Bioavailable iron in the Southern Ocean: the significance of the iceberg conveyor belt

Productivity in the Southern Oceans is iron-limited, and the supply of iron dissolved from aeolian dust is believed to be the main source from outside the marine reservoir. Glacial sediment sources of iron have rarely been considered, as the iron has been assumed to be inert and non-bioavailable. This study demonstrates the presence of potentially bioavailable Fe as ferrihydrite and goethite in nanoparticulate clusters, in sediments collected from icebergs in the Southern Ocean and glaciers on the Antarctic landmass. Nanoparticles in ice can be transported by icebergs away from coastal regions in the Southern Ocean, enabling melting to release bioavailable Fe to the open ocean. The abundance of nanoparticulate iron has been measured by an ascorbate extraction. This data indicates that the fluxes of bioavailable iron supplied to the Southern Ocean from aeolian dust (0.01–0.13 Tg yr-1) and icebergs (0.06–0.12 Tg yr-1) are comparable. Increases in iceberg production thus have the capacity to increase productivity and this newly identified negative feedback may help to mitigate fossil fuel emissions

Diversity and abundance of solitary and primitively eusocial bees in an urban centre: a case study from Northampton (England)

The apparent reduction of solitary and primitively eusocial bees populations has remained a huge concern over the past few decades and urbanisation is considered as one of the factors affecting bees at different scales depending on bee guild. As urbanisation is increasing globally it necessitates more research to understand the complex community dynamics of solitary and primitively eusocial bees in urban settings. We investigated the urban core of a British town for diversity and abundance of solitary bees using standardized methods, and compared the results with nearby meadows and nature reserves. The study recorded 48 species within the town, about 22 % of the total species and 58 % of the genera of solitary bees in the United Kingdom. Furthermore we found the urban core to be more diverse and abundant in solitary and primitively eusocial bees compared to the meadows and nature re-serves. Of particular note was an urban record of the nationally rare Red Data Book species Coelioxys quadridentata and its host Anthophora quadrimaculata. This research demonstrates that urban settings can contribute significantly to the conservation of solitary and primitively eusocial bees in Britain

Perspectivas filosóficas do uso da tecnologia no cuidado de enfermagem em terapia intensiva

O contexto de assistência à saúde vem sendo influenciado por mudanças produzidas no âmbito da tecnologia o que tem gerado diversas inquietações e indagações acerca dos benefícios, riscos e das relações construídas entre trabalhadores, doentes e a utilização de máquinas como instrumentos imprescindíveis ao cuidado. O objetivo deste artigo foi refletir sobre o uso da tecnologia no cuidado de enfermagem ao doente crítico em terapia intensiva. Espera-se com estas reflexões minimizar arestas que permeiam os ambientes tecnologizados como a terapia intensiva e as concepções de cuidado de enfermagem que neste campo da assistência em saúde envolve o uso de máquinas e equipamentos que oferecem suporte avançado de vida.The context of health assistance has been influenced by changes which are produced in the dimension of technology. They have triggered a lot of inquietude and questioning regarding benefits, risks, and relations constructed among workers and sick, and the use of machines as indispensable tools for care. This paper aims at reflecting on the use of technology in nursing care given to the critical sick in the intensive care unit. It is expected that this reflection can minimize doubts which permeate technological environments, such as the intensive care unit, and the conceptions of nursing care since it involves the use of machines and equipment which provide advanced life support in this field of health assistance.El contexto de atención a la salud viene siendo influenciado por cambios producidos en el ámbito de la tecnología lo que tiene generando diversas inquietudes e indagaciones acerca de los beneficios, riesgos y de las relaciones construidas entre trabajadores, enfermo y la utilización de máquinas como instrumentos imprescindibles al cuidado. El objetivo de este artículo fue reflexionar sobre el uso de la tecnología en el cuidado de enfermería al enfermo crítico en terapia intensiva. Se espera con estas reflexiones minimizar aristas que permean los ambientes tecnologizados como la terapia intensiva y las concepciones de cuidado de enfermería que en este campo de la asistencia en salud envuelve el uso de máquinas y equipamientos que ofrecen soporte avanzado de vida