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991.
A battery of performance tests consisting of 'letter cancellation,' 'hand 'precision,' 'two-hand coordination,' and 'tweezer dexterity' were administered on 12 desk workers in an illumination chamber under six different combinations of noise and illumination made out of two levels of white noise (70 and 100 dB) and three levels of illuminations (50, 150, and 300 lx). The objective was to find out the combined effects of noise and illumination on the performance efficiency of the above tests. A 6 x 6 latin square design was followed. A three-way analysis of variance reflected significant combined effects of noise and illumination on the accuracy scores of the letter cancellation test and hand precision test and the efficiency score of the latter test. Significant separate effects of noise were, however, observable on the speed scores and efficiency scores of the letter cancellation test and that of illumination on the speed scores of this test as also the accuracy scores of the tweezer dexterity test. Studies ascertaining the effects of heat stress in combination with noise and illumination on human performance efficiency have been suggested. 相似文献
992.
Summary Coleonol was produced in callus culture; the kind and level of phytohormones, glycine, casein hydrolysate and sucrose content of the medium differently influenced growth and product formation. Maximum specific growth rate was obtained in medium containing 7% sucrose. Biomass production was highest with 4 ppm of NAA. Maximum product (0.075% of dry cells) was formed in medium containing 0.5 ppm IAA and IBA each, 5 ppm glycine, 200 ppm casein hydrolysate and 7% sucrose.Abbreviations Su
Sucrose
- NAA
naphthalene acetic acid
- 2,4-D-2,4
diphenoxy acetic acid
- IBA
Indole-3-butyric acetic acid
- IAA
indole 3-acetic acid
- Kn
Kinetin
- Gl
glycine
- Ch
casein hydrolysate 相似文献
993.
S. Chandra Nayaka A.C. Uday Shankar S. Niranjan Raj M. S. Reddy H. S. Prakash 《Archives Of Phytopathology And Plant Protection》2013,46(3):264-282
Fusarium verticillioides is one of the most important fungal pathogens in maize causing both pre- and post-harvest losses and also capable of producing Fumonisins. In the present study attempts have been made for screening potential T. harzianum from native rhizosphere and to study its effect on Fusarium ear rot disease, fumonisin accumulation in different maize cultivars grown in India. Eight isolates of T. harzianum were isolated and T. harzianum isolate Th-8 exhibited better antifungal activity than carbendizim. Th-8 was formulated in different solid substrates like wheat bran, paddy husk, talcum powder and cornstarch. Maize seeds of kanchan (moderately resistant), pioneer (resistant) and sweet corn (susceptible) were selected for laboratory and field studies and these seeds were treated with a conidial suspension of T. harzianum at the rate of 1 × 108 spore/ml and formulation at the rate of 10 g/kg. Treated seeds were subjected to evaluate F. verticillioides incidence, seed germination, seedling vigour and field emergence, yield, thousand seed weight and fumonisin production. It was found that the pure culture of T. harzianum was more effective in reducing the F. verticillioides and fumonisin incidence followed by Talc formulation than the carbendizim treated and untreated control. Formulations of T. harzianum were effective at reducing the F. verticillioides and Fumonisin infection and also increasing the seed germination, vigour index, field emergence, yield, and thousand seed weight in comparison with the control. 相似文献
994.
995.
Shuvomoy Banerjee Jie Lu Qiliang Cai Zhiguo Sun Hem Chandra Jha Erle S. Robertson 《PLoS pathogens》2014,10(8)
Epstein–Barr virus (EBV), a ubiquitous human herpesvirus, can latently infect the human population. EBV is associated with several types of malignancies originating from lymphoid and epithelial cell types. EBV latent antigen 3C (EBNA3C) is essential for EBV-induced immortalization of B-cells. The Moloney murine leukemia provirus integration site (PIM-1), which encodes an oncogenic serine/threonine kinase, is linked to several cellular functions involving cell survival, proliferation, differentiation, and apoptosis. Notably, enhanced expression of Pim-1 kinase is associated with numerous hematological and non-hematological malignancies. A higher expression level of Pim-1 kinase is associated with EBV infection, suggesting a crucial role for Pim-1 in EBV-induced tumorigenesis. We now demonstrate a molecular mechanism which reveals a direct role for EBNA3C in enhancing Pim-1 expression in EBV-infected primary B-cells. We also showed that EBNA3C is physically associated with Pim-1 through its amino-terminal domain, and also forms a molecular complex in B-cells. EBNA3C can stabilize Pim-1 through abrogation of the proteasome/Ubiquitin pathway. Our results demonstrate that EBNA3C enhances Pim-1 mediated phosphorylation of p21 at the Thr145 residue. EBNA3C also facilitated the nuclear localization of Pim-1, and promoted EBV transformed cell proliferation by altering Pim-1 mediated regulation of the activity of the cell-cycle inhibitor p21/WAF1. Our study demonstrated that EBNA3C significantly induces Pim-1 mediated proteosomal degradation of p21. A significant reduction in cell proliferation of EBV-transformed LCLs was observed upon stable knockdown of Pim-1. This study describes a critical role for the oncoprotein Pim-1 in EBV-mediated oncogenesis, as well as provides novel insights into oncogenic kinase-targeted therapeutic intervention of EBV-associated cancers. 相似文献
996.
