Tearing Out the Income Tax by the (Grass)Roots

Landscapes are increasingly fragmented, and conservation programs have started to look at network approaches for maintaining populations at a larger scale. We present an agent-based model of predator–prey dynamics where the agents (i.e. the individuals of either the predator or prey population) are able to move between different patches in a landscaped network. We then analyze population level and coexistence probability given node-centrality measures that characterize specific patches. We show that both predator and prey species benefit from living in globally well-connected patches (i.e. with high closeness centrality). However, the maximum number of prey species is reached, on average, at lower closeness centrality levels than for predator species. Hence, prey species benefit from constraints imposed on species movement in fragmented landscapes since they can reproduce with a lesser risk of predation, and their need for using anti-predatory strategies decreases.authorCount :

A socio-ecological model of agency: The role of structure and agency in shaping education and employment transitions in England

This study examines the role of structural and agentic resources in shaping school-to-work transitions in England. We ask to what extent are young people able to steer the course of their lives despite the constraining forces of social structure, and how satisfied are they with their lives following the completion of compulsory schooling. Drawing on data from the Longitudinal Study of Young People in England we use sequence analysis of monthly activity data to identify differences in the timing and sequencing of education and employment transitions. We identified six distinct pathways, differentiating between an academic track, three pathways involving further education and training, as well as a work-focused transition and a group of young people who were over a long period not in education or training (NEET). The findings suggest that not all young people are inclined to follow an academic track and instead select into pathways involving vocational training or further education, enabling them to experience competence and life satisfaction. For others (about one in 10), however, the lack of socioeconomic and psycho-social resources is too overwhelming and they encounter long-term experience of NEET or are not able to transform their educational credentials into employment opportunities. The findings highlight that in addition to considering structural constraints it is important to conceptualise the role of the agent for a better understanding of variations in youth transitions

'A fish out of water?' The therapeutic narratives of class change

Young people from working class backgrounds remained mostly excluded from the widening educational participation which characterised postwar Britain. Based on 20 semi-structured interviews which were part of a wider study about ‘Social Participation and Identity’ (2008–2009), this article explores the unusual learning trajectories of a group of working class adults born in 1958, who participated in higher education (HE) in a context where most people from the same socio-economic backgrounds did not. Drawing on Bourdieu’s social theory, the findings suggest that different types of retrospective accounts were mobilised to reconcile working class habitus of origin and the perceived habitus as adults. Most research on working class and higher education focuses on the experiences of youth. By contrast, the use of retrospective accounts of adults has enabled the study to capture the implications that the educational trajectories have later in life. The authors consider these accounts a part of wider narratives that they define ‘therapeutic’. Therapeutic narratives were employed to come to terms with the ambivalence produced by social mobility. Therefore, respondents were negotiating the sense of exclusion attached to class change, and the acknowledgement of the opportunities associated with a working class habitus accessing new social fields viaeducation

Trends in parent- and teacher-rated mental health problems among 10- and 11-year-olds in Great Britain: 1999-2012

BACKGROUND: Previous evidence indicates that mental health problems are becoming more common for adolescents. Less is known about whether these trends have continued and there has been no study to date which has specifically focused on early adolescents over a sufficiently long period. This study examines changes in parent- and teacher-reported mental health problems among 10- and 11-year-olds in 1999, 2004 and 2012 in Great Britain. METHODS: Parent and teacher ratings of the Strengths and Difficulties Questionnaire were used to compare the prevalence of conduct problems, hyperactivity/inattention, emotional problems, peer problems and total difficulties among 10- and 11-year-olds in three nationally representative British samples assessed in 1999 (n = 1904), 2004 (n = 1348) and 2012 (n = 11,397). RESULTS: Teacher reports showed improving trends for boys' and girls' mental health from 1999 to 2012, particularly for externalizing behaviours (i.e. conduct problems and hyperactivity/inattention). Parent reports, on the other hand, identified only one area of sustained improvement between 1999 and 2012, namely hyperactivity/inattention among boys. Although parent reports of girls' mental health indicate improving trends from 1999 to 2004, they also suggest worsening mental health from 2004. CONCLUSIONS: These findings suggest that perceptions of emotional and behavioural problems vary by the gender of the adolescent, the context in which they are observed or by whom they are reported

Gender-Specific Trajectories of Conduct Problems from Ages 3 to 11

Gender-specific pathways of conduct problems (CP) from toddlerhood have received little attention. Using a nationally representative sample of UK children born in 2000-2001 (6458 boys and 6340 girls), the current study (a) identified subgroups of CP pathways separately for boys and girls from ages 3 to 11 and (b) examined early precursors (pregnancy to 9 months) of these trajectories. Group-based trajectory models identified four distinct trajectories for both boys and girls: each characterized as 'low'; 'early-onset, desisting'; 'early-onset, persistent' and 'school-onset'. This suggests that the taxonomic framework developed to conceptualise childhood-onset CP among males is also applicable to females, though needing some revision to capture heterogeneity identified during early and middle childhood. We also found significant precursors of the different trajectory groups with some variation by gender. Early socioeconomic deprivation was a significant risk factor of the early-onset pathways among both genders, but played no significant role for 'school-onset'. Childhood-onset trajectories of boys, but not girls, were predicted by parenting attitudes and behaviour

