Quivers of monoids with basic algebras

We compute the quiver of any monoid that has a basic algebra over an algebraically closed field of characteristic zero. More generally, we reduce the computation of the quiver over a splitting field of a class of monoids that we term rectangular monoids (in the semigroup theory literature the class is known as $\mathbf{DO}$) to representation theoretic computations for group algebras of maximal subgroups. Hence in good characteristic for the maximal subgroups, this gives an essentially complete computation. Since groups are examples of rectangular monoids, we cannot hope to do better than this. For the subclass of $\mathscr R$-trivial monoids, we also provide a semigroup theoretic description of the projective indecomposables and compute the Cartan matrix.Comment: Minor corrections and improvements to exposition were made. Some theorem statements were simplified. Also we made a language change. Several of our results are more naturally expressed using the language of Karoubi envelopes and irreducible morphisms. There are no substantial changes in actual result

Relato de experi?ncia profissional em desenvolvimento Front-End na Commarket

Este trabalho carrega a finalidade de relatar as experi?ncias profissionais do discente do curso de An?lise e Desenvolvimento de Sistemas do Instituto Federal da Para?ba, vivenciadas no est?gio oferecido pela empresa Commarket na modalidade Home Office. Dentre as atividades prestadas, o referente atuou principalmente no setor de desenvolvimento front-end, sendo este o setor onde o mesmo descobriu seu foco de carreira por possuir mais afinidade no que a ?rea se refere. Traduzir os prot?tipos gr?ficos de interface em alta fidelidade de diversos produtos em sites e aplicativos, bem como fazer integra??es com APIs para fornecer comunica??o a estes, fazia (e faz) parte da rotina di?ria do autor

Modelling is for reasoning

In a broad sense, computing is an area of knowledge from which a popular and effective technology emerged long before a solid, specific, scientific methodology, let alone formal foundations, had been put forward. This might explain some of the weaknesses in the software industry, on the one hand, as well as an excessively technology-oriented view which dominates computer science training at pre-university and even undergraduate teaching, on the other. Modelling, understood as the ability to choose the right abstractions for a problem domain, is consensually recognised as essential for the development of true engineering skills in this area, as it is in all other engineering disciplines. But, how can the basic problem-solving strategy, one gets used to from school physics: understand the problem, build a mathematical model, reason within the model, calculate a solution, be taken (and taught) as the standard way of dealing with software design problems? This paper addresses this question, illustrating and discussing the interplay between modelling and reasoning.(undefined

Violência escolar: produções de sentidos midiatizados

School violence: mediated senses productionsResumoEste artigo discute, a partir de pesquisas realizadas na cidade de Mossoró, no estado do Rio Grande do Norte, a influência da mídia na construção do significado do termo violência escolar. Buscamos entender como as matérias publicadas em blogs e jornais contribuem para a construção do significante ‘violência escolar’. Partimos do princípio que o preenchimento do conceito é feito de forma provisória, discursiva e interessada, envolvendo diversas demandas de combate a violência que circula na sociedade e são ampliadas/divulgadas pela imprensa. Compreendemos, assim, a impossibilidade de fixação de sentidos únicos de violência escolar. Consideramos ainda, que qualquer atitude nesse sentido será contingencial, contextual e temporária. Desse modo, a sociedade e a própria escola constroem seus conceitos em um processo complexo de significação em diálogo com o contexto, surgindo várias possibilidades de compreensão do fenômeno, sendo a mídia um dos elementos orientadores da construção dos sentidos de violência escolar.Palavras-chave: violência; escola; significados; mídia Abstract: This article discusses, from research conducted in the city of Mossoró, in the state of Rio Grande do Norte, the influence of the media in constructing the meaning of the term school violence. We seek to understand how the articles published in blogs and newspapers contribute to the construction of significant school violence. As a construction we understand the meaning of the term 'school violence'. We assume that this filling is done in a provisional, discursive and interested way. We also consider that any attitude in this sense will be contingent and temporary. We understand that society and the school itself construct their concepts in a complex process of meaning in dialogue with the context, arising several possibilities of understanding the phenomenon of school violence, being the media one of the guiding elements of construction of the meanings of school violence.Keywords: violence in school; meanings; media  

Equivariant cohomology over Lie groupoids and Lie-Rinehart algebras

Using the language and terminology of relative homological algebra, in particular that of derived functors, we introduce equivariant cohomology over a general Lie-Rinehart algebra and equivariant de Rham cohomology over a locally trivial Lie groupoid in terms of suitably defined monads (also known as triples) and the associated standard constructions. This extends a characterization of equivariant de Rham cohomology in terms of derived functors developed earlier for the special case where the Lie groupoid is an ordinary Lie group, viewed as a Lie groupoid with a single object; in that theory over a Lie group, the ordinary Bott-Dupont-Shulman-Stasheff complex arises as an a posteriori object. We prove that, given a locally trivial Lie groupoid G and a smooth G-manifold f over the space B of objects of G, the resulting G-equivariant de Rham theory of f boils down to the ordinary equivariant de Rham theory of a vertex manifold relative to the corresponding vertex group, for any vertex in the space B of objects of G; this implies that the equivariant de Rham cohomology introduced here coincides with the stack de Rham cohomology of the associated transformation groupoid whence this stack de Rham cohomology can be characterized as a relative derived functor. We introduce a notion of cone on a Lie-Rinehart algebra and in particular that of cone on a Lie algebroid. This cone is an indispensable tool for the description of the requisite monads.Comment: 47 page

