are located at the intersection of the influence of the dry Siberian Anticyclone and the relatively humid mid-latitude Westerlies, and their sediment records can be used to study past tipping points. We studied subfossil chironomid remains preserved in a ca. 6000-year-long sediment record from the Central Asian lake Son Kol (Central Kyrgyzstan) to reconstruct past ecosystem dynamics. Our results show abrupt transitions from a chironomid fauna dominated by macrophyte-associated, salinity-indicating taxa, to a vegetation-independent fauna, and subsequently to a macrophyte-associated, freshwater-indicating fauna. A comparison of the chironomid-based environmental reconstruction to other proxy indicators from the same record suggests a phase of increased Westerly strength starting about 4900 cal. yr BP. This increase led to enhanced precipitation and sediment fluxes into the lake, which in turn led to high turbidity levels and consequently to a macrophyte collapse causing abrupt changes in the chironomid fauna. At 4300 cal. yr BP, a weakening of the Westerlies in combination with higher lake levels led to lower turbidity and ultimately to the recovery of the macrophyte population and associated changes in the chironomid assemblage. These two sequences of events show how the occurrence of a gradual change in an external trigger (Westerlies) can trigger a cascade of within-lake processes (turbidity, macrophyte density) and may ultimately lead to an abrupt reorganization of the ecosystem (chironomid fauna), providing models for tipping points.
IFNβ signaling inhibits osteogenesis in human SLE bone marrow
Authors: Gao Lin , Liesveld Jane , Anolik Jennifer , Mcdavid Andrew , Looney Richard John
Published: June 2020

Background

Bone marrow mesenchymal stem cells are multipotent adult stem cells that can differentiate into osteoblasts, adipocytes, and chondrocytes. Our recently published data demonstrate that systemic lupus erythematous bone marrow mesenchymal stem cells produce increased quantities of interferon β based on a positive feedback loop involving the innate signaling molecule mitochondrial antiviral signaling protein. Moreover, this pathway contributes to human systemic lupus erythematous bone marrow mesenchymal stem cell senescence-like features. Here we investigate the differentiation defects of systemic lupus erythematous bone marrow mesenchymal stem cells and the potential for therapeutic interventions.

Methods

The six systemic lupus erythematous patients recruited in this study satisfy the American College of Rheumatology 1997 classification criteria for systemic lupus erythematous. Systemic Lupus Erythematous Disease Activity Index-2K was used to determine disease activity. Systemic lupus erythematous bone marrow mesenchymal stem cells were isolated with Ficoll centrifugation and phenotyped using flow cytometry. In vitro studies included real-time polymerase chain reaction and western blotting.

Results

We compared six age-paired bone marrow aspirates from healthy controls and systemic lupus erythematous patients. Systemic lupus erythematous bone marrow mesenchymal stem cells display significantly reduced alkaline phosphatase staining, as well as reduced expression of osteogenic markers alkaline phosphatase, Runt-related transcription factor 2, and bone sialoprotein. When healthy bone marrow mesenchymal stem cells were treated with interferon β for 6 hours, expression of these same osteogenic markers was markedly reduced. Conversely the application of interferon β neutralizing antibody enhanced the expression of osteoblastogenesis markers. When the underlying mechanisms for interferon β inhibition of osteoblastogenesis were investigated, we found that IFNβ pre-treatment activates the inhibitory Smad6 and Smad7 expression through JAK1/STAT1, leading to reduced Smad1 phosphorylation and nuclear translocation.

