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991.
A simple and rapid method for multiple shoot formation in vitro from immature embryo axis explants of Carica papaya L. cvs. Honey Dew, Washington and Co2 is described. Multiple shoot regeneration was achieved by culture of the explants on
modified Murashige and Skoog (MS) medium supplemented either with thidiazuron (TDZ; 0.45–22.7 μM) or a combination of benzylaminopurine
(BAP; 0.2 – 8.84 μM) and naphthalene acetic acid (NAA; 0.5 – 2.64 μM). Highest frequency of shoot regeneration occurred on
medium supplemented either with 2.25 μM TDZ or a combination of BAP (4.4 μM) and NAA (0.5 μM). Composition of the basal media
influenced the frequency of multiple shoot initiation. Stunted shoots regenerated at 4.5 μM and higher concentrations of TDZ.
Such shoots could, however, be elongated by transfer to medium containing 5.7 μM GA3. Rooting of the regenerated shoots was achieved in presence of indolebutyric acid (IBA; 4.92 – 19.68 μM), however, least
response was in presence of 14.7 μM IBA. Rooted plants were hardened and transferred to pots.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
992.
993.
994.
Rajasri Bhattacharyya Aparna Asokan Prodyut Bhattacharya Ram Prasad 《Biodiversity and Conservation》2009,18(13):3441-3451
Medicinal and aromatic plants (MAPs) are an integral part of our biodiversity. In majority of MAP rich countries, wild collection
practices are the livelihood options for a large number of rural peoples and MAPs play a significant role in socio-economic
development of their communities. Recent concern over the alarming situation of the status of wild MAP resources, raw material
quality, as well as social exploitation of rural communities, leads to the idea of certification for MAP resource conservation
and management. On one hand, while MAP certification addresses environmental, social and economic perspectives of MAP resources,
on the other hand, it ensures multi-stakeholder participation in improvement of the MAP sector. This paper presents an overview
of MAP certification encompassing its different parameters, current scenario (Indian background), implementation strategies
as well as stakeholders’ role in MAP conservation. It also highlights Indian initiatives in this direction. 相似文献
995.
Joydeep Bhattacharya 《PloS one》2009,4(1)
Background
Different complex systems behave in a similar way near their critical points of phase transitions which leads to an emergence of a universal scaling behaviour. Universality indirectly implies a long-range correlation between constituent subsystems. As the distributed correlated processing is a hallmark of higher complex cognition, I investigated a measure of universality in human brain during perception and mental imagery of complex real-life visual object like visual art.Methodology/Principal Findings
A new method was presented to estimate the strength of hidden universal structure in a multivariate data set. In this study, I investigated this method in the electrical activities (electroencephalogram signals) of human brain during complex cognition. Two broad groups - artists and non-artists - were studied during the encoding (perception) and retrieval (mental imagery) phases of actual paintings. Universal structure was found to be stronger in visual imagery than in visual perception, and this difference was stronger in artists than in non-artists. Further, this effect was found to be largest in the theta band oscillations and over the prefrontal regions bilaterally.Conclusions/Significance
Phase transition like dynamics was observed in the electrical activities of human brain during complex cognitive processing, and closeness to phase transition was higher in mental imagery than in real perception. Further, the effect of long-term training on the universal scaling was also demonstrated. 相似文献996.
Biomimetic Spider‐Web‐Like Composites for Enhanced Rate Capability and Cycle Life of Lithium Ion Battery Anodes 下载免费PDF全文
Pallab Bhattacharya Manikantan Kota Dong Hoon Suh Kwang Chul Roh Ho Seok Park 《Liver Transplantation》2017,7(17)
It is crucial to control the structure and composition of composite anode materials to enhance the cell performance of such anode materials for lithium ion batteries. Herein, a biomimetic strategy is demonstrated for the design of high performance anode materials, inspired by the structural characteristics and working principles of sticky spider‐webs. Hierarchically porous, sticky, spider‐web‐like multiwall carbon nanotube (MWCNT) networks are prepared through a process involving ozonation, ice‐templating assembly, and thermal treatment, thereby integrating the networks with γ‐Fe2O3 particles. The spider‐web‐like MWCNT/γ‐Fe2O3 composite network not only traps the active γ‐Fe2O3 materials tightly but also provides fast charge transport through the 3D internetworked pathways and the mechanical integrity. Consequently, the composite web shows a high capacity of ≈822 mA h g?1 at 0.05 A g?1, fast rate capability with ≈72.3% retention at rates from 0.05 to 1 A g?1, and excellent cycling stability of >88% capacity retention after 310 cycles with a Coulombic efficiency >99%. These remarkable electrochemical performances are attributed to the complementarity of the 3D spider‐web‐like structure with the strong attachment of γ‐Fe2O3 particles on the sticky surface. This synthetic strategy offers an environmentally safe, simple, and cost‐effective avenue for the biomimetic design of high performance energy storage materials. 相似文献
997.
