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381.
Two troupes of bonnet monkeys (Macaca radiata) occupying a garden sector of Bangalore were studied mainly for their social behaviour and it was found that though in their behaviour, the bonnets comply with the general behavioural patterns characteristic of Primates, there exist a few features and expressions which are different.Bonnets live in well organised societies near human habitations and feed on wild and cultivated items of food. The troupe size ranges from 10 to 50 members that include males and females of all age groups. No real solitary bonnet has yet been encountered. They occupy definitely demarcated home ranges which overlap those of the others resulting in occasional fights or aggressive behaviour. They roost in many selected quarters, preferably tall and well spread trees (Rahaman & Parthasarathy, 1969). Though bonnets appear to be mostly ground dwellers, their adaptation to arboreal life provides safety. Adult males drop to the rear during flights in danger and see that the rest of the members are safe on tree-tops. They have a communicative system involving gestures, grimaces and calls (Rahaman & Parthasarathy, 1968).The main breeding period is during the months of October and November. The period of the highest frequency of copulations in rhesus monkey of North India coincides fairly with that of bonnets, suggesting that the seasonal factors, to a considerable extent, control the onset of mating season and consequently the births. Babies are born mostly during the months of February and March. The gestation period appears to be of about 5 months duration. The mother-infant relation is most intimate and pronounced during the first 2 months of the baby's life and there is a gradual fall in this aspect as the baby becomes older. 相似文献
382.
P. R. Parthasarathy 《Journal of mathematical biology》1979,7(1):95-97
We modify a Markov branching process such that each particle produces offspring only if its life length is greater than T. We find exact expressions for the mean number of particles at time t. 相似文献
383.
N Ramasubbu R Parthasarathy 《International journal of peptide and protein research》1989,33(5):328-334
Crystals of the dipeptide, pyroglutamyl-alanine (C8H12N2O4) grown from aqueous methanol are monoclinic, space group P2(1) with the following cell parameters: a = 4.863(2), b = 16.069(1), c = 6.534(2)A and beta = 109.9(2) degrees, V = 480.0A3, Mr = 200.2, Dc = 1.385 g cm-3, and Z = 2. The crystal structure was solved by the application of direct methods and refined to an R value of 0.044 for 699 reflections with I greater than 2 sigma. The amide of the pyroglutamyl side chain is cis, omega 1 = 2.6(7) degrees; the peptide unit is trans and appreciably non-planar (omega 2 = 167.4(5) degrees). The backbone torsional angles are: psi 1 = 166.1(5), phi 2 = -90.3(6), and psi 2 = -22.4(6) degrees. This structure contains a short (2.551(5)A) intermolecular hydrogen bond between the carboxyl OH and the N-acyl oxygen, a feature common to most acyl amino acids and acyl peptides. 相似文献
384.
Cytoplasmic microfilaments in plant cells 总被引:3,自引:0,他引:3
385.
R Murali E Subramanian R Parthasarathy 《International journal of peptide and protein research》1986,27(5):478-482
The crystal structure of t-Boc-glycyl-L-phenylalanine (C14H22N2O5, molecular weight = 298) has been determined. Crystals are monoclinic, space group P2(1), with a = 7.599(1) A, b = 9.576(2), c = 12.841(2), beta = 97.21(1) degrees, Z = 2, Dm = 1.149, Dc = 1.168 g X cm-3. Trial structure was obtained by direct methods and refined to a final R-index of 0.064 for 1465 reflections with I greater than 1 sigma. The peptide unit is trans planar and is nearly perpendicular to the plane containing the urethane moiety. The plane of the carboxyl group makes a dihedral angle of 16.0 degrees with the peptide unit. The backbone torsion angles are omega 0 = -176.9 degrees, phi 1 = -88.0 degrees, psi 1 = -14.5 degrees, omega 1 = 176.4 degrees, phi 2 = -164.7 degrees and psi 2 = 170.3 degrees. The phenylalanine side chain conformation is represented by the torsion angles chi 1 = 52.0 degrees, chi 2 = 85.8 degrees. 相似文献
386.