Broad diversity of fungi in Hospital Water

Introduction. Some studies have reported the occurrence of microorganisms isolated from water. Considering these microorganisms, fungi are known to occur ubiquitously in the environment, including water, and some are pathogenic and may cause health problems, especially in immunocompromised individuals. The aim of this study was to identify fungi in hospital water samples and to correlate their presence with the concentration of free residual chlorine. Methods. Water samples (100 mL) were collected from taps (n = 74) and water purifiers (n = 14) in different locations in a university hospital. Samples were filtered through a nitrocellulose membrane and placed on Sabouraud dextrose agar and incubated for 24 hours at 30°C. Fungi were identified according to established methods based on macroscopic and microscopic characteristics (filamentous) and physiological tests (yeasts). Free chlorine residual content was measured at the time of sample collection. Results. Seventy species of fungi were identified in the water samples and about 56% of the water samples contained culturable fungi. Cladosporium oxysporum, Penicillium spinulosum, and Aspergillus fumigatus were the most common filamentous fungi. Aureobasidium pullulans and Candida parapsilosis were the most common yeasts. Chemical analyses revealed that free residual chlorine was present in 81.8% of the samples within recommended concentrations. Among samples from water purifiers, 92.9% showed low levels of free residual chlorine (<0.2 mg/L). There was no significant association between chlorine concentrations (either within or outside the recommended range) and the presence of filamentous fungi and yeasts. Conclusions. This study showed that hospital water can be a reservoir for fungi, some of which are potentially harmful to immunocompromised patients. Free residual chlorine was ineffective in some samples.publishersversionpublishe

Irish women in the diaspora: exclusions and inclusions

Irish women have a long history of emigration which provides parallels with the experiences of women now moving to settle in Ireland. In both cases, women migrants have been needed to fill the massive deficit of paid domestic labor in rapidly industrialising economies. Over the last two centuries, these destinations for Irish women have included the USA, Britain and Australia, as well as Canada, New Zealand, South Africa and Argentina. Some of the complexities in the positioning of migrant Irish women within the “diaspora spaces” they occupy are explored in this article. I identify ongoing disadvantage for certain groups of Irish-born women, drawing on evidence primarily from Britain, which has the largest contemporary diasporic Irish population. Comparisons are made with Irish women's experiences in the USA and Australia, using Census and survey data generated by and for the 2002 Task Force on Policy regarding Emigrants. The concept of diaspora explicitly includes those identifying themselves as Irish over several generations. I use qualitative findings from the Irish 2 Project, a recent study of the large second-generation Irish population in Britain, to examine narratives of women living in Manchester who grew up in “Irish” households and are subsequently negotiating hybrid identities in adulthood. These offer insights into longitudinal dimensions of migrant experience and the continuing significance of ethnic difference

Evolving Gravitationally Unstable Disks Over Cosmic Time: Implications For Thick Disk Formation

Observations of disk galaxies at z~2 have demonstrated that turbulence driven by gravitational instability can dominate the energetics of the disk. We present a 1D simulation code, which we have made publicly available, that economically evolves these galaxies from z~2 to z~0 on a single CPU in a matter of minutes, tracking column density, metallicity, and velocity dispersions of gaseous and multiple stellar components. We include an H$_2$ regulated star formation law and the effects of stellar heating by transient spiral structure. We use this code to demonstrate a possible explanation for the existence of a thin and thick disk stellar population and the age-velocity dispersion correlation of stars in the solar neighborhood: the high velocity dispersion of gas in disks at z~2 decreases along with the cosmological accretion rate, while at lower redshift, the dynamically colder gas forms the low velocity dispersion stars of the thin disk.Comment: 18 pages, 6 figures, accepted for publication in ApJ. Code available at http://www.ucolick.org/~jforbes/gidget.htm

Comprehensive clinical and molecular analysis of 12 families with type 1 recessive cutis laxa.

Autosomal recessive cutis laxa type I (ARCL type I) is characterized by generalized cutis laxa with pulmonary emphysema and/or vascular complications. Rarely, mutations can be identified in FBLN4 or FBLN5. Recently, LTBP4 mutations have been implicated in a similar phenotype. Studying FBLN4, FBLN5, and LTBP4 in 12 families with ARCL type I, we found bi-allelic FBLN5 mutations in two probands, whereas nine probands harbored biallelic mutations in LTBP4. FBLN5 and LTBP4 mutations cause a very similar phenotype associated with severe pulmonary emphysema, in the absence of vascular tortuosity or aneurysms. Gastrointestinal and genitourinary tract involvement seems to be more severe in patients with LTBP4 mutations. Functional studies showed that most premature termination mutations in LTBP4 result in severely reduced mRNA and protein levels. This correlated with increased transforming growth factor-beta (TGFβ) activity. However, one mutation, c.4127dupC, escaped nonsense-mediated decay. The corresponding mutant protein (p.Arg1377Alafs(*) 27) showed reduced colocalization with fibronectin, leading to an abnormal morphology of microfibrils in fibroblast cultures, while retaining normal TGFβ activity. We conclude that LTBP4 mutations cause disease through both loss of function and gain of function mechanisms