Proximodistal exploration in motor learning as an emergent property of optimization

To harness the complexity of their high‐dimensional bodies during sensorimotor development, infants are guided by patterns of freezing and freeing of degrees of freedom. For instance, when learning to reach, infants free the degrees of freedom in their arm proximodistally, that is, from joints that are closer to the body to those that are more distant. Here, we formulate and study computationally the hypothesis that such patterns can emerge spontaneously as the result of a family of stochastic optimization processes, without an innate encoding of a maturational schedule. In particular, we present simulated experiments with an arm where a computational learner progressively acquires reaching skills through adaptive exploration, and we show that a proximodistal organization appears spontaneously, which we denote PDFF (Proximo Distal Freezing and Freeing of degrees of freedom). We also compare this emergent organization between different arm morphologies—from human‐like to quite unnatural ones—to study the effect of different kinematic structures on the emergence of PDFF.     

Is ZF a hack?: Comparing the complexity of some (formalist interpretations of) foundational systems for mathematics

This paper presents Automath encodings (which are also valid in LF/λP) of various kinds of foundations of mathematics. Then it compares these encodings according to their size, to find out which foundation is the simplest.

The systems analyzed in this way are two kinds of set theory (ZFC and NF), two systems based on Church's higher order logic (Isabelle/Pure and HOL), three kinds of type theory (the calculus of constructions, Luo's extended calculus of constructions, and Martin-Löf's predicative type theory) and one foundation based on category theory.

The conclusions of this paper are that the simplest system is type theory (the calculus of constructions), but that type theories that know about serious mathematics are not simple at all. In that case the set theories are the simplest. If one looks at the number of concepts needed to explain such a system, then higher order logic is the simplest, with twenty-five concepts. On the other side of the scale, category theory is relatively complex, as is Martin-Löf's type theory.

(The full Automath sources of the contexts described in this paper are one the web at http://www.cs.ru.nl/~freek/zfc-etc/.)     

Women want taller men more than men want shorter women

Physical characteristics, such as height, play an important role in human mate preferences. Satisfaction with one’s own height and one’s partner height seem likely to be related to these preferences. Using a student sample (N = 650), we show that women are not only more selective, but also more consistent, than men, in their partner height preferences. Women prefer, on average, a larger height difference between themselves and their partner (i.e. males being much taller than themselves) than men do. This effect is even more pronounced when examining satisfaction with actual partner height: women are most satisfied when their partner was 21 cm taller, whereas men are most satisfied when they were 8 cm taller than their partner. Next, using data from our sample and that of a previously published study (N = 52,677), we show that for men, height is more important to the expression of satisfaction with one’s own height than it is for women. Furthermore, slightly above average height women and tall men are most satisfied with their heights. We conclude that satisfaction with one’s own height is at least partly a consequence of the height preference of the opposite sex and satisfaction with one’s partner height.     

Factors Associated with Providers’ Work Engagement and Burnout in Homeless Services: A Cross‐national Study

The complexity of homeless service users’ characteristics and the contextual challenges faced by services can make the experience of working with people in homelessness stressful and can put providers’ well‐being at risk. In the current study, we investigated the association between service characteristics (i.e., the availability of training and supervision and the capability‐fostering approach) and social service providers’ work engagement and burnout. The study involved 497 social service providers working in homeless services in eight different European countries (62% women; mean age = 40.73, SD = 10.45) and was part of the Horizon 2020 European study “Homelessness as Unfairness (HOME_EU).” Using hierarchical linear modeling (HLM), findings showed that the availability of training and supervision were positively associated with providers’ work engagement and negatively associated with burnout. However, results varied based on the perceived usefulness of the training and supervision provided within the service and the specific outcome considered. The most consistent finding was the association between the degree to which a service promotes users’ capabilities and all the aspects of providers’ well‐being analyzed. Results are discussed in relation to their implications for how configuration of homeless services can promote social service providers’ well‐being and high‐quality care.     

Homeless Adults’ Recovery Experiences in Housing First and Traditional Services Programs in Seven European Countries

Across Europe, as governments turn to housing-led strategies in attempts to reverse rising rates of homelessness, increasing numbers of Housing First (HF) programs are being implemented. As HF programs become more widespread, it is important to understand how service users experience them compared to the more prevalent traditional treatment-first approach to addressing long-term homelessness. Although there is a large body of research on service users’ experiences of Housing First compared to treatment-first in North American contexts, comparatively less is known about how these two categories of homeless services are experienced in the European context. In a correlational and cross-sectional study, part of a larger examination of homelessness in Europe, participants (n = 520) engaged with either HF (n = 245) or traditional services (TS; n = 275) programs in seven countries completed measures of their experiences of services (consumer choice, housing quality, and service satisfaction) and recovery (time in independent housing, psychiatric symptoms, and community integration). Across the seven countries, participants engaged with HF programs reported experiencing more consumer choice, better perceived housing quality, and more satisfaction with services than participants engaged in TS programs. Participants in HF programs also reported a greater proportion of time in independent accommodation, fewer psychiatric symptoms, and more community integration. Varying patterns of association between experiences of services and recovery outcomes were observed. Findings indicate HF consistently predicts greater recovery than TS across diverse sociopolitical and economic contexts. Implications of findings for configurations of homeless services and homeless services policy are discussed.     

