Neutron supermirrors and supermirror polarizers are thin film multilayer based devices which are used for reflecting and polarizing neutrons in various neutron based experiments. In the present communication, the in-house development of a 9 m long in-line dc sputtering system has been described which is suitable for deposition of neutron supermirrors on large size (1500 mm × 150 mm) substrates and in large numbers. The optimisation process of deposition of Co and Ti thin film, Co/Ti periodic multilayers, and a-periodic supermirrors have also been described.
View Article and Find Full Text PDFThe authors describe the clinical and pathological features of a solitary fibrous tumor of the tentorium, a rare location for the tumor in the CNS. A 52-year-old lady presented to the neurosurgical services with headache of four months and vertigo of one and a half months duration. On examination, she had left-sided cerebellar signs and bilateral papilloedema.
View Article and Find Full Text PDFBackground Context: Epithelioid angiosarcoma (EA) is a high-grade sarcoma of vascular origin. EA is a rare variant of angiosarcoma. It is characterized by large cells with an epethelioid morphology.
View Article and Find Full Text PDFPrimary photochemical paths of alkyl phenyl selenides (1) were investigated, and an origin of large deviations in the chemical yields of products obtained by carbon radical reactions induced by photolysis of phenyl selenides was clarified. KrF excimer laser photolyses of n-pentyl phenyl selenide (1a) yielded 1-pentene (2a), n-pentane (3a), n-decane (4a), dipentyl selenide (5a), benzene (6), dipentyl diselenide (7a), and diphenyl diselenide (7) as major photoproducts, with compounds 2a, 3a, 4a, 5a, and 7 formed by pentyl-Se bond cleavage, and 5a, 6, and 7a by Ph-Se bond cleavage. The selectivity of the photoproducts revealed the occurrence of an unexpected amount of Ph-Se bond cleavage (35% in n-hexane at 248 nm) during photolysis.
View Article and Find Full Text PDFAndrographolide 1, the cytotoxic agent of the plant Andrographis paniculata was subjected to semi-synthetic studies leading to the preparation of a number of potent and novel analogues. Of the analogues synthesized, while 8,17-epoxy andrographolide 6 retained the cytotoxic activity of 1, ester derivatives of 6 exhibited considerable improvement in activity. Lower activity was observed when the epoxy moiety in the triacetate 9, derived from 6 was modified.
View Article and Find Full Text PDFAndrographis paniculata extract is traditionally used as a medicine to treat different diseases in India, China and Southeast Asia. In the present study, we evaluated the anticancer and immunomodulatory activity of the methanolic extract of Andrographis paniculata in human cancer and immune cells. The methanolic extract of Andrographis paniculata was fractionated into dichloromethane, petroleum ether and aqueous extracts and screened for bioactivity.
View Article and Find Full Text PDFAndrographis paniculata plant extract is known to possess a variety of pharmacological activities. Andrographolide, the major constituent of the extract is implicated towards its pharmacological activity. We studied the cellular processes and targets modulated by andrographolide treatment in human cancer and immune cells.
View Article and Find Full Text PDFAzadirone 1, a limonoidal constituent of Azadirachta indica is found to possess potent cytotoxic activity against a panel of human cancer cell lines in our in vitro studies. In vitro screening of a number of semi-synthetic analogues of 1 revealed that the alpha,beta-unsaturated enone moiety or its equivalent conjugated system in A-ring, C-7 acetyloxy/chloroacetyloxy or keto group in B-ring and the furan moiety are responsible for the activity of 1 and its analogues. Compound 1 and two of the semi-synthetic analogues 10 and 13 were found to possess good in vivo antitumor activity in modified hollow fiber animal models.
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