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Hemisphere Sites (hemisphere + site)
Selected AbstractsLinking flux network measurements to continental scale simulations: ecosystem carbon dioxide exchange capacity under non-water-stressed conditionsGLOBAL CHANGE BIOLOGY, Issue 4 2007KATHERINE E. OWEN Abstract This paper examines long-term eddy covariance data from 18 European and 17 North American and Asian forest, wetland, tundra, grassland, and cropland sites under non-water-stressed conditions with an empirical rectangular hyperbolic light response model and a single layer two light-class carboxylase-based model. Relationships according to ecosystem functional type are demonstrated between empirical and physiological parameters, suggesting linkages between easily estimated parameters and those with greater potential for process interpretation. Relatively sparse documentation of leaf area index dynamics at flux tower sites is found to be a major difficulty in model inversion and flux interpretation. Therefore, a simplification of the physiological model is carried out for a subset of European network sites with extensive ancillary data. The results from these selected sites are used to derive a new parameter and means for comparing empirical and physiologically based methods across all sites, regardless of ancillary data. The results from the European analysis are then compared with results from the other Northern Hemisphere sites and similar relationships for the simplified process-based parameter were found to hold for European, North American, and Asian temperate and boreal climate zones. This parameter is useful for bridging between flux network observations and continental scale spatial simulations of vegetation/atmosphere carbon dioxide exchange. [source] Comparison between seasons of the ultraviolet environment in the shade of trees in AustraliaPHOTODERMATOLOGY, PHOTOIMMUNOLOGY & PHOTOMEDICINE, Issue 2 2001A. V. Parisi Background/Purpose: This paper has considered the erythemal UV (UVery), UVA and visible irradiances in the shade of Australian trees for each season at a sub-tropical southern hemisphere site. Methods: The irradiances in tree shade have been measured with radiometers as a percentage of the irradiances in the sun for each season of the year. Results: Although the solar irradiances are lower in winter, the percentages of the UV in tree shade compared to the UV in full sun are marginally higher (by up to 7%) in the winter compared to summer. The range of percentages for UVery was up to double that of the percentages of the visible waveband. The percentages for UVery were also higher than for the UVA waveband. The percentages of the irradiances in the tree shade compared to full sun are 8,14% lower at noon compared to the morning and afternoon for the UVery waveband. The ratio of UVA to UVery is lower in the tree shade compared to the full sun. Conclusions: The UVA to UVery ratio is expected to be even lower in the tree shade as a result of ozone depletion. This, combined with the visible irradiances in the tree shade not being a reliable indication of the biologically damaging UV irradiances, has consequences for public health and skin cancer prevention. [source] Quality of life in patients with right- or left-sided brain tumours: literature reviewJOURNAL OF CLINICAL NURSING, Issue 11 2008Alvisa Palese Bcsn Aims., To determine if patients with left- or right-sided hemisphere neoplasm perceive their quality of life (QoL) differently. Background., It is not clear whether patients with a lesion in the left hemisphere have a different QoL than those with a lesion in the right hemisphere. (1) In the pre-operative period, patients with a left-sided lesion may have different symptoms according to the position of the tumour. (2) Studies on patients with brain injury demonstrate an association between left frontal lesions and depression: depression can alter the patients' perception of QoL. (3) In the postoperative period, right-handed patients may be disadvantaged by surgical trauma to the motor cortex in the left hemisphere. (4) During the different phases of the disease, the various functions of the two hemispheres may influence the patient's capacity to control QoL; also, as suggested by authors, both the ego and the conscience are mostly located in the left hemisphere. This is the reason that patients with a left-sided lesion may perceive a worse QoL. Methods., A review of literature was carried out using the Medline database (1966,2007) and CINHAL (1982,2007), using the following Mesh Terms and key words: brain neoplasm, tumour or cancer, hemispheric dominance or laterality or right or left hemisphere, QoL. Results., Seven studies emerged that documented non-homogeneous results and which included different populations. The association between QoL and the side of the lesion was evaluated. Conclusions., The lack of a substantial number of recent, robust follow-up studies investigating the QoL in patients at different stages of disease and treatment indicates that more research is needed. Relevance to clinical practice., Understanding the QoL in patients with brain neoplasm and the differences between right and left hemisphere sites of the neoplasm can help nurses develop different interventions and offer more guidance for effective clinical intervention. [source] Assemblage level variation in springtail lower lethal temperature: the role of invasive species on sub-Antarctic Marion IslandPHYSIOLOGICAL ENTOMOLOGY, Issue 3 2009CHARLENE JANION Abstract. It is widely held both in the physiological literature, and more generally, that the average characteristics of species within an assemblage differ among sites. Such generalizations should be based on investigations of whole assemblages at sites, but this is rarely done. Here, such a study is undertaken for virtually the full assemblage of springtails found at sub-Antarctic Marion Island, by investigating supercooling points (SCPs) of 12 of the 16 species that occur there. Assemblage level variation tends to be less than that documented for assemblages across northern hemisphere sites but similar to that found at some Antarctic locations. Across this set of species, the mean SCPs of the indigenous species (mean ± SE =,17.2 ± 0.4 °C) do not differ significantly from that of the invasive species (,16.3 ± 0.7 °C). Overall, the introduction of several species to the island does not appear to have led to functional homogenization (for this trait). By combining the assemblage-level SCP data with information on the abundances of the species in each of four major habitats, it is also shown that severe but uncommon low temperature events could substantially alter species relative abundances. By resetting assemblage trajectories, such events could play an important role in the terrestrial system at the island. [source] | |||||||||||||