Trust in Private and Common Property Experiments

We report the results from a series of experiments designed to investigate behavior in two settings that are frequently posited in the policy literature as generating different outcomes: private property and common property. The experimental settings closely parallel earlier experimental studies of the investment or trust game. The primary research question relates to the effect of the initial allocation of property rights on the level of trust that subjects will extend to others with whom they are linked. We find that assigning the initial endowments as common property of each of N pairs of a first mover and second mover leads to marginally greater cooperation or trust than when the initial endowments are fully owned by the two individual movers as their, respective, private property. Subjectsâ?? decisions are also shown to be correlated with attitudes toward trust and fairness that are measured in post-experiment questionnaires.

UTLS temperature validation of MPI-ESM decadal hindcast experiments with GPS radio occultations

Global Positioning System (GPS) radio occultation (RO) temperature data are used to validate MPI-ESM (Max Planck Institute – Earth System Model) decadal hindcast experiments in the upper troposphere and lower stratosphere (UTLS) region between 300 hPa and 10 hPa (8 km and 32 km) for the time period between 2002 and 2011. The GPSRO dataset is unique since it is very precise, calibration independent and covers the globe better than the usual radiosonde dataset. In addition it is vertically finer resolved than any of the existing satellite temperature measurements available for the UTLS and provides now a unique one decade long temperature validation dataset. The initialization of the MPI-ESM decadal hindcast runs mostly increases the skill of the atmospheric temperatures when compared to uninitialized climate projections with very high skill scores for lead-year one, and gradually decreases for the later lead-years. A comparison between two different initialization sets (b0, b1) of the low-resolution (LR) MPI-ESM shows increased skills in b1-LR in most parts of the UTLS in particular in the tropics. The medium resolution (MR) MPI-ESM initializations are characterized by reduced temperature biases in the uninitialized runs as compared to observations and a better capturing of the high latitude northern hemisphere interannual polar vortex variability as compared to the LR model version. Negative skills are found for the b1-MR hindcasts however in the regions around the mid-latitude tropospheric jets on both hemispheres and in the vicinity of the tropical tropopause in comparison to the b1-LR variant. It is interesting to highlight that none of the model experiments can reproduce the observed positive temperature trend in the tropical tropopause region since 2001 as seen by GPSRO data

Initial and sustained brain responses to contextual conditioned anxiety in humans

AbstractContextual fear conditioning takes place if the occurrence of threat cannot be predicted by specific cues. As a consequence the context becomes the best predictor of the threat and later induces anxiety (sustained fear response). Previous studies suggest that both the amygdala and the hippocampus are crucial for contextual fear conditioning. First, we wanted to further elucidate the neuronal correlates of long-lasting contextual threat within a highly ecologically setting created in virtual reality (VR). Second, we wanted to distinguish between initial and sustained components of the anxiety response to a threatening situation. Twenty-four participants were guided through two virtual offices for 30s each. They received unpredictable electric stimuli (unconditioned stimulus, US) in one office (anxiety context, CXT+), but never in the second office (safety context, CXT−). Successful contextual fear conditioning was indexed by higher anxiety and enhanced US-expectancy ratings for CXT+ versus CXT−. Initial neural activity was assessed by modeling the onsets of both contexts, and sustained neural activity by considering the entire context duration (contrasts: CXT+ > CXT−). Amygdala and hippocampus revealed sustained activity. Initial and sustained activities were found in the middle temporal gyrus, and primary motor cortex (M1). Additional initial activity was obvious in orbitofrontal (OFC), dorsomedial (dmPFC), and dorsolateral prefrontal cortex (dlPFC). These results suggest that entering a threatening context initially induces conditioned fear reactions (M1), recall of contingency awareness (dlPFC), and explicit threat appraisal (dmPFC, OFC). While remaining in the threatening context might involve anxiety-like conditioned responses (amygdala, M1) and the generation of a spatial map to predict where and when a threatening event may occur (hippocampus). We conclude that in humans initial versus sustained anxiety responses triggered by a threat associated context are associated with distinguishable brain activation patterns involving a fear network and a “contingency-cognitive” network, respectively

De vererving van het witrikpatroon en de variatie daaarin

In een afstudeeropdracht voor van Hall Larenstein is de vererving van de witrikkleur bij runderen bestudeerd en is de vraag beantwoord waarom er zoveel kleurpatronen zijn binnen deze kleurslag