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301.
The dynamics of protons in a one-dimensional hydrogen-bonded (HB) polypeptide chain (PC) is investigated theoretically. A new Hamiltonian is formulated with the inclusion of higher-order molecular interactions between peptide groups (PGs). The wave function of the excitation state of a single particle is replaced by a new wave function of a two-quanta quasi-coherent state. The dynamics is governed by a higher-order nonlinear Schrödinger equation and the energy transport is performed by the proton soliton. A nonlinear multiple-scale perturbation analysis has been performed and the evolution of soliton parameters such as velocity and amplitude is explored numerically. The proton soliton is thermally stable and very robust against these perturbations. The energy transport by the proton soliton is more appropriate to understand the mechanism of energy transfer in biological processes such as muscle contraction, DNA replication, and neuro-electric pulse transfer on biomembranes. 相似文献
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M. Jayanthi N. Murali Mohan P. K. Mandal 《Journal of plant biochemistry and biotechnology.》2011,20(2):249-251
Direct embryogenesis without an intervening callus phase from cotyledonary nodes of germinated immature zygotic embryos of hybrids viz. DG1 and DG21 of oil palm (Elaeis guineensis) is reported here. Direct embryogenesis was achieved when the cotyledonary nodes of germinated immature zygotic embryos were cultured in dark for 8 weeks on Eeuwens media (Y3) supplemented with 40 μM 2,4-Dichlorophenoxyacetic acid (2,4-D), 40 μM α-Naphthaleneacetic acid (NAA), 10 μM 2,4,5-Trichorophenoxyacetic acid (2,4,5-T), 10 μM Thiadiazuron (TDZ), 10 μM 6-Benzyladenine (BA). The globular embryos with clear suspensor region appeared directly on the explants and multiplied. On subculture to fresh media, the other stages such as torpedo and heart shaped embryos were seen. On transfer to light in Y3 media containing BA (2 μM) and ABA (1 μM) they matured into complete plantlets. In 2% of the cultures secondary embryogenesis also was seen. Along with several other advantages of direct somatic embryogenesis this protocol opens up the prospect of genetic transformation in this important commercial crop. 相似文献
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RESPONSE OF IPS GRANDICOLLIS (EICHHOFF) ADULTS (COLEOPTERA;SCOLYTIDAE) TO SITES IN BARK INITIATED BY OTHERS OF THE SAME SPECIES 总被引:1,自引:1,他引:0
Jayanthi P. Witanachchi 《Australian Journal of Entomology》1986,25(1):41-46
b
Dispersing males and females of Ips grandicollis , whether mated or virgin, initiated galleries on experimental logs held in a naturally infested P. radiata plantation. A few females initiated galleries despite the presence of adjacent male-initiated galleries. Males responded to logs bearing females by entering 41% of the female-initiated galleries. The pattern of entry of these males differed depending on whether the entrance to the female-initiated gallery was blocked by frass or not. The findings of this study has led to interesting speculations about the behaviour and biology of this species. 相似文献
Dispersing males and females of Ips grandicollis , whether mated or virgin, initiated galleries on experimental logs held in a naturally infested P. radiata plantation. A few females initiated galleries despite the presence of adjacent male-initiated galleries. Males responded to logs bearing females by entering 41% of the female-initiated galleries. The pattern of entry of these males differed depending on whether the entrance to the female-initiated gallery was blocked by frass or not. The findings of this study has led to interesting speculations about the behaviour and biology of this species. 相似文献
306.
Aachal A. Sharma M. Rakshita Payal P. Pradhan K. A. K. Durga Prasad Siju Mishra K. Jayanthi D. Haranath 《Luminescence》2023,38(9):1668-1677
Psoriasis is a noncontagious, long-lasting skin infection that affects many people around the world. Numerous therapeutic artificial treatments are available for the treatment of psoriasis, such as photodynamic therapy using broadband ultraviolet (UV) lamps, which have harmful effects on human skin. Similarly, the natural healing systems such as sunlight have a higher risk of sunburn and can cause dangerous forms of skin cancer. Significant light emission of a specific wavelength (in the UV range), and phosphor-based devices demonstrate the effectiveness of treating psoriasis without damaging the skin. Gd3+-doped calcium magnesium silicate [Ca2MgSi2O7:Gd3+,(CMS:Gd3+)] phosphor is one of the ideal phosphors that emit specific narrow UV wavelengths for curing psoriasis and is in great demand in the field of dermatology. Photoluminescence analysis at room temperature (~25°C) shows that the synthesized CMS:Gd3+ phosphor emits narrowband UV-B light with a peak intensity at 314 nm. Comparative studies of the standard action spectrum of psoriasis with the emission spectrum of the CMS:Gd3+ phosphor show that the synthesized phosphor was the most suitable material for treating a variety of diseases, including psoriasis, vitiligo, type-1 diabetes, dental disease, sleep and mood disorders, and other skin diseases. 相似文献
307.
The function of DL alpha-lipoic acid (6,8-thioctic acid) as a prosthetic group in the oxidative decarboxylation of alpha-keto acids, pyruvate and alpha-ketoglutarate in mitochondria is well known. Its role is well extended to certain reactions in lipid biosynthesis. In addition, lipoic acid has been shown to prevent the induced precipitation of calcium oxalate crystals in the renal tissues of laboratory animals. Here, the effect of alpha-lipoic acid was studied, on altered tissue lipid levels manifested during experimental renal lithiasis. Raised tissue cholesterol, triglyceride and low phospholipid levels were some of the striking significant observations made in calculogenic rats. Lipoic acid treatment reduced tissue cholesterol and triglyceride levels significantly and raised phospholipids. The alterations may have a bearing in relation to calcium oxalate stone formation. 相似文献