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Spatial patterns in communities of aquatic macroinvertebrates of Argentinean Puna. The macroinvertebrates are a vital component of freshwater ecosystems as they contribute to the process of organic matter while serving as food for other organisms such as fish and amphibians. Unfortunately, the knowledge of the aquatic diversity is poor in the high Andean systems (between 3 200 and 5 200 m.a.s.l. and rainfall below 300 mm per year), especially in the Argentinean peatbogs, a fact which has made difficult the interpretation of spatial patterns on a regional scale. The present study aimed to describe the composition of aquatic macroinvertebrates in seven peatbogs in the Argentinean Puna, and to analyze for the first time their spatial patterns. For this, we studied the relationship of these organisms with the environment, and obtained information about the surrounding vegetation and water physico-chemical characteristics. A total of 3 131 specimens of aquatic macroinvertebrates were collected, representing 25 taxa belonging to 22 families and 24 genera. In addition, 62 species of vascular plants were recorded, belonging to 20 families. The most abundant life form were the tufted grasses, followed by cushions. By using an NMDS (Non-Metrical Multidimensional Scaling) statistical analysis, the sampling sites were ordered in each peatbog as follows. The peatbogs located furthest West and South with higher water temperature were grouped on axis 1, whereas those with higher conductivity, whole water dissolved solids and salt concentration were grouped on axis 2. The water temperature was higher than air temperature at all times, and we found no association between temperature and altitude. The altitude had no correlation with the abundance of macroinvertebrates or with plant richness. Life forms such as scattered graminoids, trailing and prostrate herbs (in many cases they get into the channel) and aquatic plants were more abundant in peatbogs 4, 5 and 7 and they had a correlation with some macroinvertebrates belonging to functional trophic groups such as filter-collectors, collectors and scrapers. Finally, conductivity, whole dissolved solids and salt concentration had their highest value in peatbog 6, where Bivalvia (filter-collector) and Hyalella (collector) were also found. The results obtained attest that these macroinvertebrates displayed diversity and composition spatial patterns, the most important feature being their relationship with the surrounding vegetation, and to a lesser extent, with the physical and chemical traits of water in seven fertile lowlands in the Argentinean Puna.

Objective: Age related macular degeneration (ARMD) in its neovascular form is a serious disease which produces legal blindness in many patients with poor prognosis if left untreated. We intend to establish a clinical guide with the different therapeutic options that exist nowadays, which may help the ophthalmologists in their clinical practice., Methods: A group of medical retina experts selected by SERV have evaluated the results of different published studies with the drugs currently available, obtaining an evidence-based consensus. Some recommendations have been established for diagnosis, treatment and monitoring of patients with neovascular ARMD., Results: The intravitreal injection of ranibizumab at a dosage of 0.5 mg produces significant improvement of visual acuity in subfoveal lesions, according to data obtained from studies with the highest level of evidence. It should be considered as a first choice drug. The use of bevacizumab, a drug with not approved indication for intraocular use, nor for the treatment of neovascular ARMD can reach a result which is closer to the ones obtained with ranibizumab than to those obtained with photodynamic therapy (PDT) and pegaptanib. The use of intravitreal pegaptanib sodium in intravitreal injection at a dosage of 0.3 mg as a treatment for subfoveal lesions can obtain similar results to the TFD, but with a wider range of injuries., Conclusion: The results of the evidence-based studies are a good guide for the treatment of this disease.