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111.
112.
CaS:Ce3+ is an efficient green‐emitting (535 nm) phosphor, excitable with blue light (450–470 nm) and was synthesized via a solid‐state reaction method by heating under a reducing atmosphere. The luminescent properties, photoluminescent (PL) excitation and emission of the phosphor were analyzed by spectrofluorophotometry. The excitation and emission peaks of the CaS:Ce3+ phosphor lay in the visible region, which made them relevant for light‐emitting diode (LED) application for the generation of white light. Judd‐Oflet parameters were calculated and revealed that green light emitted upon blue illumination. The prepared phosphor had strong blue absorption at 470 nm and a broad green emission band range from 490–590 nm with the peak at 537 nm. The characteristics of the CaS:Ce3+ phosphor make it suitable for use as a wavelength tunable green emitting phosphor for three band white LEDs pumped by a blue LED (470 nm). The Commission International de l'Eclairage co‐ordinates were calculated by a spectrophotometric method using the spectral energy distribution (0.304, 0.526) and confirm the green emission. The potential application of this phosphor is as a phosphor‐converted white light‐emitting diode. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
113.
V.M. Katoch N Saxena C.T. Shivannavar V.D. Sharma K Katoch R.K. Sharma P Suryanarayana Murthy 《FEMS immunology and medical microbiology》1998,20(2):99-102
The effect of trifluoperazine (TFP), a calmodulin antagonist, was investigated on in vitro ATP levels of human derived Mycobacterium leprae . M. leprae were obtained from biopsies from multi-bacillary forms of leprosy and were incubated in a modified Dubos medium system which supports limited in vitro synthesis of M. leprae . This incubation was carried out in the absence and presence of different concentrations of trifluoperazine. Samples for estimation of bacillary ATP levels were taken at day 0 and at 14 days of incubation. TFP inhibited ATP levels in M. leprae and this inhibitory effect was marginal at 2.5 μg ml−1 (35% inhibition), highly significant at 5 μg ml−1 (87% inhibition) and almost total at 10 μg ml−1 (98.5% inhibition). This compound appears to have potential as an anti-leprotic drug and also as a broad spectrum anti-mycobacterial agent in view of its anti-tubercular activity reported earlier. 相似文献
114.
Kawai Y Puma SC Hargens AR Murthy G Warkander D Lundgren CE 《Journal of gravitational physiology : a journal of the International Society for Gravitational Physiology》1997,4(3):31-34
Cerebral blood flow (CBF) velocity and cranial fluid volume, which is defined as the total volume of intra- and extracranial fluid, were measured using transcranial Doppler ultrasonography and rheoencephalography, respectively, in humans during graded increase of +Gz acceleration (onset rate: 0.1 G/s) without straining maneuvers. Gz acceleration was terminated when subjects' vision decreased to an angle of less than or equal to 60 degrees, which was defined as the physiological end point. In five subjects, mean CBF velocity decreased 48% from a baseline value of 59.4 +/- 11.2 cm/s to 31.0 +/- 5.6 cm/s (p<0.01) with initial loss of peripheral vision at 5.7 +/- 0.9 Gz. On the other hand, systolic CBF velocity did not change significantly during increasing +Gz acceleration. Cranial impedance, which is proportional to loss of cranial fluid volume, increased by 2.0 +/- 0.8% above the baseline value at the physiological end point (p<0.05). Both the decrease of CBF velocity and the increase of cranial impedance correlated significantly with Gz. These results suggest that +Gz acceleration without straining maneuvers decreases CBF velocity to half normal and probably causes a caudal fluid shift from both intra- and extracranial tissues. 相似文献
115.
Yun-soo Kim Eun-joo Hahn Hosakatte Niranjana Murthy Kee-yoeup Paek 《Biotechnology letters》2005,26(21):1619-1622
Adventitious roots of ginseng were treated with methyl jasmonate (MJ) up to 150m and cultured for 40days. Up to 100m MJ inhibited the root growth but increase ginsenoside accumulation. In a two-stage bioreactor culture, total ginsenosides, after elicitation with 100 m MJ peaked after 10days at 48mgg–1 dry wt and then dropped sharply. Of the two groups of ginsenosides (Rb and Rg), higher amounts of Rb accumulated in the adventitious roots.Revisions requested; 2 July 2004; Revisions received 30 June 2004; 3 September 2004 相似文献
116.
