today one of the most important problems in agriclimatology in effecting of climate on products. one of the climate elements in freezing which according to the continuity , extend and amount of it on agricultural activities ,transportation and invironment has a lot of affections. least temperature forcasts as one of the important climatic elements to forcasting late coldness and freezing in spr...

the aim of this research is recognizing synoptic patterns of the level 500 hp occurrence of late spring freezes over kurdistan province during 1965-2005. after determining freeze temporal-spatial threshold, 22 freezing days spreading over the region were extracted. then, level 500 hp height data located in a scope of 25-60 northern latitude and 30-60 eastern longitude was formulated as an s-mod...

Hatchlings of the painted turtle (Chrysemys picta marginata) are unique as the only reptile and highest vertebrate life form known to tolerate the natural freezing of extracellular body fluids during winter hibernation. Turtles survived frequent exposures to temperatures as low as -6 degrees C to -8 degrees C in their shallow terrestrial nests over the 1987-1988 winter. Hatchlings collected in ...

This research discusses the progress of democracy in Egypt after Arab Spring. When Spring expanded Middle East to Egypt, it was considered beginning a transition towards country managed by concept democracy. The Spring, which has been turmoil since early 2011, become rise mass movement demand changes socio-political order. initially expected create that guaranteed equality and social justice. H...

Winter survial during an annual cycle of temperateand boreal-zone woody perennials is a multicomponent response. Two of these components are: (1) the timing, rate, and extent of cold acclimation (CA; Box 1), and (2) plants’ ability to sufficiently maintain its freezing tolerance (FT) until the danger of killing frosts is passed which is determined by, among other factors, plants’ ability to res...

Winter rapeseed seedlings are susceptible to low temperature during overwintering in Northwest China, leading reduced crops production. Freezing stress is one of the main environmental stresses China from late autumn early spring, an eventful period for overwinter survival rate winter rapeseed. However, molecular mechanism freezing tolerance formation still very backward In this study, using a ...

This study tests whether ERS-2 and Radarsat Standard Beam SAR data could be used to detect spring green-up of broadleaf forests on ̄ oodplains in interior Alaska. SAR data were acquired for preand post-budburst dates during the spring of 1997, 1998 and 1999. The images were radiometrically calibrated todB and then geometrically co-registered to a colour infrared Landsat TM image. Ten broadleaf ...

Superoxide dismutase (SOD) gene expression was investigated to elucidate its role in drought and freezing tolerance in spring and winter wheat (Triticum aestivum). cDNAs encoding chloroplastic Cu/ZnSODs and mitochondrial MnSODs were isolated from wheat. MnSOD and Cu/ZnSOD genes were mapped to the long arms of the homologous group-2 and -7 chromosomes, respectively. Northern blots indicated that...

Vernalization is an essential process by which many temperate plant species acquire competence for flowering. Brachypodium distachyon is a model plant for temperate grasses including many cool-season forage and turfgrasses and cereals. Grasses with spring growth habit do not require vernalization for flowering and are typically less winter hardy. Yet the connection between vernalization and fre...