Morphologic observations on early retinal synaptogenesis of Macaca mulatta fetuses of known gestational ages are described. Attempt is made to correlate the first appearance of synoptic vesicles, lamellar material, and the establishment of presynaptic contacts in both the inner and outer plexiform layers and in both types of synapses developing in these zones. Possible origin of lamellar materi...

Analysis of observational data suggests two-way interactions between the tropical intraseasonal oscillation (ISO) and synoptic-scale variability (SSV). On one hand, SSV is strongly modulated by the ISO; that is, a strengthened (weakened) SSV appears during the enhanced (suppressed) ISO phase. The northwest– southeast-oriented synoptic wave train is strengthened and well organized in the northwe...

A large wide-field telescope and camera with optical throughput over 200 m deg – a factor of 50 beyond what we currently have – would enable the detection of faint moving or bursting optical objects: from Earth threatening asteroids to energetic events at the edge of the optical universe. An optimized design for LSST is a 8.4 m telescope with a 3 degree field of view and an optical throughput o...

introduction prediction of thunderstorm is one of the most difficult issues in weather forecasting. deep convective clouds develop at small spatial and temporal dimensions about 1-10 km and 1-12 h. various thermodynamic parameters have been discovered over the past 40 years, according to data obtained by radiosounds. the capability of these indices in forecasting instability varies over time an...

in this research the temporal-spatial changing trend of nightly temperatures in isfahan province has been studied with the purpose of manifesting temperature changes, recognition of temperature abnormality and comparison for the two methods of pixel and station. on this basis, the data of the minimum temperature average of 21 synoptic and climatology stations were processed in the said province...

one of atmospheric phenomena of dry and semi-dry areas and areas adjacent to these areas is the phenomenon of dust and production of particulate matter (pm10) that have a lot of environmental hazards. in this research, the purpose is investigation of temporal variations of pm10 concentration during 2005-2010 and influence of meteorological parameters on it. meteorology information have obtained...

climate change is a natural phenomenon that occurs in the long time scale. the most important factors that intensify climate change are changes in reflected radiation from the sun, changes in earth's orbit, greenhouse gases and continents drift. in this research the barandoezchay watershed in west azerbaijan province with an area of 1088 km2 was investigated. due to the lack of synoptic st...

abstract precipitation as the most important factor plays the main role in many application researches which are based on climatic parameters. many researches in the field of hydrology, hydrometeorology and agriculture employs rain-gauges (such as synoptic and climatologic stations) data. precipitation characteristics, such as rainfall intensity and duration, usually exhibit significant spatial...

hail phenomenon is one of the hazardous weather phenomena that can make the highest amount of damage to farms, gardens, cars, rooftops, etc. in a very short time (a few minutes), depending on the diameter of the particles. one of the best ways to study this devastating climatic phenomenon is the use of atmospheric instability indices. the indices which are calculated with the help of radiosonde...

comparison of linear and nonlinear (bilinear) time series models in reference crop evapotranspiration prediction in urmia synoptic stationreference crop evapotranspiration (eto) prediction is one of the important elements in optimizing agricultural water consumption. in this regard, one of the prediction approaches is to use the stochastic time series methods. in this research, ar (p) and arma(...