The genesis of cerebellar interneurons and the prevention of neural DNA damage require XRCC1

Defective responses to DNA single strand breaks underlie various neurodegenerative diseases. However, the exact role of this repair pathway during the development and maintenance of the nervous system is unclear. Using murine neural-specific inactivation of Xrcc1, a factor that is critical for the repair of DNA single strand breaks, we found a profound neuropathology that is characterized by the loss of cerebellar interneurons. This cell loss was linked to p53-dependent cell cycle arrest and occurred as interneuron progenitors commenced differentiation. Loss of Xrcc1 also led to the persistence of DNA strand breaks throughout the nervous system and abnormal hippocampal function. Collectively, these data detail the in vivo link between DNA single strand break repair and neurogenesis and highlight the diverse consequences of specific types of genotoxic stress in the nervous system

Tracing the origins of rescued chimpanzees reveals widespread chimpanzee hunting in Cameroon

<p>Abstract</p> <p>Background</p> <p>While wild chimpanzees are experiencing drastic population declines, their numbers at African rescue and rehabilitation projects are growing rapidly. Chimpanzees follow complex routes to these refuges; and their geographic origins are often unclear. Identifying areas where hunting occurs can help law enforcement authorities focus scarce resources for wildlife protection planning. Efficiently focusing these resources is particularly important in Cameroon because this country is a key transportation waypoint for international wildlife crime syndicates. Furthermore, Cameroon is home to two chimpanzee subspecies, which makes ascertaining the origins of these chimpanzees important for reintroduction planning and for scientific investigations involving these chimpanzees.</p> <p>Results</p> <p>We estimated geographic origins of 46 chimpanzees from the Limbe Wildlife Centre (LWC) in Cameroon. Using Bayesian approximation methods, we determined their origins using mtDNA sequences and microsatellite (STRP) genotypes compared to a spatial map of georeferenced chimpanzee samples from 10 locations spanning Cameroon and Nigeria. The LWC chimpanzees come from multiple regions of Cameroon or forested areas straddling the Cameroon-Nigeria border. The LWC chimpanzees were partitioned further as originating from one of three biogeographically important zones occurring in Cameroon, but we were unable to refine these origin estimates to more specific areas within these three zones.</p> <p>Conclusions</p> <p>Our findings suggest that chimpanzee hunting is widespread across Cameroon. Live animal smuggling appears to occur locally within Cameroon, despite the existence of local wildlife cartels that operate internationally. This pattern varies from the illegal wildlife trade patterns observed in other commercially valuable species, such as elephants, where specific populations are targeted for exploitation. A broader sample of rescued chimpanzees compared against a more comprehensive grid of georeferenced samples may reveal 'hotspots' of chimpanzee hunting and live animal transport routes in Cameroon. These results illustrate also that clarifying the origins of refuge chimpanzees is an important tool for designing reintroduction programs. Finally, chimpanzees at refuges are frequently used in scientific investigations, such as studies investigating the history of zoonotic diseases. Our results provide important new information for interpreting these studies within a precise geographical framework.</p

The predicament of primary physical education: a consequence of 'insufficient' ITT and 'ineffective' CPD?

Background: Research on primary physical education (PE) in England and other countries has shown that it is an aspect of the curriculum that has suffered from sparse initial teacher training (ITT). As a consequence of ‘insufficient’ time spent on PE in ITT (PE-ITT), primary teachers often have low levels of confidence and competence with respect to teaching the subject. Evidence also points to inadequacies in traditional forms of professional development in PE (PE-CPD), leading to calls for more effective ways of developing teachers' competence to deliver high quality PE. Purpose: To explore primary school teachers' experiences of PE during ITT and the PE context in their schools prior to them engaging in a national PE-CPD programme, and their perceptions of the immediate and longer-term effects of this programme. Setting and participants: Primary school teachers in five local education authorities in England. Research design and data collection: A combination of quantitative and qualitative methodological approaches were adopted, including: pre-course audits, course evaluations, focus groups and semi-structured interviews. The pre-course audits captured information about the teachers' experiences of PE-ITT and the PE context in their schools prior to them engaging in the CPD. The course evaluations focused on initial impressions of the PE-CPD, and the focus groups and interviews captured the teachers' perceptions of its longer-term effects. Findings: For up to half of the teachers, their PE-ITT was ‘insufficient’ in terms of the time dedicated to it and the breadth of coverage of the subject. The PE-CPD programme, which was designed in the light of ‘insufficient’ PE-ITT, demonstrated features of ‘effective’ CPD in that it was considered relevant to classroom practice and partially addressed some of their many needs (especially in relation to content ideas and inclusive practice). However, its effectiveness was undoubtedly limited due to: its short time span and minimal engagement with teachers; a heavy reliance on resources; and the absence of follow-up support. In addition, it did not adequately address known areas of development for primary PE (such as medium to long-term planning and assessment) and was challenged in meeting the diverse needs of primary teachers of 5–11 year olds. Furthermore, inadequate PE time and reduced opportunities to teach PE in some schools limited implementation of learning from the PE-CPD. Conclusions: The findings of this study confirmed that PE-ITT continues to be ‘insufficient’ for many primary teachers and that the PE-CPD in question, whilst partially ‘effective’, was not, and could never have been, the panacea for the inherent issues within and predicament of primary PE. In effect, this PE-CPD programme with its limited duration and engagement with teachers, a heavy reliance on resources, and no planned follow-up support was not sufficiently different to forms of CPD described in the literature as ‘ineffective’; consequently, it could not hope to compensate for long-term systemic weaknesses such as inadequate primary PE-ITT. These weaknesses need to be addressed through a dual approach of ‘sufficient’ PE-ITT followed by ‘effective’ PE-CPD which engages teachers and their colleagues in long-term collaborative endeavours that support transformative practice