Murthy S. D. S.; Sabat Surendra Chandra; Mohanty Prasanna 《Plant & cell physiology》1989,30(8):1153-1157
Addition of low concentrations of mercury chloride (HgCl2 tointact cells of the cyanobacterium, Spirulina platensis causedan enhancement in the intensity of fluorescence emitted fromphycocyanin at room temperature and induced blue shifts in theemission peak suggestive of changes in energy transfer withinthe phycobilisomes. HgCl2 also suppressed the whole-chain electrontransport activity (H2O methylviologen) at much lower concentrationsthan that required to inhibit Hill activity supported by para-benzoquinone.The extent of inhibition of Hill activity was much higher underhigh-intensity light than that under low-intensity light. Ourresults indicate that mercury ions at low concentrations affectthe transfer of energy within phycobilisomes and at high concentrationsthey inhibit electron transport in this cyanobacterium. (Received February 21, 1989; Accepted October 2, 1989) 相似文献
117.
Rice (IR 42) was grown on two soils differing in zinc status for 30 days with and without Zn under submerged conditions in
pots. The fate of soil zinc was characterized by extraction of the soil successively with copper acetate and sodium hypochlorite
and by EUF extraction. Most of the applied zinc was extracted by copper acetate and represented as complexed fraction. There
exists a close and significnat relation between Cu(OAc)2-extractable zinc and Zn extracted by EUF for 5 minutes at 50 volts (r=0.98). The EUF-extractable zinc and Cu(OAc)2-extractable zinc were significantly correlated with the zinc content in the plant (r=0.82). The data from this investigation
suggest the possibility of Zn fractionation with the EUF technique and the fractions obtained agree closely to those determined
by chemical methods. The results obtained indicate that Zn in soil is held by weak organic bonding and that the extractions
by Cu(OAc)2 and/or EUF-5 minutes serve as a useful basis for extimating zinc availability in rice soils. 相似文献
118.
OBJECTIVE: To determine the clinical value of repeat fine needle aspiration (FNA) as a follow-up strategy in the management of patients in India, clinically suspected of having tuberculosis (TB) but showing a cytologic picture of acute suppuration. STUDY DESIGN: Repeat aspirates from 263 patients presenting with lymph node or soft tissue masses were analyzed. The previous FNA of these cases had shown acute inflammatory exudate but no epithelioid granuloma or acid-fast bacilli (AFB). RESULTS: The repeat FNA helped to detect 55% additional cases of TB within a period of 8 weeks; 67% of them were diagnosed in the second and third weeks. Diagnostic yield rose to 59% after the third FNA. AFB were detected in 34 (13.3%) cases that showed a low bacterial load. In addition, nontubercular lesions, such as epidermal inclusion cyst (4), cysticercosis (3), sialadenitis (2) and metastatic carcinoma (8), were diagnosed. CONCLUSION: All cases showing acute suppuration without granulomas or AFB on the first FNA should be reevaluated by follow-up FNA and staining for AFB. This will enhance the diagnostic yield of tuberculosis in developing countries, where molecular diagnostics are too costly or unavailable. This procedure is cost effective as compared to biopsy and culture. In addition to tuberculosis, many unexpected nontubercular lesions may also be unmasked. Repeat FNA reduces sampling and screening errors, improves sensitivity and helps to study the evolution of epithelioid granulomas. 相似文献
119.
Li Sui John C Warren Janelle PN Russell Nina V Stourman 《International Journal of Biochemistry and Molecular Biology》2012,3(3):302-312
Protein function prediction is very important in establishing the roles of various proteins in bacteria; however, some proteins in the E. coli genome have their function assigned based on low percent sequence homology that does not provide reliable assignments. We have made an attempt to verify the prediction that E. coli genes ygiC and yjfC encode proteins with the same function as glutathionylspermidine synthetase/amidase (GspSA). GspSA is a bifunctional enzyme that catalyzes the ATP-dependent formation and hydrolysis of glutathionylspermidine (G-Sp), a conjugate of glutathione (GSH) and spermidine. YgiC and YjfC proteins show 51% identity between themselves and 28% identity to the synthetase domain of the GspSA enzyme. YgiC and YjfC proteins were expressed and purified, and the properties of GspSA, YgiC, and YjfC were compared. In contrast to GspSA, proteins YgiC and YjfC did not bind to G-Sp immobilized on the affinity matrix. We demonstrated that all three proteins (GspSA, YgiC and YjfC) catalyze the hydrolysis of ATP; however, YgiC and YjfC cannot synthesize G-Sp, GSH, or GSH intermediates. gsp, ygiC, and yjfC genes were eliminated from the E. coli genome to test the ability of mutant strains to synthesize G-Sp conjugate. E. coli cells deficient in GspSA do not produce G-Sp while synthesis of the conjugate is not affected in ΔygiC and ΔyjfC mutants. All together our results indicate that YgiC and YjfC are not glutathionylspermidine synthetases as predicted from the amino acid sequence analysis. 相似文献
120.