On subreducts of subresiduated lattices and logic

Subresiduated lattices were introduced during the decade of 1970 by Epstein and Horn as an algebraic counterpart of some logics with strong implication previously studied by Lewy and Hacking. These logics are examples of subuintuitionistic logics, i.e., logics in the language of intuitionistic logic that are defined semantically by using Kripke models, in the same way as intuitionistic logic is defined, but without requiring of the models some of the properties required in the intuitionistic case. Also in relation with the study of subintuitionistic logics, Celani and Jansana get these algebras as the elements of a subvariety of that of weak Heyting algebras. Here, we study both the implicative and the implicative-infimum subreducts of subresiduated lattices. Besides, we propose a calculus whose algebraic semantics is given by these classes of algebras. Several expansions of this calculi are also studied together to some interesting properties of them

Geomorphological characteristics of mountain watershed rivers colonized by Castor canadensis in Tierra del Fuego, Argentina

Se estudió la geomorfología de una cuenca de montaña de los Andes Fueguinos colonizada por Castor canadensis, con el objeto de detectar los aspectos físicos de los ríos ocupados por esta especie introducida. Se aplicaron métodos cartográficos, de análisis geomorfológico, de análisis morfométrico de cuencas y de seguimiento de la colonización a lo largo del tiempo. Estos últimos se realizaron en la totalidad de la cuenca mediante muestreos en el terreno, aerofotogramétricos y aéreos en época otoñal. Los cursos colonizados por Castor canadensis se distribuyen uniformemente en la cuenca con distinto tipo de ocupación y de continuidad espacial. Hubo una mayor frecuencia de selección de los ríos de primer y segundo orden, y con gradiente de 0-6º. Los ríos de mayor orden son ocupados en sus cauces secundarios y estacionalmente. La margen norte de la cuenca tiene mayor desarrollo areal, mayor densidad de drenaje, mayor número de cursos de agua y, por lo tanto, ofrece mayores posibilidades de ocupación. Los ríos que drenan las unidades geomorfológicas denominadas “valles colgantes laterales” presentan mayor ocupación espacial que los ríos que drenan las unidades “frentes de ladera”. Los parámetros de selección de hábitat determinados en este estudio resultan semejantes a los hallados para esta especie en el Hemisferio Norte.The geomorphology of a Fuegian Andes watershed colonized by the introduced species Castor canadensis has been analyzed. The main objective was to distinguish the physical conditions of the occupied streams. Geomorphological analysis and mapping techniques were applied; also, colonization monitoring surveys in the entire watershed was made through terrestrial and aerophotogrametrical methods. Were made aerial surveys during the autumn. Streams of first and second order and low gradient (0-6º) were those chosen by Castor canadensis for settlement. The higher-order streams were seasonally occupied, but restricted only to their secondary landforms. The northern part of the watershed is larger in size, drainage density and stream numbers; therefore, it offers more settlement possibilities. The rivers of the lateral hanging valleys were more densely occupied than those of the slope units. Several of the conditions of rivers for Castor canadensis settlement observed in Tierra del Fuego were similar to those observed in the Northern Hemisphere

The writing on the wall: the concealed communities of the East Yorkshire horselads

This paper examines the graffiti found within late nineteenth and early-twentieth century farm buildings in the Wolds of East Yorkshire. It suggests that the graffiti were created by a group of young men at the bottom of the social hierarchy - the horselads – and was one of the ways in which they constructed a distinctive sense of communal identity, at a particular stage in their lives. Whilst it tells us much about changing agricultural regimes and social structures, it also informs us about experiences and attitudes often hidden from official histories and biographies. In this way, the graffiti are argued to inform our understanding, not only of a concealed community, but also about their hidden histor

Pituitary society guidance: pituitary disease management and patient care recommendations during the COVID-19 pandemic—an international perspective

Abstract: Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the viral strain that has caused the coronavirus disease 2019 (COVID-19) pandemic, has presented healthcare systems around the world with an unprecedented challenge. In locations with significant rates of viral transmission, social distancing measures and enforced ‘lockdowns’ are the new ‘norm’ as governments try to prevent healthcare services from being overwhelmed. However, with these measures have come important challenges for the delivery of existing services for other diseases and conditions. The clinical care of patients with pituitary disorders typically involves a multidisciplinary team, working in concert to deliver timely, often complex, disease investigation and management, including pituitary surgery. COVID-19 has brought about major disruption to such services, limiting access to care and opportunities for testing (both laboratory and radiological), and dramatically reducing the ability to safely undertake transsphenoidal surgery. In the absence of clinical trials to guide management of patients with pituitary disease during the COVID-19 pandemic, herein the Professional Education Committee of the Pituitary Society proposes guidance for continued safe management and care of this population

Involvement of the Efflux Pumps in Chloramphenicol Selected Strains of Burkholderia thailandensis: Proteomic and Mechanistic Evidence

Burkholderia is a bacterial genus comprising several pathogenic species, including two species highly pathogenic for humans, B. pseudomallei and B. mallei. B. thailandensis is a weakly pathogenic species closely related to both B. pseudomallei and B. mallei. It is used as a study model. These bacteria are able to exhibit multiple resistance mechanisms towards various families of antibiotics. By sequentially plating B. thailandensis wild type strains on chloramphenicol we obtained several resistant variants. This chloramphenicol-induced resistance was associated with resistance against structurally unrelated antibiotics including quinolones and tetracyclines. We functionally and proteomically demonstrate that this multidrug resistance phenotype, identified in chloramphenicol-resistant variants, is associated with the overexpression of two different efflux pumps. These efflux pumps are able to expel antibiotics from several families, including chloramphenicol, quinolones, tetracyclines, trimethoprim and some β-lactams, and present a partial susceptibility to efflux pump inhibitors. It is thus possible that Burkholderia species can develop such adaptive resistance mechanisms in response to antibiotic pressure resulting in emergence of multidrug resistant strains. Antibiotics known to easily induce overexpression of these efflux pumps should be used with discernment in the treatment of Burkholderia infections