Ravi Bharadwaj Ranjana Arya M. Shahid mansuri Sudha Bhattacharya Alok Bhattacharya 《Cellular microbiology》2017,19(10)
The protozoan parasite Entamoeba histolytica causes amoebiasis, a major public health problem in developing countries. Motility of E. histolytica is important for its pathogenesis. Blebbing is an essential process contributing to cellular motility in many systems. In mammalian cells, formation of plasma membrane blebs is regulated by Rho‐GTPases through its effectors, such as Rho kinase, mDia1, and acto‐myosin proteins. In this study, we have illuminated the role of EhRho1 in bleb formation and motility of E. histolytica. EhRho1 was found at the site of bleb formation in plasma membrane of trophozoites. Overexpression of mutant EhRho1 defective for Guanosine triphosphate (GTP)‐binding or down‐regulating EhRho1 by antisense RNA resulted in reduced blebbing and motility. Moreover, serum‐starvation reduced blebbing that was restored on serum‐replenishment. Lysophosphatidic acid treatment induced bleb formation, whereas wortmannin inhibited the process. In all these cases, concentration of GTP‐EhRho1 (active) and Phosphatidylinositol 4,5‐bisphosphate (PIP2) inversely correlated with the level of plasma membrane blebbing. Our study suggests the role of EhRho1 in blebbing and bleb‐based motility through PI3 kinase pathway in E. histolytica. 相似文献
998.
The present study displays the biodegradation capacities of native bacteria toward polycyclic aromatic hydrocarbons with particular emphasis to anthracene. A total of 23 bacterial strains were isolated from hydrocarbon-contaminated sites of Guwahati city, using anthracene as the carbon source. Among all these isolates, one Gram-positive strain (JMG-01) was selected as an efficient anthracene degrader, based on its maximum growth ability in anthracene enriched medium (100 ppm–700 ppm). At 500 ppm concentration, strain JMG-01 showed the maximum growth rate with 98% of anthracene degradation within 21 days of observation. The strain also demonstrated its potentiality by utilizing naphthalene and higher molecular hydrocarbons like pyrene, and benzo(a)pyrene at 500 ppm. The morphological, biochemical and molecular characterization identified the strain as Bacillus cereus. Surface morphology of the biomass, captured by Atomic Force Microscope, showed a distinctive modification, during the process of degradation. Study revealed that the effect of hydrocarbon exhibited the alteration, which concurrently enhanced the metabolic activity. Further, Gas chromatography-mass spectrometer analysis elucidates the possible metabolic pathway of anthracene degradation, depending on the intermediate metabolites produced. The finding thus suggests the essence of Bacillus cereus strain JMG-01 in enhanced anthracene degradation along the utilization of other hydrocarbons. 相似文献
999.
Naresh Vasupalli Mahesh Rao Rohit Chamola Usha Pant Ramcharan Bhattacharya Shripad Ramachandra Bhat 《Molecular breeding : new strategies in plant improvement》2017,37(9):110
Alien introgressions into crop plants rely on phenotypic evaluation. Employing molecular markers could greatly accelerate this and help discover new alleles/QTLs. We report here a new strategy to develop markers for tracking introgression using genome survey sequence. We demonstrate this using an advanced backcross population of Brassica juncea involving the wild species Diplotaxis erucoides. To develop D. erucoides-specific markers, 72 million single end reads were obtained using Ion-Torrent platform. Quality reads (67.6 million) were checked against Brassica database and the redundant reads were eliminated. De novo assembly of the remaining 14.6 million reads gave 3895 contigs (> 1 kb), which were used to design 101 donor-specific (DS) STS markers. Of these, 89 markers showed polymorphism between D. erucoides and B. juncea. Genotyping of 90 randomly picked plants with 31 donor-specific STS markers detected 22 plants containing 17 markers. Alien introgression was also detected in eight of the 22 lines displaying phenotypes deviating from B. juncea parent. The marker DSSTS 70 was found in six of the nine lines showing glossy leaf suggesting its association with the trait. This is the first study demonstrating the use of molecular markers for implementing reverse genetics approach for alien introgression into crop plants. 相似文献
1000.
Using complementary approaches to identify trans‐domain nuclear gene transfers in the extremophile Galdieria sulphuraria (Rhodophyta) 下载免费PDF全文
Ravi S. Pandey Garima Saxena Debashish Bhattacharya Huan Qiu Rajeev K. Azad 《Journal of phycology》2017,53(1):7-11
Identification of horizontal gene transfers (HGTs) has primarily relied on phylogenetic tree based methods, which require a rich sampling of sequenced genomes to ensure a reliable inference. Because the success of phylogenetic approaches depends on the breadth and depth of the database, researchers usually apply stringent filters to detect only the most likely gene transfers in the genomes of interest. One such study focused on a highly conservative estimate of trans‐domain gene transfers in the extremophile eukaryote, Galdieria sulphuraria (Galdieri) Merola (Rhodophyta), by applying multiple filters in their phylogenetic pipeline. This led to the identification of 75 inter‐domain acquisitions from Bacteria or Archaea. Because of the evolutionary, ecological, and potential biotechnological significance of foreign genes in algae, alternative approaches and pipelines complementing phylogenetics are needed for a more comprehensive assessment of HGT. We present here a novel pipeline that uncovered 17 novel foreign genes of prokaryotic origin in G. sulphuraria, results that are supported by multiple lines of evidence including composition‐based, comparative data, and phylogenetics. These genes encode a variety of potentially adaptive functions, from metabolite transport to DNA repair. 相似文献