Conclusions

Our present work suggests that interferon β affects osteogenesis. By revealing the essential role of interferon β on systemic lupus erythematous bone marrow mesenchymal stem cell differentiation, our study sheds light on systemic lupus erythematous pathogenesis and provides a new potential therapeutic target for the bone complications found in systemic lupus erythematous.
Effects of defects and functional groups on graphene and nanotube thermoset epoxy-based nanocomposites mechanical properties using molecular dynamics simulation
Authors: Haghighi Mahmoud , Khodadadi Ali , Golestanian Hossein , Aghadavoudi Farshid
Published: June 2020

In this article, several thermoset epoxy-based nanocomposites are simulated using molecular dynamics (MD) simulation. Epoxy resin with 75% crosslinking ratio is modeled first and its properties are used as the matrix material mechanical properties. The effects of defects and functional groups on carbon nanotube- and nanographene-reinforced epoxy nanocomposites are investigated. To achieve our goals, various types of defects and functional groups are created on graphene and nanotube in the MD models. The defects consist of Stone–Wales, vacancy, and Adatom. In addition, functional groups consist of O, OH, COOH, and NH2. Mechanical properties of nanocomposites are determined and compared. Moreover, nanocomposites consisting of continuous and short reinforcements are modeled to investigate the effects of reinforcement length on nanocomposite mechanical properties. Numerical results show that defects and functional groups reduce the elastic modulus of the nanofillers and nanocomposites in continuous nanofiller-reinforced epoxy. However, in nanocomposites consisting of short nanofillers, defects and functional groups have mixed effects on nanocomposite mechanical properties.
Conscientiousness in Game-Based Learning
Authors: Yi Liu , Zhou Qiqi , Xiao Tan , Qing Ge , Mayer Igor
Published: June 2020

Background. An increasing number of studies support a mediating influence of personality on video-game preferences and player experiences, and in particular, traits associated with playfulness, such as extraversion. Educational institutions, however, tend to reward serious personality traits, such as conscientiousness.

Aim.To discern how students respond to Game-Based Learning (GBL) in the classroom, and to understand if and how conscientiousness mediates GBL, we performed a field study at a leading university of technology in northeast China.

Method. In May 2019, 60 bachelor and executive students in public-administration studies consecutively played two digital serious games, TEAMUP (multiplayer) and DEMOCRACY3 (single player). Data accrued through surveys with pregame measurements of personality (conscientiousness), mediating factors (motivation, player experience), learning effectiveness (cognitive and non-cognitive learning), and GBL acceptance.

Results. Analysis showed a strong overall learning effect for both games. Conscientiousness significantly related to cognitive learning in both games and noncognitive learning in the multiplayer game only. Conscientiousness also significantly related to player experiences in the multiplayer game. Furthermore, the conscientiousness facet of perfectionism was a dominant factor in player experience and learning. We discuss the findings in light of several aspects around GBL that require more attention and research, especially that, alongside other factors, conscientiousness may be an important dimension to consider in the design and implementation of GBL in education, and GBL can have a positive role in the modernization of education in non-Western countries.
Learning to Become an Inclusive Teacher
Authors: Van de Ven Andy
Published: June 2020

In this essay I share some personal lessons learned on becoming a more inclusive teacher, with the hope that they stimulate us to be reflexive and share our learning experiences. Inclusive teaching is a movement in K-12 public schools and higher education that aims to cultivate a learning environment where all students are treated equitably, have equal access to learning, and feel valued and supported in their learning.
Veto Threat Bargaining with a Bicameral Congress
Authors: Guenther Scott M. , Kernell Samuel
Published: June 2020

According to the conventional view, presidents are largely bereft of influence with an opposition-controlled Congress. Congress sends them legislation with a “take it or leave it” choice that maximizes the preferences of the opposition majority while minimizing presidents’ preferences. To extricate themselves from this bind, presidents threaten vetoes. Past research suggests that their efforts largely fail, however, for two model-driven reasons: first, veto threats amount to minimally informative “cheap talk,” and second, Congress is a unitary actor with firm control over its agenda. We relax both assumptions, bringing veto rhetoric into a setting more closely resembling real-world conditions. Presidents transmit credible veto threats to a heterogeneous, bicameral Congress where chamber rules enable the minority party to wield some influence over legislation. Examining the legislative histories of all veto-threatened bills passed between 1985 and 2016, we confirm that veto threats ward off about half of veto-targeted legislative provisions—a far greater share than for comparable unthreatened provisions. The House of Representatives is more likely to introduce and pass legislation objectionable to presidents and the Senate is more likely to accommodate presidents, findings consistent with the textbook description of the modern bicameral Congress.