The present study was performed to investigate the possible role of carbon (C) and nitrogen (N) metabolism in adaptation of Indian mustard (Brassica juncea L.) growing under ambient (370 ± 15 ppm) and elevated CO2 (700 ± 15 ppm), and jointly in elevated CO2 and temperature (30/22 °C for day/night). The key enzymes responsible for C–N metabolism were studied in different samples of Brassica juncea L. collected from ambient (AMB), elevated (ELE) and ELExT growth conditions. Total percent amount of C and N in leaves were particularly estimated to establish a clear understanding of aforesaid metabolism in plant adaptation. Furthermore, key morphological and physiological parameters such as plant height, leaf area index, dry biomass, net photosynthetic rate, stomatal conductance, transpiration, total protein and chlorophyll contents were also studied in relation to C/N metabolism. The results indicated that the C-metabolizing enzymes, such as (ribulose-1,5-bisphosphate carboxylase/oxygenase, phosphoenolpyruvate carboxylase, malate dehydrogenase, NAD-malic enzyme, NADP-malic enzyme and citrate synthase) and the N-metabolizing enzymes, such as (aspartate amino transferase, glutamine synthetase, nitrate reductase and nitrite reductase) showed significantly (P < 0.05) higher activities along with the aforesaid physiological and biochemical parameters in order of ELE > ELExT > AMB growth conditions. This is also evident by significant (P < 0.05) increase in percent contents of C and N in leaves as per said order. These findings suggested that improved performance of C–N metabolism could be a possible approach for CO2 assimilation and adaptation in Brassica juncea L. against elevated CO2 and temperature prevailing in climate change scenarios. 相似文献
997.
Balawant Kumar Chakrapani Tripathi Ranjana K. Kanchan Jitendra Kumar Tripathi Jimut K. Ghosh Ravishankar Ramachandran Smrati Bhadauria Raj Kamal Tripathi 《PloS one》2013,8(6)
FasL mediated preferential apoptosis of bystander CTLs while protection of infected CD4+T cells remains one of the hallmarks of immune evasion during HIV infection. The property of infected host cells to evade cell-autonomous apoptosis emanates from ability of HIV-1Nef -protein to physically interact with ASK-1 and thereby inhibit its enzymatic activity. The specific domains of HIV-1Nef through which it may interact with ASK1 and thereby impair the ASK1 activity remain unidentified so far and represent a major challenge towards developing clear understanding about the dynamics of this interaction. Using mammalian two hybrid screen in association with site directed mutagenesis and competitive inhibitor peptides, we identified constituent minimal essential domain (152 DEVGEANN 159) through which HIV-1Nef interacts with ASK1 and inhibits its function. Furthermore our study also unravels a novel alternate mechanism underlying HIV-1 Nef mediated ASK1 functional modulation, wherein by potentiating the inhibitory ser967 phosphorylation of ASK1, HIV-1Nef negatively modulated ASK1function. 相似文献
998.
Suresh Kumar Amaresh Chandra Madan G. Gupta 《Journal of plant biochemistry and biotechnology.》2008,17(2):181-184
An efficient protocol has been developed for in vitro plant regeneration via multiple shoot induction in lucerne (Medicago sativa L). Shoot tips from in vitro grown 5–6 days old seedlings of 3 cultivars, LLC-3, Chetak and RL-88 were used as explants for multiple shoot induction on MS medium supplemented with cytokinins. Maximum of 14 shoots per apical meristem were observed in case of cv Chetak on MS medium supplemented with BAP (12.6 μM) and KN (9.3 μM). Shoot elongation on MS medium supplemented with GA (5.8 μM), while root induction was achieved on MS medium supplemented with IAA (11.4 μM) and activated charcoal (2.0 g l?1). Tissue raised plants showed 75% survival after transfer to soil under field conditions. 相似文献
999.
Present study was designed to examine daily and seasonal variability in the innate immune responses of splenocytes in the fresh water snake, Natrix piscator. Animals were mildly anesthetized and spleen was aseptically isolated and processed for macrophage phagocytosis, NBT reduction, nitrite production, splenocyte proliferation and serum lysozyme activity. Samples were collected at seven time points, viz., 0000, 0400, 0800, 1200, 1600, 2000 and 0000 h during three different seasons, namely summer, winter and spring. Cosinor analysis revealed that percent phagocytosis had a significant 24-h rhythm during summer and spring seasons. The peaks of rhythms in NBT reduction and nitrite release occurred in the morning hours at 10.88 h and 8.31 h, respectively, in winter. A significant 24-h rhythm was also observed in lysozyme concentration and splenocyte proliferation (both Basal and Concanavalin A stimulated) in all three seasons. A significant phase shift in splenocyte proliferation was obtained with a trend of delayed phase shift from winter to spring and from spring to summer. Of the nine variables, significant annual (seasonal) rhythms were detected in almost all variables, excluding phagocytic and splenosomatic indices. All rhythmic variables, except spleen cellularity, exhibited tightly synchronized peaks coinciding with the progressive and recrudescence phases of annual reproductive cycle. It is concluded that the snake synchronizes its daily and seasonal immune activity with the corresponding external time cues. The enhancement of immune function coinciding with one of its crucial reproductive phases might be helping it to cope with the seasonal stressors, including abundance of pathogens, which would otherwise jeopardize the successful reproduction and eventual survival of the species. 相似文献
1000.
Growing male rats were exposed to cadmium (Cd, 100 micrograms/kg, ip) for 51 days and the effect on the different components of locomotor behaviour was assessed on days 38, 46 and 51 of Cd exposure. Significant decrease in distance travelled, stereotypic time and movements, ambulatory time and vertical movements were observed in Cd-exposed rats, whereas the time of rest was increased. The number of entries into the inner as well as the outer squares and the total time spent in the inner squares of the floor area were significantly reduced. Results indicate that Cd exposure results in a general depression in all aspects of motor behaviour leading to decrease in gross locomotor activity. The involvement of an exaggerated emotional reactivity in the behavioural expression of the Cd-treated animals is also emphasized. 相似文献