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991.
Tantravahi Srinivasan Koppolu Raja Rajesh Kumar Pulugurtha Bharadwaja Kirti 《Plant Cell, Tissue and Organ Culture》2010,101(3):303-309
Though peanut tissue culture has advanced to a considerable extent using a number of explants with the subsequent production
of transgenic plants, wild Arachis species appeared to be recalcitrant to using similar explants. In this study, the use of cotyledonary nodes as explants prepared
from 7-day old seedlings resulted in the development of a simple and rapid regeneration protocol for five diploid wild species
including A. diogoi, A. stenosperma, A. duranensis, A. cardenasii and A. correntina belonging to the genus Arachis for producing multiple shoots. Shoot bud initiation was observed 10 to 15 days after culture initiation. Responding cotyledonary
nodes with shoot buds were subcultured to lower levels of cytokinin and finally to MS basal medium for further shoot development
and elongation. Production of multiple shoots was observed in all the five diploid species with a maximum of 9 to 16 shoots
were obtained per explant in the primary cultures. The number of shoot buds increased significantly with repeated explant
subculturing with recovery up to 45 shoots from responding explants. These shoots were rooted efficiently on MS medium supplemented
with 1 mg l−1 naphthalene acetic acid and the time taken from explanting to the transfer of shoots to potting mixture was about 12 weeks.
All rooted shoots were successfully established in soil in glass house and further transferred to field. These plants survived
to maturity and set seed. 相似文献
992.
Amber L. Annett Damien S. Carson Xavier Crosta Andrew Clarke Raja S. Ganeshram 《Polar Biology》2010,33(1):13-29
Phytoplankton assemblages from seasonally sea-ice covered Ryder Bay (Adelaide Island, Antarctica) were studied over three
austral summers (2004–2007), to link sea-ice variability and environmental conditions with algal speciation. Typical of near-shore
Antarctic waters, biomass was dominated by large diatoms, although the prymnesiophyte Phaeocystis antarctica was numerically dominant. Although there was considerable interannual variability between main diatom species, high biomass
of certain species or species groups corresponded consistently to certain phases of seasonal progression. We present the first
documentation of an extensive bloom of the late-season diatom Proboscia inermis in February 2006, accounting for over 90% of diatom biomass. At this time, water column stratification and nutrient drawdown
were high relative to other periods of the study, although carbon export was relatively low. Melt water flux in this region
promotes well-stratified surface waters and high chlorophyll levels, but not necessarily concurrent increases in export production
relative to seasons with lower freshwater inputs. 相似文献
993.
994.
995.
B. Raja Rao C. V. Damaraju Pro F. B. Raja Rao C. V. Damaraju 《Biometrical journal. Biometrische Zeitschrift》1992,34(8):919-935
It is well-known that the inequalities used in the definition of the New Better than Used (N. B. U.) and the New Better than Used in Expectation (N.B.U.E.) concepts, see BARLOW and PROSCHAN (1965, 1975) become equalities if, and only if, the life length of an organism follows an exponential distribution. It is proved in the present paper that these inequalities also reduce to equalities for the class of life distributions that have the “setting the clock back to zero” property. Simple examples of these distributions include the exponential, the linear hazard exponential and the Gompertz distributions. The General Krane distributions (Krane 1963) belong to this class, as well as a recent model introduced by CHIANG and CONFORTI (1989) of a survival distribution in which the hazard rate is a function of the accumulated effect of an individual's continuous exposure to the toxic material in the environment and his biological reaction to the toxin absorbed. As a simple application of the result proved in the paper, the life expectancy of an organism at age γ0 involved in the N.B.U.E. concept is evaluated for the Gompertzian growth process and for the Chiang and Conforti model. 相似文献
996.