Hard-Object Feeding in Sooty Mangabeys (Cercocebus atys) and Interpretation of Early Hominin Feeding Ecology

Morphology of the dentofacial complex of early hominins has figured prominently in the inference of their dietary adaptations. Recent theoretical analysis of craniofacial morphology of Australopithecus africanus proposes that skull form in this taxon represents adaptation to feeding on large, hard objects. A modern analog for this specific dietary specialization is provided by the West African sooty mangabey, Cercocebus atys. This species habitually feeds on the large, exceptionally hard nuts of Sacoglottis gabonensis, stereotypically crushing the seed casings using their premolars and molars. This type of behavior has been inferred for A. africanus based on mathematical stress analysis and aspects of dental wear and morphology. While postcanine megadontia, premolar enlargement and thick molar enamel characterize both A. africanus and C. atys, these features are not universally associated with durophagy among living anthropoids. Occlusal microwear analysis reveals complex microwear textures in C. atys unlike those observed in A. africanus, but more closely resembling textures observed in Paranthropus robustus. Since sooty mangabeys process hard objects in a manner similar to that proposed for A. africanus, yet do so without the craniofacial buttressing characteristic of this hominin, it follows that derived features of the australopith skull are sufficient but not necessary for the consumption of large, hard objects. The adaptive significance of australopith craniofacial morphology may instead be related to the toughness, rather than the hardness, of ingested foods

An Individual-Oriented Model on the Emergence of Support in Fights, Its Reciprocation and Exchange

Complex social behaviour of primates has usually been attributed to the operation of complex cognition. Recently, models have shown that constraints imposed by the socio-spatial structuring of individuals in a group may result in an unexpectedly high number of patterns of complex social behaviour, resembling the dominance styles of egalitarian and despotic species of macaques and the differences between them. This includes affiliative patterns, such as reciprocation of grooming, grooming up the hierarchy, and reconciliation. In the present study, we show that the distribution of support in fights, which is the social behaviour that is potentially most sophisticated in terms of cognitive processes, may emerge in the same way. The model represents the spatial grouping of individuals and their social behaviour, such as their avoidance of risks during attacks, the self-reinforcing effects of winning and losing their fights, their tendency to join in fights of others that are close by (social facilitation), their tendency to groom when they are anxious, the reduction of their anxiety by grooming, and the increase of anxiety when involved in aggression. Further, we represent the difference in intensity of aggression apparent in egalitarian and despotic macaques. The model reproduces many aspects of support in fights, such as its different types, namely, conservative, bridging and revolutionary, patterns of choice of coalition partners attributed to triadic awareness, those of reciprocation of support and ‘spiteful acts’ and of exchange between support and grooming. This work is important because it suggests that behaviour that seems to result from sophisticated cognition may be a side-effect of spatial structure and dominance interactions and it shows that partial correlations fail to completely omit these effects of spatial structure. Further, the model is falsifiable, since it results in many patterns that can easily be tested in real primates by means of existing data

Strengthening ‘the foundations’ of the primary school curriculum

This is an Accepted Manuscript of an article published by Taylor & Francis in Education 3-13 on 21 May 2016, available online: http://www.tandfonline.com/10.1080/03004279.2016.1185137.The low status of the foundation subjects (e.g. Music and Physical Education (PE)) in English primary schools is well documented. Using PE as an illustrative example, a thematic analysis of 51 PE trainee students’ assignments, based on their perceptions of a two-week experience in a primary school, highlighted a number of areas of concern (e.g. limited/inadequate preparation; insufficient teacher knowledge/confidence; variable/limited subject leadership and non-qualified teachers delivering the curriculum). The possibility of teachers, coaches and other external specialists learning collaboratively with and from each other within a community of practice/learning is proposed as one way of strengthening the foundation subjects within the primary school curriculum

Do facial gestures, visibility or speed of movement influence gaze following responses in pigtail macaques?

A. Paukner e J.R. Anderson sono affiliati a: Department of Psychology, University of Stirling, Stirling FK9 4LA, U