Global Gridded Nitrogen Indicators: Influence of Crop Maps.

Displaying Nitrogen (N) indicators on a global grid poses unique opportunities to quantify environmental impacts from N application in different world regions under a variety of conditions. Such calculations require the use of maps showing the geo-spatial distribution of crop production. Although there are several crop maps in the scientific literature to choose from, the consequences of this choice for the calculation of N indicators still need to be evaluated. In this study we analyze the differences in results for N Use Efficiency (NUE) and N surplus calculated on the global scale using two different crop maps (SPAM and M3). For our calculations we used publicly available statistical and literature data combined with each crop map and carefully traced the origins of the differences in the results. Our results showed that the regions most affected by discrepancies caused by differences in crop maps (yields and physical area) are Central Asia and the Russian Federation, Australia and Oceania, and North Africa. However, we also found that the inclusion or exclusion of grass crops influences the results, as does the aggregation of crops to categories. Considering all these differences, we note that M3 seems to provide the more plausible results for the calculation of N indicators. Our analysis not only highlights the importance of determining the critical parameters for N indicator calculation, but also allows key parameters connected with N use and overuse to be identified on the global scale.

Effects of home reading training on reading and quality of life in AMD-a randomized and controlled study.

BACKGROUND: Age-related macular degeneration (AMD) causes reading impairment, reduced quality of life (QoL), and secondary depression. We have shown that support with magnifying aids improved reading speed (RS), emotional and cognitive status, and QoL. The present study investigates whether additional reading training (RT) (after adapting to appropriate visual aids) can further improve vision rehabilitation. METHODS: Patients with dry AMD were randomly assigned to 2 groups. The primary RT group (P-RTG, n = 25) trained with sequentially presented text (RSVP), and the control group (CG, n = 12) performed placebo training (crossword puzzles) and later crossed over to RT, so that altogether 37 participants performed reading training. Patients trained at home on a PC for 6 weeks. RS was assessed during reading printed paragraphs of text aloud. Using a scanning laser ophthalmoscope, we examined fixation stability and preferred retinal locus (PRL) for fixating a cross, as well as PRL and eye movements during reading single words. We assessed emotional status by Montgomery-Åsberg Depression Rating Scale (MADRS), cognitive status by dementia detection test ( DemTect ) and QoL by Impact of Vision Impairment (IVI) profile. Visual acuity and magnification requirement were examined by standard procedures. All variables were measured before and after placebo training, before and after RT, and after 6 weeks without training (follow-up). RESULTS: RS improved significantly in the P-RTG during RT, but not in the CG during placebo training. The effect remained stable at follow-up. Fixation performance and eye movement variables did not change. Emotional status (MADRS) improved in P-RTG during RT and showed a significant difference of the change of scores between the 2 groups. Complete IVI scores improved significantly during RT and remained stable. CONCLUSION: The results indicate that patients with AMD, who already use magnifying aids, benefit from additional RT and that it can contribute in preventing depression and improve QoL. TRIAL REGISTRATION: The study was registered at the German Clinical Trials Register (DRKS00015609).