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81.
Govindaraj S Kumari BD Cioni PL Flamini G 《Journal of Bioscience and Bioengineering》2008,105(3):176-183
Artemisia vulgaris L. (Mugwort) is a threatened and valuable medicinal plant. Attempts have been made in this research to mass propagate its plantlets through in vitro liquid culture technology using Murashige and Skoog (MS) basal medium supplemented with 6-benzyl adenine (BA) (0.44-8.88 microM). Initially, 22.6 shoots (99.9% shooting frequency) developed from shoot tip explants cultured in MS with 4.44 microM BA at 100 ml flask capacity. This was further subcultured at increasing flask capacity (150, 250, and 500 ml) for shoot proliferation. Of the different concentrations of BA and flask capacities tested, 4.44 microM BA and 500 ml flask capacity were found to produce a maximum of 85.5 shoots after 30 d of culture. Shoot proliferation was found to increase with increasing flask capacity whereas shoot number decreased with increasing BA concentration (>4.44 microM). Individual shoots were isolated and rooted on MS medium containing 8.56 microM indole-3-acetic acid (IAA). Then the plantlets were acclimatized under standard laboratory conditions and later under greenhouse conditions. Fresh leaves were collected from greenhouse-grown plants and subjected to essential oil analysis by the simultaneous distillation and extraction method. GC-MS results revealed the presence of 88 components and the extracted oil was rich in camphor (16.8%), alpha-thujone (11.3%), germacrene D (7.2%), camphene (6.5%), 1,8-cineole (5.8%) and beta-caryophyllene (5.4%). This in vitro strategy can be a reliable method for the steady production of a large number of plants for essential oil production, which is reported for the first time for A. vulgaris. 相似文献
82.
Kumari S. Panigrahi A. Singh S. K. Mohapatra M. Khanna A. S. Mishra S. K. Pradhan S. K. 《Journal of Applied Electrochemistry》2019,49(12):1157-1166
Journal of Applied Electrochemistry - The present work is focused on the effects of graphene addition on the electrochemical performance of environmentally benign nanostructured... 相似文献
83.
Effects of baking conditions on colour,texture and crumb grain characteristics of Chhana Podo
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Anu Kumari Franklin Magdaline Eljeeva Emerald Vikram Simha Heartwin A Pushpadass 《International Journal of Dairy Technology》2015,68(2):270-280
Baking, the key step in the preparation of Chhana Podo, involves simultaneous heat and mass transfer that induces physicochemical and structural changes in the product. The effects of baking conditions on colour, texture and crumb grain development in the product were evaluated. The browning index of baked Podo increased from the initial value of 15.7 to 95, 101 and 112, at baking temperatures of 120, 135 and 150 °C, respectively. Browning kinetics followed the logistic model (R2 > 0.98) with an activation energy of 17.81 kJ/mol. In general, crumb grain characteristics such as mean cell area, cell density and cell‐to‐total area ratio increased with increase in baking time and temperature. Textural attributes such as hardness, chewiness and gumminess increased with baking time and temperature while springiness, cohesiveness and resilience increased up to 40 min due to the filling‐up of pores water and liquid by fat and expanding water, but decreased thereafter. 相似文献
84.
Multimedia Tools and Applications - The identification of MR images of the brain with tumours is one of the most critical tasks of any brain tumour (BT) detection system. Interestingly, because of... 相似文献
85.
Multimedia Tools and Applications - Today’s digital era has undertaken most of the responsibilities of public and private sectors, not only the industries or big organizations dependent on... 相似文献
86.
Selva Nidhyanandhan S. Sindhuja R. Selva Kumari R. Shantha 《Wireless Personal Communications》2020,114(4):2909-2921
Wireless Personal Communications - Major issue in marine environment imaging is the expulsion of hazy scenes caused by natural phenomena such as absorption and scattering in underwater images. The... 相似文献
87.
88.
The mobility and openness of wireless communication technologies make Mobile Healthcare Systems (mHealth) potentially exposed to a number of potential attacks, which significantly undermines their utility and impedes their widespread deployment. Attackers and criminals, even without knowing the context of the transmitted data, with simple eavesdropping on the wireless links, may benefit a lot from linking activities to the identities of patient’s sensors and medical staff members. These vulnerabilities apply to all tiers of the mHealth system. A new anonymous mutual authentication scheme for three-tier mobile healthcare systems with wearable sensors is proposed in this paper. Our scheme consists of three protocols: Protocol-1 allows the anonymous authentication nodes (mobile users and controller nodes) and the HSP medical server in the third tier, while Protocol-2 realizes the anonymous authentication between mobile users and controller nodes in the second tier, and Protocol-3 achieves the anonymous authentication between controller nodes and the wearable body sensors in the first tier. In the design of our protocols, the variation in the resource constraints of the different nodes in the mHealth system are taken into consideration so that our protocols make a better trade-off among security, efficiency and practicality. The security of our protocols are analyzed through rigorous formal proofs using BAN logic tool and informal discussions of security features, possible attacks and countermeasures. Besides, the efficiency of our protocols are concretely evaluated and compared with related schemes. The comparisons show that our scheme outperforms the previous schemes and provides more complete and integrated anonymous authentication services. Finally, the security of our protocols are evaluated by using the Automated Validation of Internet Security Protocols and Applications and the SPAN animator software. The simulation results show that our scheme is secure and satisfy all the specified privacy and authentication goals. 相似文献
89.
Wireless Networks - Since the advent of 1G through 5G networks, telecommunication industry has gone through phenomenal transformation in the way we communicate, we work, and we socialize. In dense... 相似文献
90.
Diatoms are single‐celled microalgae that produce a large variety of hierarchically porous, silica‐based microparticles as cell wall material. The presence of genetically encoded silica nanopatterns endows the biosilica with favorable properties for a wide range of applications including catalysis, chemical sensing, photonics, and drug delivery. Enhancing the performance of diatom biosilica requires i) a better understanding of the structure–property relationship in this material, and ii) methods that enable the manipulation of the biosilica structure and properties in a targeted manner. Here, genetic engineering of the diatom Thalassiosira pseudonana is employed to immobilize enzymes (glucose oxidase and horseradish peroxidase) into structurally distinct regions of the biosilica, which are termed valves and girdle bands. Remarkably, glucose oxidase in girdle bands exhibits >3‐fold higher catalytic activities compared to its location in valves. It is demonstrated through enzyme accessibility studies, protein engineering, and genetic engineering of biosilica morphology that the divergent enzyme activities are caused by the differences in the inherent silica nanopatterns of valves and girdle bands. This work highlights the importance of silica nanoscale architecture for the activity of immobilized enzymes and provides unprecedented tools for the biotechnological production of silica microparticles with tailored catalytic activities and anisotropic functionalities. 相似文献