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51.
Indra Sandal Amita Bhattacharya Uksha Saini Devinder Kaur Shveta Sharma Ashu Gulati Jonnala K Kumar Neeraj Kumar Jyotsna Dayma Pralay Das Bikram Singh Paramvir S Ahuja 《BMC chemical biology》2011,11(1):1-13
Background
Accidental autoclaving of L-glutamine was found to facilitate the Agrobacterium infection of a non host plant like tea in an earlier study. In the present communication, we elucidate the structural changes in L-glutamine due to autoclaving and also confirm the role of heat transformed L-glutamine in Agrobacterium mediated genetic transformation of host/non host plants.Results
When autoclaved at 121°C and 15 psi for 20 or 40 min, L-glutamine was structurally modified into 5-oxo proline and 3-amino glutarimide (α-amino glutarimide), respectively. Of the two autoclaved products, only α-amino glutarimide facilitated Agrobacterium infection of a number of resistant to susceptible plants. However, the compound did not have any vir gene inducing property.Conclusions
We report a one pot autoclave process for the synthesis of 5-oxo proline and α-amino glutarimide from L-glutamine. Xenobiotic detoxifying property of α-amino glutarimide is also proposed. 相似文献52.
Navdeep Goyal 《Pramana》1993,40(2):97-105
In this paper we report the electrical and photoelectrical properties of AgInSe2. Nyquist plots for AgInSe2, obtained at different temperatures, are perfect arcs of a semicircle with their centres lying below the abscissa at an angleα. Finite values ofα (the distribution parameter) clearly indicate a multirelaxation behaviour. Transient and steady state photoconductivity of
AgInSe2 has been studied at different temperatures and illumination levels. The lnI
ph vs lnF curves at different temperatures follow the empirical relation:I
ph ∝F
γ. Values of γ are close to 0.5 at all the temperatures, suggesting a bimolecular recombination. Decay of the photocurrent,
when the illumination is switched off, shows that during decay, photocurrent has two components, i.e. a fast decay in the
beginning and a slow decay thereafter. Decay time constant for slow decay process decreases with increasing temperature, suggesting
that recombination is a thermally activated process in the temperature range studied. 相似文献
53.
54.
S. K. Goyal D. Morin F. Nebebe 《The Journal of the Operational Research Society》1992,43(12):1173-1178
A new type of replenishment policy is suggested for an inventory item having a finite shortage cost and linear trend in demand over a finite time horizon. The optimal solution of the suggested replenishment policy has a lower total cost as compared with the optimal solution for the traditional replenishment policies. 相似文献
55.
56.
We report a combined use of small-angle neutron scattering (SANS) and small-angle X-ray scattering (SAXS) to the study of
counterion condensation in ionic micelles. Small-angle neutron and X-ray scattering measurements have been carried out on
two surfactants cetyltrimethylammonium bromide (CTABr) and cetyltrimethylammonium chloride (CTACl), which are similar but
having different counterions. SANS measurements show that CTABr surfactant forms much larger micelles than CTACl. This is
explained in terms of higher condensation of Br− counterions than Cl− counterions. SAXS data on these systems suggest that the Br− counterions are condensed around the micelles over smaller thickness than those of Cl− counterions. 相似文献
57.
This communication points out a couple of early publications on the power-of-two scheduling scheme that has been consistently ignored by researchers in the past. 相似文献
58.
This paper deals with the problem of determining economic maintenance frequency for a group of machines. The operating cost for each machine is assumed to increase with time since the last maintenance work carried out on the machine. The cost of carrying out maintenance work is known and assumed constant. A fixed cost is incurred whenever maintenance work is carried out, and this fixed cost is assumed to be independent of the number of machines on which maintenance work is carried out. The total cost of the system is given by the sum of maintenance and operating costs for all the machines. A heuristic method is proposed for determining the economic maintenance frequency of each machine. An example is given to illustrate the method. 相似文献
59.
60.