Aloe barbadensis: how a miraculous plant becomes reality

Aloe barbadensis Miller is a plant that is native to North and East Africa and has accompanied man for over 5,000 years. The aloe vera plant has been endowed with digestive, dermatological, culinary and cosmetic virtues. On this basis, aloe provides a range of possibilities for fascinating studies from several points of view, including the analysis of chemical composition, the biochemistry involved in various activities and its application in pharmacology, as well as from horticultural and economic standpoints. The use of aloe vera as a medicinal plant is mentioned in numerous ancient texts such as the Bible. This multitude of medicinal uses has been described and discussed for centuries, thus transforming this miracle plant into reality. A summary of the historical uses, chemical composition and biological activities of this species is presented in this review. The latest clinical studies involved in vivo and in vitro assays conducted with aloe vera gel or its metabolites and the results of these studies are reviewed

Simulation of peri-urban growth dynamics using weights of evidence approach

The study aims to simulate the peri-urban growth dynamics in a growing region of India using Weights of Evidence (WOE) based cellular automata model. The growth process was expressed as a function of four causative variables corresponding to which seven data layers were generated in a Geographic Information Systems environment. The model was calibrated for the period 2000–2005 using Kappa indices and fuzzy set theory based two way comparison method. The Kappa value was 0.7, while the value of Klocation and Khisto were 0.81 and 0.93, respectively. The fuzzy similarity values increased for small to large neighbourhood sizes which showed that the model was able to simulate the contiguous and dense growth. However, for dispersed and isolated growth the model showed less accuracy. The model was validated for period 2005–2010 and revealed a Kappa value of 0.88, while value of Klocation and Khisto were 0.91 and 0.96, respectively

Spatio - temporal variations of urban heat island over Delhi

Temporal and spatial trends of the surface urban heat island (UHI) formation over Delhi are examined with respect to aerosol load and land-cover variations. The study reveals that temperatures over Delhi are higher than those over the surrounding regions almost through-out the year during the night time. The nocturnal heat island intensity is minimum (0–2 K) during the monsoon months and maximum during the month of March (4–6 K). The UHI trends during the day-time are however, significantly different. It is observed that a day-time cool island forms over Delhi twice during the year in the months of May–June and October–December. Analysis of temporal variations in urban heat island intensity (UHII) and aerosol load over Delhi reveals a significant negative correlation between UHII and aerosol optical depth (AOD). Spatial analysis of LST, land-cover and AOD for the months of March, May and November confirms the significant role of AOD along with land-cover variables such as percentage area under the classes built-up, rock, vegetation and bare soil. Comparative analysis of LST in the regions lying north, south, east and west of Delhi in relation to the prevailing land-cover suggests that thermal inertia is also a very important factor determining the urban-rural thermal structure