Pre-monsoon maximum temperatures over New Delhi, Mumbai & Chennai and possible solar influence

Lkkj & o"kZ 1951 ls 2001 rd dh 51 o"kksZa dh vof/k ds fy, ubZ fnYyh] eqEcbZ vkSj psUuS esa ekulwu iwoZ vf/kdre rkieku esa lkekU; fofHkUurkvksa ds lkSj {kksHk [lw;Z ds /kCcksa ¼,l- ,l-½ dh la[;k ds okf"kZd vkSlr ds laca/k esa vkdyu] ds lkFk laHkkfor laca/k dk lkaf[;dh; :Ik ls fo’ys"k.k fd;k x;k gSA rkieku ds Ja`[kykc) vk¡dM+ksa ds vk/kkj ij dsoy psUuS ds fy, rkieku esa o`f) dh izo`fRr dks NksM+dj vU; lHkh dsanzksa ij yxHkx 3 o"kksZa ds vUrjky ij bldh iqujko`fr dk irk pyk gS A lkSj voLFkkvksa ¼o`f) nj fun’kZ dk mi;ksx djds½ dh fofHkUurkvksa ds fo’ys"k.k ls lw;Z dh U;wure vkSj vf/kdre voLFkkvksa ds nkSjku 73 izfr’kr ekeyksa esa rkieku esa o`f) dh izo`fRr dk irk pyk gS A xr o"kZ ds ekulwu iwoZ rkieku vkSj lw;Z ds /kCcksa dh la[;k ds okf"kZd vkSlr ds chp lglaca/k ds xq.kkad :Ik ls ldkjkRed gksus dk irk pyk gS tc lw;Z ds /kCcksa dh la[;k dk okf"kZd vkSlr yxHkx 140 ds pje eku ls vf/kd gks tkrk gS vkSj ;g ¼$0-647½ ubZ fnYyh ds laca/k esa egRoiw.kZ gS A ;g ifj.kke iwohZ Hkkjr ds dsanzksa ds fy, fd, x, blh rjg ds v/;;uksa ds vuq:Ik gS A The general variations of pre-monsoon maximum temperature over New Delhi, Mumbai and Chennai for the 51 years period from 1951 to 2001 and its possible association with solar activity [estimated in terms of annual mean sunspot (SS) numbers] have been analysed statistically. The temperature series indicate an approximate periodicity of 3 years for all the stations with an increasing trend for Chennai only. Analysis of the variations with respect to solar phases (using a growth rate model) indicates an increasing trend of temperature in 73% cases during solar minimum to maximum phases. The correlation coefficient between pre-monsoon temperature and annual mean SS nos. of the preceding year indicate a positive association when the latter exceeds some critical value approximately 140 and it (+0.647) is significant for New Delhi. The present result is consistent with similar studies for stations over eastern India.

Grid maps for spaceflight, anyone? They are for free!

We show that, given extensive exploration of a three-dimensional volume, grid units can form with the approximate periodicity of a face-centered cubic crystal, as the spontaneous product of a self-organizing process at the single unit level, driven solely by firing rate adaptation.

Entrainment of the locomotor rhythm of Carcinus by cycles of salinity change

It is well known that intertidal animals exhibit temporal patterning of behaviour in which locomotor activity occurs at particular times of day and state of tide. Naylor & Atkinson (1976) postulate that such behavioural rhythms are partially controlled by endogenous timing processes which determine the approximate periodicity of a rhythm, as expressed in constant conditions in the laboratory, and that these circadian and circatidal rhythms are entrained by environmental variables which in nature synchronize the expression of behavioural rhythmicity at adaptively appropriate times. Several tidal variables, such as temperature, pressure, light and wave action, have been shown to synchronize and entrain endogenous rhythms (Palmer, 1974; Naylor & Atkinson, 1976) but so far there appears to be little evidence of entrainment of tidal rhythmicity in coastal animals by variations in salinity. A tidal rhythm of responsiveness to water of reduced salinity has been demonstrated by Arnold (1970) in the cirral activity of Balanus balanoides (L.), but entrainment by this response in Balanus has not been tested. In any event the tidal rhythm of cirral activity in Balanus balanoides on the shore is not expressed in barnacles kept in constant conditions in the laboratory (Southward & Crisp, 1965) and therefore appears to be largely controlled by exogenous factors. It therefore seemed worthwhile to investigate the effects of salinity changes upon the locomotor rhythm of Carcinus maenas (L.), the control of which by internal factors (Arechiga, Huberman & Naylor, 1974) and some external factors (Naylor & Atkinson, 1972) is well documented.