Signed permutohedra, delta-matroids, and beyond

We establish a connection between the algebraic geometry of the type B permutohedral toric variety and the combinatorics of delta-matroids. Using this connection, we compute the volume and lattice point counts of type B generalized permutohedra. Applying tropical Hodge theory to a new framework of "tautological classes of delta-matroids," modeled after certain vector bundles associated to realizable delta-matroids, we establish the log-concavity of a Tutte-like invariant for a broad family of delta-matroids that includes all realizable delta-matroids. Our results include new log-concavity statements for all (ordinary) matroids as special cases

Validity of self-assessment of hallux valgus using the Manchester scale

<p>Abstract</p> <p>Background</p> <p>Hallux valgus (HV) is a common condition involving the progressive subluxation of the first metatarsophalangeal joint due to lateral deviation of the hallux and medial deviation of the first metatarsal. The objective of this study was to evaluate the re-test reliability and validity of self-assessment of HV using a simple clinical screening tool involving four standardised photographs (the Manchester scale), in order to determine whether this tool could be used for postal surveys of the condition.</p> <p>Methods</p> <p>HV was assessed with the Manchester scale in 138 people aged 65 to 93 years of age (102 women and 36 men) as part of a larger randomised controlled trial. At the six month follow-up assessment, HV was reassessed to determine re-test reliability, and participants were asked to self-assess their degree of HV independent of the examiners. Associations between (i) baseline and follow-up assessments of the examiners and (ii) participant and examiner assessments were performed using weighted kappa statistics. Analyses were then repeated after HV was dichotomised as present or absent using unweighted kappa, and sensitivity and specificity of self-assessment of HV was determined.</p> <p>Results</p> <p>Re-test reliability of the examiners was substantial to almost perfect (weighted kappa = 0.78 to 0.90), and there was a substantial level of agreement between observations of the participants and the examiners (weighted kappa = 0.71 to 0.80). Overall, there was a slight tendency for participants to rate their HV as less severe than the examiners. When the Manchester scale scores were dichotomised, agreement was substantial to almost perfect for both re-test comparisons (kappa = 0.80 to 0.89) and substantial for comparisons between participants and examiners (kappa = 0.64 to 0.76). The sensitivity and specificity of self-assessment of HV using the dichotomous scale were 85 and 88%, respectively.</p> <p>Conclusions</p> <p>The Manchester scale demonstrates high re-test reliability, and self-assessment scores obtained by participants are strongly associated with scores obtained by examiners. These findings indicate that the tool can be used with confidence in postal surveys to document the presence and severity of HV.</p> <p>Trial registration</p> <p>ACTRN12608000065392</p

Olhar o cotidiano: percursos para uma psicologia social do trabalho

Resumo: O artigo esboça os percursos de pesquisas que têm levado a psicologia social do trabalho ao estudo do cotidiano laboral. Apresenta o cotidiano como campo de apreensão do real, partindo de uma discussão interdisciplinar sobre o tema, salientando seus aspectos de repetição e de ruptura e as relações entre dimensões micro e macrossociais. Localiza os esforços de constituir o cotidiano como objeto da psicologia social e aponta para as dificuldades de teorização desse objeto. Finalmente, discute as razões do reconhecimento do cotidiano como campo privilegiado de investigação para o projeto de uma psicologia social do trabalho, na medida em que favorece o reconhecimento das singularidades dos sentidos e dos significados construídos pelos trabalhadores, das formas de interação social, dos processos organizativos, da micropolítica, das práticas astuciosas construídas no interior de relações assimétricas de poder

Reviewing, indicating, and counting books for modern research evaluation systems

In this chapter, we focus on the specialists who have helped to improve the conditions for book assessments in research evaluation exercises, with empirically based data and insights supporting their greater integration. Our review highlights the research carried out by four types of expert communities, referred to as the monitors, the subject classifiers, the indexers and the indicator constructionists. Many challenges lie ahead for scholars affiliated with these communities, particularly the latter three. By acknowledging their unique, yet interrelated roles, we show where the greatest potential is for both quantitative and qualitative indicator advancements in book-inclusive evaluation systems.Comment: Forthcoming in Glanzel, W., Moed, H.F., Schmoch U., Thelwall, M. (2018). Springer Handbook of Science and Technology Indicators. Springer Some corrections made in subsection 'Publisher prestige or quality

Organizações sociais e agroecologia: construção de identidades e transformações sociais.

No presente trabalho, procuramos discutir as transformações ocorridas no espaço da agricultura familiar pós-Revolução Verde, especialmente a partir do movimento contestatório engendrado por organizações sociais que defendem o ideário agroecológico. Inicialmente, procurou-se compreender como a identidade a e realidade social são construídas e reconstruídas socialmente. Utilizou-se uma abordagem fenomenológica para investigar como se dá a ruptura com a realidade convencional e a transição para a agroecologia. Com base nas evidências empíricas, é possível dizer que a agroecologia participa da ressignificação positiva da identidade social dos agricultores. Entretanto, o reconhecimento da nova identidade passa pelo questionamento da realidade dominante a partir de crises vividas pelos agricultores. Sua manutenção requer partilhá-la intersubjetivamente com um grupo ou organização