128 research outputs found
The first polluted river? Repeated copper contamination of fluvial sediments associated with Late Neolithic human activity in southern Jordan
The roots of pyrometallurgy are obscure. This paper explores one possible precursor, in the Faynan Orefield in southern Jordan. There, at approximately 7000 cal. BP, banks of a near-perennial meandering stream (today represented by complex overbank wetland and anthropogenic deposits) were contaminated repeatedly by copper emitted by human activities. Variations in the distribution of copper in this sequence are not readily explained in other ways, although the precise mechanism of contamination remains unclear. The degree of copper enhancement was up to an order of magnitude greater than that measured in Pleistocene fluvial and paludal sediments, in contemporary or slightly older Holocene stream and pond deposits, and in the adjacent modern wadi braidplain. Lead is less enhanced, more variable, and appears to have been less influenced by contemporaneous human activities at this location. Pyrometallurgy in this region may have appeared as a byproduct of the activity practised on the stream-bank in the Wadi Faynan ~7000 years ago
La mutación de la biblioteca en los inicios del siglo XXI
El papel que las bibliotecas desempeñan en la actualidad ha sido cuestionado en
numerosas ocasiones, a causa de la revolución tecnológica a la que se está asistiendo,
la cual pondría en amenaza el papel básico que hasta ahora tenían éstas. Pero la
realidad es que se observa una tendencia en la que cada vez se construyen más
bibliotecas y más complejas. Por lo que se torna harto interesante descubrir hacia dónde
camina la arquitectura en este sentido.
A este respecto, se advierte un cambio de paradigma respecto al papel que juega la
biblioteca en la actualidad, provocando a su vez una respuesta en cuanto a la
arquitectura bibliotecaria. Los cambios sociales que se han producido de la mano del
desarrollo de la tecnología, se han visto implicados de forma directa e indirecta en este
cambio de paradigma, presentando los desafíos a los que se enfrenta la arquitectura
actual.
Debido a la incertidumbre que se presenta de cara a este nuevo periodo, en base a los
constantes cambios que se manifiestan debido a la rápida evolución que sufren las
nuevas tecnologías, y de cara a las demandas de esta nueva sociedad, se torna
fundamental la aplicación del principio de la flexibilidad en los nuevos espacios
bibliotecarios, pero se rehúye de la clásica solución espacial donde el espacio se vuelve
uniforme, sin apenas expresión plástica ni variedad.
Por otro lado, se presentan los temidos efectos que la globalización tiene sobre el planeta,
a cualquier escala, y que parecen llevar todo hacia una tendencia universalista. Por lo
que se hace interesante el estudio de la arquitectura bibliotecaria desde diferentes
ópticas a nivel cultural, tomando como referencia la cultura occidental, debido a su
importante papel de cara al origen de este proceso, así como la cultura oriental, definida
prácticamente como la antítesis de ésta.
Sobre la base de lo planteado, la presente investigación, a modo de primera toma de
contacto, ha pretendido abrir un campo de estudio a través del cual se puedan
identificar nuevas formas de aplicar la flexibilidad en los espacios bibliotecarios, de cara
a que éstos no se vuelvan caducos en cuanto al diseño que presentan, además de poner
el causa los procesos de globalización que pretenden reducir la realidad actual, en base
a procesos de homogeneización; por lo que se busca identificar procesos de hibridación
en la arquitectura actual, a través de los cuales poder identificar si se producen
diferencias entre las distintas culturas, valorando en qué medida se incluyen las cuestiones
de carácter local en las obras que representan cada una de estas culturas.
A través de la metodología empleada, basada en los estudios de caso individual y en el
análisis comparativo de éstos, se han podido evidenciar líneas que muestran esa
evolución de la arquitectura actual, en la que se torna evidente la importancia que tiene
la flexibilidad en el nuevo escenario, así como la posibilidad de aplicarla de diversa
manera, además de reconocerse los mencionados procesos de hibridación, permitiendo
establecer diferencias entre las dos culturas, desmontando así la ambiciosa visión de
carácter unilateral que se tenía sobre la globalización.Abstract: The role played by libraries nowadays has been frequently questioned in view of the
technological revolution currently underway, which would seem to threaten the basic
function libraries had up until now. However, what we are actually seeing is a trend in which
a growing number of increasingly complex libraries are being built. Therefore, it is of interest
to take a look at where architecture in this sector is heading.
The truth is, a change can be observed in what is considered to be the model role of
libraries today, which in turn leads to a different response in terms of their architecture. The
social changes that have taken place as a result of developments in technology have
played both a direct and indirect role in such a change of model and represent the
challenges facing current architecture.
Given the uncertainty that exists these days due to the constant changes occurring as a
result of the rapid evolution of new technologies and of society’s new demands, it has
become essential to build a flexibility component into all new library design concepts,
while shying away from the classic solution of uniform spaces with little plastic variety or
expression.
On the other hand, the effects of globalisation present at all scales of life on this planet
inevitably arise and tend to drive everything towards a common universality. So it is
interesting to study the architecture of libraries from different cultural perspectives, firstly in
Western culture, given the important role it has played in the origin of this process, and
subsequently from the viewpoint of Oriental culture, practically defined as the antithesis of
the former.
On the basis of the above premises, this paper seeks to stand as the initial contact in a line
of research that identifies new ways of applying flexibility into the architecture of libraries
so that they do not become obsolete in terms of their design, as well as identifying the
globalisation processes that seek to reduce current reality through homogenisation
procedures. Therefore, it aims to identify hybridisation processes in current architecture that
serve to ascertain whether distinctions occur between different cultures and to assess the
extent to which local issues find a place in iconic buildings representing each of those
cultures.
