197 research outputs found

    Experimental evaluation of active and passive means of alleviating rotor impulsive noise in descent flight

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    A controlled wind tunnel test program was conducted on a model 2.14 m (7 ft) diameter teetering rotor to determine the effectiveness of blade tips such as the Ogee tip and the TAMI (Tip Air Mass Injection) tip in reducing the impulsive noise due to blade-vortex interaction in descent flight. In addition, a full rectangular tip which has the same span as the Ogee tip and an effective rectangular tip which has the same lifting area as the Ogee tip were also considered. The tests were conducted at two advance ratios (0.125 and 0.14) with various descent rates ranging from steady level flight to about 6 m/sec (20 ft/sec). A comparison of the performance of different rotors showed that for the same tip Mach number and thrust, the Ogee tip rotor absorbed more power than the full rectangular tip rotor, while the TAMI tip rotor absorbed more power than the effective tip rotor

    Occurrence of concurrent infections with multiple viruses in Penaeus monodon from culture ponds of north coastal Andhra Pradesh

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    A histopathological study of Penaeus monodon show-ing external symptoms of white spot disease, collected from culture ponds at Mulakuddu and Rambilli villages (Visakhapatnam District) during May and July 2001, provided evidence for the occurrence of multiple viral infections. Each diseased shrimp carried concurrent infections with four different viruses, identified on the basis of nuclear changes, resulting in the formation of characteristic inclusion/occlusion bodies, as WSSV, YHV, MBV and IHHNV. The iden-tification of the various viruses needs confirmation through molecular diagnostic methods. This consti-tutes a report recording concurrent infections with multiple viruses in a single shrimp

    Breeding and genetic diversity in Chrysanthemum morifolium in India : A review

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    Genetic diversity of any crop plays a very important role in developing new and novel desired forms through breeding and selection. Knowledge of diversity and its response to natural/human selection through hybridization is necessary for future breeding plan. All the present day colourful varieties of Chrysanthemum morifolium Ramat have been developed through complex interspecific crosses among elemental species, open pollination, indiscriminate intervarietal hybridization, spontaneous and induced mutation, selection and management of chimera. In floriculture industry there is always demand and necessity for new varieties. There is an urgent need for developing crop wise database. There is no record of total chrysanthemum varieties developed through classical breeding in different countries. Present article will provide maximum information generated in India on classical and mutation breeding on chrysanthemum along with important publications in chrysanthemum/floriculture by other research institutions/ universities

    Microstrip Line Fed Leaky Wave Antenna with Shorting Vias for Wideband Systems

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    In this work a complex structured shorted vias microstrip leaky wave antenna is designed and analysed. A Leaky wave antenna is a travelling wave structure with complex propagation constant. When shorting vias are loaded in a periodic structure the fundamental resonant mode shows some stop band characteristics and some of the modes will strongly attenuated. Three different types of iterations are examined in this work with and without defected ground structures. The defected ground structure based leaky wave antennas are showing better performance characteristics with respect to efficiency and phase. A micro strip line feeding with impedance of 50 ohms at both ports are providing excellent impedance matching to the conducting path on the microstrip surface. The shorting vias are suppressing certain higher order frequency bands and providing excellent wide band characteristics with low loss

    Determination of genetic variation for vegetative and floral traits in African marigold (Tagetes erecta)

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    Twenty-one genotypes of African marigold were (Tagetes erecta L.) evaluated for 11 growth and flowering related traits to study their genetic parameters such as variability, heritability, genetic (GCV), phenotypic (PCV) coefficient of variation and correlation and path coefficient analysis. Analysis of variance for all the traits showed significant differences among genotypes for all the growth and flowering related traits. High range in mean performance has been observed for traits, viz. plant height (64.00-106.67 cm), plant spread (49.33-72.00 cm), flower diameter (3.77- 6.17 cm), days required for flowering (78.67-99.33 days), number of secondary branches (22.13-37.47) and flower duration (26.00-44.83 days). Higher genotypic and phenotypic coefficient of variation was observed for traits such as fresh flower weight per plant, flower fresh weight per 10 flowers, number of flowers per plant, stem girth, flowering duration, etc. The high value (> 90%) of heritability was observed for all traits except plant height, plant spread and stem girth. The genetic advance was found ranged from 1.23 for flower diameter to 288.69 for fresh flower weight per plant. High values of genetic advance as per cent of mean was recorded for number of flowers (59.79%) followed by fresh flower weight per plant (59.32%) and flower fresh weight per 10 flowers (58.09%). Fresh flower weight per plant is significantly and positively correlated both at genotypic and phenotypic level for plant spread, flower fresh weight per flower, number of flowers per plant and flower diameter. Path coefficient analysis at genotypic level revealed that the number of primary branches per plant contributed highest and has significantly positive direct effect on fresh flower weight per plant followed by number of flowers per plant, flower diameter, flower fresh weight per flower, days required for flowering and stem girth. The different genotypes were identified to be performing differently for different quantitative traits. Hence, those genotypes with superior traits could be involved in the hybridization programme for assembling of desirable traits in a single genotype

    Effect of shade levels on production and quality of cordyline (Cordyline terminalis)

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    An investigation was carried out during 2013-14 to study the effect of different shade levels on the production and quality of cordyline (Cordyline terminalis Kunth.) under the subtropical condition of New Delhi, India. The effect of spectral control of light on physiology and vegetative development was evaluated at different crop growth stages. Shade nets did not only protect plants from high light intensities but also improved the vegetative growth, yield, vase life and quality of cordyline cut greens irrespective of shade level. Different shade levels modified microclimates, PAR, transmittance and canopy temperature. The shading improved plant characters like height, number of leaves, chlorophyll content, leaf area, fresh weight, harvest index and vase life. The plants grown under different shade levels showed improved photosynthetic activity and reduced transpiration rate. Plants grown under 50% shade level were taller, along with more number of leaves having longer petiole, chlorophyll content which can be attributed to higher photosynthetic rate, whereas harvest index and vase life was optimum. Overall, shade net with 50% shading was found best for commercial production of cordyline cut greens