Determinants of muscle power and force as assessed by Jumping Mechanography in rural Indian children
Sonal Kasture Raja Padidela Rainer Rawer Veena Ekbote Ketan Gondhalekar Vaman Khadilkar Anuradha Khadilkar 《Journal of musculoskeletal & neuronal interactions》2022,22(1):43
Objectives:To: 1. Assess muscle function (MF) of rural Indian children (6-11y, n=232), using Jumping Mechanography (JM) and hand dynamometer, 2. Investigate gender differences, 3. Identify determinants of MF.Methods:Data on anthropometry, muscle mass%, diet, physical activity, sunlight exposure, MF (maximum relative power Pmax/mass, maximum relative force Fmax/BW by JM; relative grip strength (RGS) by hand dynamometer) were collected. Pearson’s correlation and hierarchical linear regression was performed.Results:Pmax/mass, Fmax/BW and RGS of the group were 31.7±5.0W/kg, 3.0±0.3 and 0.4±0.1 (mean±SD), respectively. The Pmax/mass Z-score was –1.1±0.9 and Fmax/BW Z-score was –0.9±1 (mean±SD) which was significantly lower than the machine reference data (p<0.05). Positive association of muscle mass% and protein intake was observed with all MF parameters and moderate+vigorous physical activity with Fmax/BW (p<0.05). Determinants of MF identified through regression for Pmax/mass were age (β=1.83,95% CI=0.973 – 2.686), muscle mass% (β=0.244,95% CI=0.131–0.358) and protein intake (β=3.211,95% CI=1.597–4.825) and for Fmax/BW was protein intake (β=0.130,95% CI=0.023–0.237) (p<0.05). Male gender was a positive predictor of having higher Pmax/mass (β=1.707,95% CI=0.040–3.373) (p<0.05).Conclusion:MF was lower than in western counterparts. To optimize MF of rural Indian children, focus should be on improving muscle mass, ensuring adequate dietary protein, and increasing physical activity, especially in girls. 相似文献
997.
998.
The pancreas in the marine lizard fish Saurida tumbil (Bloch) encircles the pyloric region of the gastro-intestinal canal. The islets of Langerhans are ovoidal usually with a central cluster of β cells and the α cells in the periphery. In contrast to the β cells, the α cells have larger nuclei. Saurida tumbil is heavily parasitized by cestodes, nematodes and trematodes which infect the pancreas displacing or replacing much of the tissue. 相似文献
999.
Ryosuke Shirasaki Geoffrey M. Matthews Sara Gandolfi Ricardo de Matos Simoes Dennis L. Buckley Joseline Raja Vora Quinlan L. Sievers Johanna B. Brüggenthies Olga Dashevsky Haley Poarch Huihui Tang Megan A. Bariteau Michal Sheffer Yiguo Hu Sondra L. Downey-Kopyscinski Paul J. Hengeveld Brian J. Glassner Eugen Dhimolea Constantine S. Mitsiades 《Cell reports》2021,34(1):108532
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1000.
Segmentation of Extrapulmonary Tuberculosis Infection Using Modified Automatic Seeded Region Growing
Iman Avazpour M. Iqbal Saripan Abdul Jalil Nordin Raja Syamsul Azmir Raja Abdullah 《Biological procedures online》2009,11(1):241-252
In the image segmentation process of positron emission tomography combined with computed tomography (PET/CT) imaging, previous
works used information in CT only for segmenting the image without utilizing the information that can be provided by PET.
This paper proposes to utilize the hot spot values in PET to guide the segmentation in CT, in automatic image segmentation
using seeded region growing (SRG) technique. This automatic segmentation routine can be used as part of automatic diagnostic
tools. In addition to the original initial seed selection using hot spot values in PET, this paper also introduces a new SRG
growing criterion, the sliding windows. Fourteen images of patients having extrapulmonary tuberculosis have been examined
using the above-mentioned method. To evaluate the performance of the modified SRG, three fidelity criteria are measured: percentage
of under-segmentation area, percentage of over-segmentation area, and average time consumption. In terms of the under-segmentation
percentage, SRG with average of the region growing criterion shows the least error percentage (51.85%). Meanwhile, SRG with
local averaging and variance yielded the best results (2.67%) for the over-segmentation percentage. In terms of the time complexity,
the modified SRG with local averaging and variance growing criterion shows the best performance with 5.273 s average execution
time. The results indicate that the proposed methods yield fairly good performance in terms of the over- and under-segmentation
area. The results also demonstrated that the hot spot values in PET can be used to guide the automatic segmentation in CT
image. 相似文献