On the Andreadakis-Johnson filtration of the automorphism group of a free group

The Johnson filtration of the automorphism group of a free group is composed of those automorphisms which act trivially on nilpotent quotients of the free group. We compute cohomology classes as follows: (i) we analyze analogous classes for a subgroup of the pure symmetric automorphism group of a free group, and (ii) we analyze features of these classes which are preserved by the Johnson homomorphism. One consequence is that the ranks of the cohomology groups in any fixed dimension between 1 and n-1 increase without bound for terms deep in the Johnson filtraton.Comment: Corrections; revisions to proof of main theore

Public and Private Institutional Responses to Advocacy Attacks: The Case of the Global Cocoa Industry and Child Labour Abuse

Over the past decade the global agri-food industry has come under increasing attack by advocacy groups related to their production and marketing processes (Bowmar and Gow, 2009). Advocacy groups have used these attacks to exploit the growing intergenerational disconnect between consumers and farming to campaign for narrowly defined political ideals while challenging traditional agricultural practices (Olin, 1999). This disconnect has provided advocacy groups the opportunity to use boycotts and other media attacks to severely adverse impact not only branded manufacturers and retailers, but their farmer suppliers. The agri-food industry’s challenge is to understand how to develop appropriate individual and collective responses to these attacks that minimize their current and future adverse impact and provide mutually beneficial outcomes for all of the channel members. Using an instrumental case study of the international cocoa and chocolate industry’s response to the child labour abuse and trafficking claims, we analyse and evaluate the alternative individual and collective responses that firms can implement to minimize their current and future adverse impact from advocacy attacks and provide mutually beneficial outcomes for all of the channel members. This paper follows a comparative institutional analysis methodology to analyse the multiple nested case studies and evaluate the impact and implications of each alternative.Certification, Advocacy, Cocoa, Chocolate, Agribusiness, Agricultural and Food Policy, Community/Rural/Urban Development, Environmental Economics and Policy, International Development, Marketing,

The Anaphase-Promoting Complex (APC) ubiquitin ligase affects chemosensory behavior in \u3cem\u3eC. elegans\u3c/em\u3e

The regulation of fundamental aspects of neurobiological function has been linked to the ubiquitin signaling system (USS), which regulates the degradation and activity of proteins and is catalyzed by E1, E2, and E3 enzymes. The Anaphase-Promoting Complex (APC) is a multi-subunit E3 ubiquitin ligase that controls diverse developmental and signaling processes in post-mitotic neurons; however, potential roles for the APC in sensory function have yet to be explored. In this study, we examined the effect of the APC ubiquitin ligase on chemosensation in Caenorhabditis elegans by testing chemotaxis to the volatile odorants, diacetyl, pyrazine, and isoamyl alcohol, to which wild-type worms are attracted. Animals with loss of function mutations in either of two alleles (g48 and ye143) of the gene encoding the APC subunit EMB-27 APC6 showed increased chemotaxis towards diacetyl and pyrazine, odorants sensed by AWA neurons, but exhibited normal chemotaxis to isoamyl alcohol, which is sensed by AWC neurons. The statistically significant increase in chemotaxis in the emb-27 APC6 mutants suggests that the APC inhibits AWA-mediated chemosensation in C. elegans. Increased chemotaxis to pyrazine was also seen with mutants lacking another essential APC subunit, MAT-2 APC1; however, mat-2 APC1 mutants exhibited wild type responses to diacetyl. The difference in responsiveness of these two APC subunit mutants may be due to differential strength of these hypomorphic alleles or may indicate the presence of functional sub-complexes of the APC at work in this process. These findings are the first evidence for APC-mediated regulation of chemosensation and lay the groundwork for further studies aimed at identifying the expression levels, function, and targets of the APC in specific sensory neurons. Because of the similarity between human and C. elegans nervous systems, the role of the APC in sensory neurons may also advance our understanding of human sensory function and disease

Kunsia tomentosus (Rodentia: Cricetidae)

Kunsia tomentosus (Lichtenstein, 1830), the woolly giant rat, is a semifossorial cricetid typically associated with the Cerrado and Beni domains in central South America. Kunsia was recently revised and includes only 1 species. It is the largest extant sigmondontine and is readily distinguishable by its size, a body covered with dark-gray fur that is coarse and dense, moderately short tail, short limbs, bicolored manus and pes, and long, powerful claws. It inhabits primarily open grasslands and savannas from central and southwestern Brazil and northern Bolivia. K. tomentosus presently is not considered threatened; however, westernmost populations have presumably been extirpated in the past 2 centuries.Fil: Bezerra, Alexandra M. R.. Universidade do Brasília; Brasil. Escola Nacional de Saude Publica Sergio Arouca. Fundación Oswaldo Cruz; BrasilFil: Pardiñas, Ulises Francisco J.. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Centro Nacional Patagónico. Instituto de Diversidad y Evolución Austral; Argentin

Seasonal dynamics of soil respiration and nitrogen mineralization in chronically warmed and fertilized soils