    Microbial Co-Infection Alters Macrophage Polarization, Phagosomal Escape, and Microbial Killing

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    Macrophages are important innate immune cells that respond to microbial insults. In response to multi-bacterial infection, the macrophage activation state may change upon exposure to nascent mediators, which results in different bacterial killing mechanism(s). In this study, we utilized two respiratory bacterial pathogens, Mycobacterium bovis (Bacillus Calmette Guẻrin, BCG) and Francisella tularensis live vaccine strain (LVS) with different phagocyte evasion mechanisms, as model microbes to assess the influence of initial bacterial infection on the macrophage response to secondary infection. Non-activated (M0) macrophages or activated M2-polarized cells (J774 cells transfected with the mouse IL-4 gene) were first infected with BCG for 24–48 h, subsequently challenged with LVS, and the results of inhibition of LVS replication in the macrophages was assessed. BCG infection in M0 macrophages activated TLR2-MyD88 and Mincle-CARD9 signaling pathways, stimulating nitric oxide (NO) production and enhanced killing of LVS. BCG infection had little effect on LVS escape from phagosomes into the cytosol in M0 macrophages. In contrast, M2-polarized macrophages exhibited enhanced endosomal acidification, as well as inhibiting LVS replication. Pre-infection with BCG did not induce NO production and thus did not further reduce LVS replication. This study provides a model for studies of the complexity of macrophage activation in response to multi-bacterial infection

    A comparison of clinical outcomes between vaccinated and vaccine-naive patients of COVID-19, in four tertiary care hospitals of Kerala, South India

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    The problem considered: This multi-centric study analyzed data of COVID-19 patients and compared differences in symptomatology, management, and outcomes between vaccinated and vaccine-naive patients. Methods: All COVID-19 positive individuals treated as an in-or out-patient from the 1stMarch to 15th May 2021 in four selected study sites were considered for the study. Treatment details, symptoms, and clinical course were obtained from hospital records. Chi-square was used to test the association of socio-demographic and treatment variables with the vaccination status and binary logistic regression were used to obtain the odds ratio with a 95% confidence interval. Results: The analysis was of 1446 patients after exclusion of 156 with missing data of which males were 57.3% and females 42.7%. 346 were vaccinated; 189 received one dose and 157 both doses. Hospitalization was more in vaccinated (38.2% vs 27.4%); ICU admissions were less in vaccinated (3.5% vs 7.1%). More vaccinated were symptomatic (OR = 1.5); half less likely to be on non-invasive ventilation (OR = 0.5) while vaccine naive patients had 4.21 times the risk of death. Conclusion: Severe infection, duration of hospital stays, need for ventilation and death were significantly less among vaccinated when compared with vaccine naive patients

    High-level characteristics of or-and independent and-parallelism in prolog

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    Although studies of a number of parallel implementations of logic programming languages are now available, their results are difficult to interpret due to the multiplicity of factors involved, the effect of each of which is difficult to sepárate. In this paper we present the results of a high-level simulation study of or- and independent and-parallelism with a wide selection of Prolog programs that aims to determine the intrinsic amount of parallelism, independently of implementation factors, thus facilitating this separation. We expect this study will be instrumental in better understanding and comparing results from actual implementations, as shown by some examples provided in the paper. In addition, the paper examines some of the issues and tradeoffs associated with the combination of and- and or-parallelism and proposes reasonable solutions based on the simulation data obtained

    Raloxifene inhibits tumor growth and lymph node metastasis in a xenograft model of metastatic mammary cancer

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    <p>Abstract</p> <p>Background</p> <p>The effects of raloxifene, a novel selective estrogen receptor modulator, were studied in a mouse metastatic mammary cancer model expressing cytoplasmic ERα.</p> <p>Methods</p> <p>Mammary tumors, induced by inoculation of syngeneic BALB/c mice with BJMC3879luc2 cells, were subsequently treated with raloxifene at 0, 18 and 27 mg/kg/day using mini-osmotic pumps.</p> <p>Results</p> <p><it>In vitro </it>study demonstrated that the ERα in BJMC3879luc2 cells was smaller (between 50 and 64 kDa) than the normal-sized ERα (66 kDa) and showed cytoplasmic localization. A statistically significant but weak estradiol response was observed in this cell line. When BJMC3879luc2 tumors were implanted into mice, the ERα mRNA levels were significantly higher in females than in males. <it>In vitro </it>studies showed that raloxifene induced mitochondria-mediated apoptosis and cell-cycle arrest in the G1-phase and a decrease in the cell population in the S-phase. In animal experiments, tumor volumes were significantly suppressed in the raloxifene-treated groups. The multiplicity of lymph node metastasis was significantly decreased in the 27 mg/kg group. Levels of apoptosis were significantly increased in the raloxifene-treated groups, whereas the levels of DNA synthesis were significantly decreased in these groups. No differences in microvessel density in tumors were observed between the control and raloxifene-treated groups. The numbers of dilated lymphatic vessels containing intraluminal tumor cells were significantly reduced in mammary tumors in the raloxifene-treated groups. The levels of ERα mRNA in mammary tumors tended to be decreased in the raloxifene-treated groups.</p> <p>Conclusion</p> <p>These results suggest that the antimetastatic activity of raloxifene in mammary cancer expressing cytoplasmic ERα may be a crucial finding with clinical applications and that raloxifene may be useful as an adjuvant therapy and for the chemoprevention of breast cancer development.</p
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