By means of the methodology used, based on individual case studies and comparative
analysis of each, certain traits have been revealed that show an evolution in
contemporary architecture, in which greater importance is given in this new scenario to
flexibility and the ability to apply it in different ways, as well as acknowledging the aforementioned
hybridization processes, enabling differences between the two cultures to be
identified and thus any narrow-minded view of globalization as a unilateral phenomenon
to be dismantled
Neurobehavioral consequences of chronic intrauterine opioid exposure in infants and preschool children: a systematic review and meta-analysis
<b>Background</b><p></p>
It is assumed within the accumulated literature that children born of pregnant opioid dependent mothers have impaired neurobehavioral function as a consequence of chronic intrauterine opioid use.<p></p>
<b>Methods</b><p></p>
Quantitative and systematic review of the literature on the consequences of chronic maternal opioid use during pregnancy on neurobehavioral function of children was conducted using the Meta-analysis of Observational Studies in Epidemiology (MOOSE) and the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) guidelines. We searched Cinahl, EMBASE, PsychINFO and MEDLINE between the periods of January 1995 to January 2012.<p></p>
<b>Results</b><p></p>
There were only 5 studies out of the 200 identified that quantitatively reported on neurobehavioral function of children after maternal opioid use during pregnancy. All 5 were case control studies with the number of exposed subjects within the studies ranging from 33–143 and 45–85 for the controls. This meta-analysis showed no significant impairments, at a non-conservative significance level of p < 0.05, for cognitive, psychomotor or observed behavioural outcomes for chronic intra-uterine exposed infants and pre-school children compared to non-exposed infants and children. However, all domains suggested a trend to poor outcomes in infants/children of opioid using mothers. The magnitude of all possible effects was small according to Cohen’s benchmark criteria.<p></p>
<b>Conclusions</b><p></p>
Chronic intra-uterine opioid exposed infants and pre-school children experienced no significant impairment in neurobehavioral outcomes when compared to non-exposed peers, although in all domains there was a trend to poorer outcomes. The findings of this review are limited by the small number of studies analysed, the heterogenous populations and small numbers within the individual studies. Longitudinal studies are needed to determine if any neuropsychological impairments appear after the age of 5 years and to help investigate further the role of environmental risk factors on the effect of ‘core’ phenotypes
An ecological future for weed science to sustain crop production and the environment. A review
Sustainable strategies for managing weeds are critical to meeting agriculture's potential to feed the world's population while conserving the ecosystems and biodiversity on which we depend. The dominant paradigm of weed management in developed countries is currently founded on the two principal tools of herbicides and tillage to remove weeds. However, evidence of negative environmental impacts from both tools is growing, and herbicide resistance is increasingly prevalent. These challenges emerge from a lack of attention to how weeds interact with and are regulated by the agroecosystem as a whole. Novel technological tools proposed for weed control, such as new herbicides, gene editing, and seed destructors, do not address these systemic challenges and thus are unlikely to provide truly sustainable solutions. Combining multiple tools and techniques in an Integrated Weed Management strategy is a step forward, but many integrated strategies still remain overly reliant on too few tools. In contrast, advances in weed ecology are revealing a wealth of options to manage weedsat the agroecosystem levelthat, rather than aiming to eradicate weeds, act to regulate populations to limit their negative impacts while conserving diversity. Here, we review the current state of knowledge in weed ecology and identify how this can be translated into practical weed management. The major points are the following: (1) the diversity and type of crops, management actions and limiting resources can be manipulated to limit weed competitiveness while promoting weed diversity; (2) in contrast to technological tools, ecological approaches to weed management tend to be synergistic with other agroecosystem functions; and (3) there are many existing practices compatible with this approach that could be integrated into current systems, alongside new options to explore. Overall, this review demonstrates that integrating systems-level ecological thinking into agronomic decision-making offers the best route to achieving sustainable weed management
The zinc transporter ZIP12 regulates the pulmonary vascular response to chronic hypoxia
The typical response of the adult mammalian pulmonary circulation to a low oxygen environment is vasoconstriction and structural remodelling of pulmonary arterioles, leading to chronic elevation of pulmonary artery pressure (pulmonary hypertension) and right ventricular hypertrophy. Some mammals, however, exhibit genetic resistance to hypoxia-induced pulmonary hypertension1, 2, 3. We used a congenic breeding program and comparative genomics to exploit this variation in the rat and identified the gene Slc39a12 as a major regulator of hypoxia-induced pulmonary vascular remodelling. Slc39a12 encodes the zinc transporter ZIP12. Here we report that ZIP12 expression is increased in many cell types, including endothelial, smooth muscle and interstitial cells, in the remodelled pulmonary arterioles of rats, cows and humans susceptible to hypoxia-induced pulmonary hypertension. We show that ZIP12 expression in pulmonary vascular smooth muscle cells is hypoxia dependent and that targeted inhibition of ZIP12 inhibits the rise in intracellular labile zinc in hypoxia-exposed pulmonary vascular smooth muscle cells and their proliferation in culture. We demonstrate that genetic disruption of ZIP12 expression attenuates the development of pulmonary hypertension in rats housed in a hypoxic atmosphere. This new and unexpected insight into the fundamental role of a zinc transporter in mammalian pulmonary vascular homeostasis suggests a new drug target for the pharmacological management of pulmonary hypertension
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An initial biogeochemical investigation at Cors Goch, Anglesey (North Wales, UK)
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Pronounced human mortality events coincident with volcanogenic air pollution
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