Although numerous studies have examined the individual effects of increased temperatures and N deposition on soil biogeochemical cycling, few have considered how these disturbances interact to impact soil C and N dynamics. Likewise, many have not assessed season-specific responses to warming and N inputs despite seasonal variability in soil processes. We studied interactions among season, warming, and N additions on soil respiration and N mineralization at the Soil Warming × Nitrogen Addition Study at the Harvard Forest. Of particular interest were wintertime fluxes of C and N typically excluded from investigations of soils and global change. Soils were warmed to 5°C above ambient, and N was applied at a rate of 5 g m−2 y−1. Soil respiration and N mineralization were sampled over two years between 2007 and 2009 and showed strong seasonal patterns that mirrored changes in soil temperature. Winter fluxes of C and N contributed between 2 and 17% to the total annual flux. Net N mineralization increased in response to the experimental manipulations across all seasons, and was 8% higher in fertilized plots and 83% higher in warmed plots over the duration of the study. Soil respiration showed a more season-specific response. Nitrogen additions enhanced soil respiration by 14%, but this increase was significant only in summer and fall. Likewise, warming increased soil respiration by 44% over the whole study period, but the effect of warming was most pronounced in spring and fall. The only interaction between warming × N additions took place in autumn, when N availability likely diminished the positive effect of warming on soil respiration. Our results suggest that winter measurements of C and N are necessary to accurately describe winter biogeochemical processes. In addition, season-specific responses to the experimental treatments suggest that some components of the belowground community may be more susceptible to warming and N additions than others. Seasonal changes in the abiotic environment may have also interacted with the experimental manipulations to evoke biogeochemical responses at certain times of year

Physicians' perspectives on the treatment of patients with eating disorders in the acute setting

Abstract Background Hospitalisation for an eating disorder is rare, however treatment in the acute medical setting can be a life-saving admission. While the multidisciplinary team delivers overall patient care, medical decisions are the responsibility of the treating physicians. Treatment decisions directly impact on patient care and outcomes. This study aimed to explore the considerations that influence the medical decisions of physicians when treating patients with eating disorders in the acute setting. Method Semi-structured interviews were conducted with ten medical physicians who had previously treated eating disorders on a general medical unit in two Australian tertiary hospitals. An interview schedule, based on the literature and four relevant domains from the Consolidated Framework for Implementation Research, was developed. Interviews were audio recorded, transcribed verbatim and analyzed thematically. Coding and interim themes and sub-themes were developed by two dietitian researchers; these were further refined through researcher discussion and triangulation with two additional dietitian researchers. Results Ten doctors were interviewed (3 consultants (1 adult general medical and 2 paediatricians: 13–16 years medical experience), 2 registrars (4–7 years experience), 1 resident (1 year experience), and 4 interns (< 1 year experience). Doctors described memorable patient cases, related to hospital stays over several weeks. Interviews ranged in length from 58 min to 91 min. Four themes (with five sub-themes) were developed: 1) navigating uncertainty (focusing on processes and goals and seeking information), 2) being “the good doctor” (doing the right thing), 3) seeing the big picture (depending on key players and considering short and long-term), and 4) involving family and patient. Conclusions Non-specialist physicians described challenges in the treatment of eating disorders in the inpatient setting. They take a holistic approach that considers both short and longer-term goals, relying on specialist colleagues, the wider multidisciplinary team and sometimes family members to guide treatment decisions during admissions on general medical wards. Additional support, education and training centered on the key themes may increase physicians’ confidence and ability to make effective treatment decisions for this patient group. The results are relevant to all health professionals working in this field to better understand the priorities of medical physicians and to support them to achieve positive outcomes in the inpatient treatment of patients with eating disorders

Examining the Effects of AAC Intervention on Oral Language in Children with Autism Spectrum Disorders: A Systematic Review

This systematic review researched the efficacy of augmentative and alternative communication (AAC) in increasing oral communication in children with Autism Spectrum Disorder (ASD). It may be used to inform best practice when working with children with ASD. The search strategy reviewed medical, social science, and communication databases. Inclusionary criteria consisted of peer-reviewed, quantitative research published after 2007 regarding children with ASD under age 18. The included studies used AAC interventions and measured spoken language outcomes. After conducting an initial database search with these criteria, a manual search was performed using references from the found articles. Results varied across studies. Although the trend demonstrates increases in verbal language with AAC intervention, few studies show statistically significant outcomes. The studies indicate that additional factors, such as verbal communication at baseline, may affect outcomes. AAC use did not decrease verbal language. Limitations included few randomized control trial designs, few study replications, and varied outcome measures. Based on the studies analyzed, implementation of AAC may increase the number of communicative acts, but may not reliably increase verbal language. Further research is needed to understand the most effective implementation of AAC intervention to increase verbal language. Higher quality research in the form of randomized control trials, and the replication of studies to confirm results is necessary to inform evidence-based practice. The findings are consistent with those of previous systematic reviews and meta analyses. Future considerations should include type of AAC, communicative act being measured, longitudinal studies, and increased use of formal measures.https://scholarworks.uvm.edu/csdms/1002/thumbnail.jp