High and mighty: Height increases authority in professional refereeing

Throughout the animal kingdom, larger males are more likely to attain social dominance. Several lines of evidence suggest that this relationship extends to humans, as height is positively related to dominance, status and authority. We hypothesized that height is also a determinant of authority in professional refereeing. According to the International Football Association Board, FIFA, football ("soccer") referees have full authority to enforce the laws of the game and should use their body language to show authority and to help control the match. We show that height is indeed positively related to authority status: referees were taller than their assistants (who merely have an advisory role) in both a national (French League) and an international (World Cup 2010) tournament. Furthermore, using data from the German League, we found that height was positively associated with authoritative behavior. Taller referees were better able to maintain control of the game by giving fewer fouls, thereby increasing the "flow of the game". Referee height was also positively associated with perceived referee competence, as taller referees were assigned to matches in which the visiting team had a higher ranking. Thus, height appears to be positively related to authority in professional refereeing.     

The image of Muhammad in The Message,the first and only feature film about the Prophet of Islam

In 1976 The Message, the first feature film about Muhammad, had its premiere. It was a very special film because as a result of the restrictions imposed by some prominent Muslim legal scholars, the Prophet was not depicted, nor his wives nor his cousin ^cAlī. After an analytical impression of the contents of the film, the article discusses the relationship between the image of Muhammad in The Message and the pictures of the Prophet delineated by Muslim tradition and modern biographies of him. It then considers some new declarations made by Muslim religious authorities in 2002 and 2004 about films dealing with the life of the Prophet. Finally attention is given to the consequences of the rules announced by Muslim religious scholars concerning the image of the Prophet and to the acceptance of such an image by non-Muslims.     

Parental bond and life course transitions from adolescence to young adulthood

In this study the effects of life course transitions in adolescence and young adulthood (leaving the parental home, living together with a partner,entering parenthood, and becoming financially independent) on the parent-child bond are investigated. Data are presented from a three-wave study of 1,064 adolescents and young adults (aged 12-24 years at Wave 1) over a six-year period. As the youth in this study proceeded through the life course, they tended to report a closer parental bond. However, this age-related effect was counterbalanced by a tendency toward a weakened bond with parents following departure from the parental home. Results are in line with individuation theory, which contends that parent-child relationships become less close as a result of transitions leading to more autonomy.     

Combining total laparoscopic hysterectomy and bilateral salpingo-oophorectomy with subcutaneous mastectomy in trans men: The effect on safety outcomes

Abstract

Background: Masculinizing mastectomy is the most requested gender affirming surgery (GAS) in trans men, followed by genital GAS. Mastectomy and total laparoscopic hysterectomy, with or without bilateral salpingo-oophorectomy (TLH?±?BSO), can both be performed in one single operation session. However, data on complication rates of the combined procedure is scarce and no consensus exists on the preferred order of procedures.

Aims: To compare safety outcomes between mastectomy performed in a single procedure with those when performed in a combined procedure and assess whether the order of procedures matters when they are combined.

Methods: A retrospective chart review was performed of trans men who underwent masculinizing mastectomy with or without TLH?±?BSO in a combined session. The effects of the surgical procedure on complication and reoperation rate of the chest were assessed using logistic regression.

Results: In total, 480 trans men were included in the study. Of these, 212 patients underwent the combined procedure. The gynecological procedure was performed first in 152 (71.7%) patients. In the total sample, postoperative hematoma of the chest occurred in 11.3%; 16% in the combined versus 7.5% in the single mastectomy group (p?=?0.001). Reoperations due to hematoma of the chest were performed in 7.5% of all patients; 10.8% in the combined versus 4.9% in the single mastectomy group (p?=?0.017). The order of procedures in the combined group had no significant effect on postoperative hematoma of the chest (p?=?0.856), and reoperations (p?=?0.689).

Conclusion: Combining masculinizing mastectomy with TLH?±?BSO in one session was associated with significantly more hematoma and reoperations compared with separately performing mastectomy. This increased risk of complications after a combined procedure should be considered when deciding on surgical options. The order of procedures in a combined procedure did not have an effect on safety outcomes.