Generating a smallest binary tree by proper selection of the longest edges to bisect in a unit simplex refinement

In several areas like global optimization using branch-and-bound methods for mixture design, the unit n-simplex is refined by longest edge bisection (LEB). This process provides a binary search tree. For \(n>2\), simplices appearing during the refinement process can have more than one longest edge (LE). The size of the resulting binary tree depends on the specific sequence of bisected longest edges. The questions are how to calculate the size of one of the smallest binary trees generated by LEB and how to find the corresponding sequence of LEs to bisect, which can be represented by a set of LE indices. Algorithms answering these questions are presented here. We focus on sets of LE indices that are repeated at a level of the binary tree. A set of LEs was presented in Aparicio et al. (Informatica 26(1):17–32, 2015), for \(n=3\). An additional question is whether this set is the best one under the so-called \(m_k\)-valid condition.     

Almost the same stories: narrative patterns in EU treaty referendums

ABSTRACT

The article analyses narratives that favoured or opposed European integration in three referendum debates held during the constitutional process of the 2000s: in France and the Netherlands in 2005 (Constitutional Treaty) as well as the first vote in Ireland on the Lisbon Treaty in 2008. In all debates examined, speakers used similar narratives of European integration. While most narrative patterns have transnational character, however, they are also remarkably country-specific. They depend on the specific cultural context and the social positions of the speakers articulating them.     

A study of significance of racial and athletic identification on educational perceptions among African American male college athletes

Abstract

The purpose of this study was to analyze the racial and athletic identities of African American male college athletes to determine how the identities might impact the athletic and educational potential and performance of this specific group of college athletes. The study revealed that participants who responded negatively to a poor athletic performance were more likely to have lower levels of academic self-concept. In contrast, college athletes who highly identified with their racial group were more likely to have higher levels of academic self-concept. Overall, the findings reveal the intricacies and complexities of being an African American college student and athlete at predominantly white institutions (PWIs) in the US. As such, the article details the implications of the findings as they relate to African American culture, American sports culture, and higher education realities.     

“It’s like this Myth of the Supernegro”: resisting narratives of damage and struggle in the neoliberal educational policy context

As pathologizing, racialized, and patriarchal rhetoric undergirds neoliberal education reform, deficit narratives characterize the education of Black youth. Such narratives present deep challenges for educational policy and community-based educational spaces. This article explores the ways in which community-based educators resist narratives of damage and struggle in their own personal and professional narratives in order to prevent the cycle of deficit-oriented discourse that follow Black youth through myriad educational spaces. By situating the narratives of community-based educators within a broader policy context shaped by race, class, and gender, this article illustrates the challenges that arise for community-based educators that seek to frame Black youth beyond deficit narratives and who avoid framing themselves as heroes and saviors of Black youth.     

Engaging with Comparative Risk Appraisals: Public Views on Policy Priorities for Environmental Risk Governance

Communicating the rationale for allocating resources to manage policy priorities and their risks is challenging. Here, we demonstrate that environmental risks have diverse attributes and locales in their effects that may drive disproportionate responses among citizens. When 2,065 survey participants deployed summary information and their own understanding to assess 12 policy‐level environmental risks singularly, their assessment differed from a prior expert assessment. However, participants provided rankings similar to those of experts when these same 12 risks were considered as a group, allowing comparison between the different risks. Following this, when individuals were shown the prior expert assessment of this portfolio, they expressed a moderate level of confidence with the combined expert analysis. These are important findings for the comprehension of policy risks that may be subject to augmentation by climate change, their representation alongside other threats within national risk assessments, and interpretations of agency for public risk management by citizens and others.     

Can Clinical Skills Be Taught Online? Comparing Skill Development Between Online and F2F Students Using a Blinded Review

This study compared the development of clinical assessment and intervention skills between students enrolled in a face-to-face (F2F) or an asynchronous online clinical social work class. All students from three semesters of F2F (n = 74) and online (n = 78) sections of an MSW clinical class taught by the same instructor were included. Two assignments were used to compare students: an assessment and treatment plan of a fictional case and a digital role-play. A doctoral student who was blinded to the course delivery mechanism graded the role-play. After controlling for baseline differences in age, there were no differences between online and F2F students in skill demonstration. It appears clinical skills can be taught as effectively online as in F2F situations based on blinded review of role-plays.     

Household Debt and Adult Depressive Symptoms in the United States

This study used data from Waves 1 (1987–1989) and 2 (1992–1994) of the National Survey of Families and Households in the United States and a series of regression models, some of which included individual-specific fixed effects, to estimate associations of particular types and levels of debt with adult depressive symptoms. Results suggest that household debt is positively associated with greater depressive symptoms. However, this association appears to be driven by short-term (unsecured) debt; we found little evidence of associations with depressive symptoms for mid- or long-term debt. The link between short-term debt and depressive symptoms persisted with alternative estimation strategies, including defining debt in absolute and relative terms. Furthermore, this association was particularly concentrated among 51–64 year-old adults, those with a high school education or less, and those who were not stably married throughout the observation period. These findings suggest that short-term debt may have an adverse influence on psychological wellbeing, particularly for those who are less educated, approaching retirement age, or unmarried.     

Common urban birds continue to perceive predator calls that are overlapped by road noise

Recent studies suggest that songbird communication is negatively affected by anthropogenic noise. However, much of the current literature focuses on inter- and intra-sexual communication. Songbirds also use acoustic cues for many other functional behaviors. One example associated with fitness consequences is the identification of predatory threats through acoustic cues. To test the effect of anthropogenic noise on detection of acoustic cues, we compared the rates of seven anti-predator behavioral responses in urban dwelling songbirds foraging at bird feeders when exposed to playback of calls from predatory Cooper’s hawks under quiet conditions, and when overlapped with road noise. Only a single behavior, freeze response, decreased significantly when calls were overlapped with noise. However, freeze responses occurred in only a small percentage of playback trials, raising some question regarding the biological relevance of this observed difference. Overall, our results suggest that common urban songbirds are relatively successful at perceiving acoustic signals associated with predator presence. Whether this ability is commonplace amongst songbird species is unknown and warrants additional study. However, if this trait is not widespread, it may be an additional characteristic determining which bird species can inhabit noisy areas.

     

Assessing the contribution of fallen autumn leaves to airborne fungi in an urban environment

Urban Ecosystems - Many street trees in urban areas are deciduous and drop leaves during autumn. These leaves are a potential growing substrate for fungi, which when aerosolized and inhaled, can...