Corpuscles of Stannius of freshwater catfish, Clarias Batrachus

O presente artigo estuda o número, localização e estrutura citológica dos corpúsculos de Stannius do bagre de água doce Clarias batrachus. Ocorre apenas um tipo celular e as células são eosina +, AF + e PAS +

Acute Toxicity Of Euphorbia Royleana Boiss (Euphorbiaceae) latex on freshwater catfish, Heteropneustes Fossilis (Siluriformes, Heteropneustidae) Toxicidad aguda del látex de Euphorbia royleana Boiss (Euphorbiaceae) en el bagre de agua dulce, Heteropneutes fossilis (Siluriformes, Heteropneustidae)

An acute toxicity test was performed by using a four-day static renewal test to determine the LC50 value of aqueous extract of Euphorbia royleana latex for the freshwater fsh, Heteropneustes fossilis. The LC50 values, their upper and lower confdence limits and slope functions were calculated. The LC50 values for aqueous extract of Euphorbia royleana latex at various exposure periods were 7.758 mg/L for 24 h, 5.847 mg/L for 48 h, 4.474 mg/L for 72 h and 3.090 mg/L for 96 h. The regression coeffcient showed that there was signifcant negative correlation between exposure time and different LC values. Hence, it is concluded that the concentration to produce toxicity of latex of Euphorbia royleana is comparable and close to the concentration to produce toxicity of synthetic organophosphates pesticides for the fsh H. fossilis. Therefore, adequate precautions must be taken when Euphorbia royleana latex is being used near fsh- inhabited areas.<br>La prueba de la toxicidad aguda fue realizada utilizando un test estático con renovación, de cuatro días de duración, para determinar el valor de la CL50 de un extracto acuoso del látex de Euphorbia royleana, en el pez de agua dulce Heteropneustes fossilis. Se calcularon el valor de la CL50, los límites de confanza máximo y mínimo y la pendiente. Los valores de la CL50 para el extracto acuoso del látex en varios períodos de exposición fueron 7,758 mg/L para 24 h, 5,847 mg/L para 48 h, 4,474 mg/L para 72 h y 3,090 mg/L para 96 h. El coefciente de regresión mostró una correlación negativa signifcativa entre el tiempo de exposición y diferentes valores de la CL50. Se concluye que la concentración del látex de E. royleana que produce toxicidad es comparable y cercana a la de los plaguicidas sintéticos organofosforados para el pez H. fossilis. Por lo tanto, se deben tomar precauciones adecuadas cuando el látex de E. royleana es utilizado cerca de áreas donde habita el pez H. fossilis

THEORETICAL STUDIES ON THE ELECTRONIC SPECTRA OF AlCl

Author Institution: Department of Physics, Udai Pratap Autonomous College, Varanasi-221002, IndiaThe spectra of AlCl molecule are of astrophysical interest since AlCl has been detected in the envelope of the carbon star IRC + 10216 by microwave spectroscopy. Ab initio and Density Functional Theory calculations on the spectra and structure of AlCl molecule and their cation are carried out. The Einstein A spontaneous emission coefficients for the ro-vibrational transitions in the A$^1 \Pi$-X $^1 \Sigma^+$ electronic band systems of AlCl molecule for v = 0 - 4 and J = 0-100 in each electronic state have been computed using LEVEL program. The values of radiative lifetimes of A$^1 \Pi$ state for v$^\prime \leq$ 9 levels are determined. We have obtained the high transition probabilities for the diagonal bands in this electronic system. The results obtained in the present work are found in agreement with the experimental value