Dynamical complexities in a tri-trophic hybrid food chain model with Holling type II and Crowley–Martin functional responses

We study how predator behavior influences community dynamics of predatorprey systems. It turns out that predator behavior plays a dominant role in community dynamics. The hybrid model studied in this paper reveals that period-doubling and period-doubling reversals can generate short-term recurrent chaos (STRC), which mimics chaotic dynamics observed in natural populations. STRC manifests itself when deterministic changes in a system parameter interrupt chaotic behavior at unpredictable intervals. Numerical results reinforce an earlier suggestion that period-doubling reversals could control chaotic dynamics in ecological models. In ecological terms, the prey and intermediate predator populations may go to extinction in the event of a catastrophe. The top predator is always a survivor. In contrast to this, this is not the case when the constituent populations are interacting through Holling type II functional response. Even this top predator can go to extinction in the event of such catastrophes

Cellular Automata with Synthetic Image A Secure Image Communication with Transform Domain

    Image encryption has attained a great attention due to the necessity to safeguard confidential images. Digital documents, site images, battlefield photographs, etc. need a secure approach for sharing in an open channel. Hardware – software co-design is a better option for exploiting unique features to cipher the confidential images. Cellular automata (CA) and synthetic image influenced transform domain approach for image encryption is proposed in this paper. The digital image is initially divided into four subsections by applying integer wavelet transform. Confusion is accomplished on low – low section of the transformed image using CA rules 90 and 150. The first level of diffusion with consecutive XORing operation of image pixels is initiated by CA rule 42. A synthetic random key image is developed by extracting true random bits generated by Cyclone V field programmable gate array 5CSEMA5F31C6. This random image plays an important role in second level of diffusion. The proposed confusion and two level diffusion assisted image encryption approach has been validated through the entropy, correlation, histogram, number of pixels change rate, unified average change intensity, contrast and encryption quality analyses

FORMULATION AND EVALUATAION OF COLON TARGETED MATRIX TABLET OF NAPROXEN

Objectives: The objective of the present study is to formulate the Colon targeted delivery containing Naproxen for chronopharmaceutical drug delivery system (ChrDDS) for treatment of rheumatoid arthritis, which are influenced by circadian rhythm. Chronopharmaceutical drug delivery system is capable of delivering drug when and where drug required most. Naproxen would remain in the GIT Fluid, intestinal fluid and it will liberate only in colonic fluid and gives better absorption. Methods: The matrix core tablets of Naproxen were prepared by direct compression method by using Crosspovidone as superdisintegrant. From those optimesd batch core tablet is further going for coating. Coating was carried out by using natural gums like Xanthan gum, Guar gum, Chitosan and Pectin alone and in combination. Results: From the experimental work Crosspovidone shows good drug release. Coating done by combination of Xanthan Gum and Chitosan shows better drug release (98.24%) in sustained release manner than other natural gums like Guar gum and pectin. Conclusion: From the results obtained, it was concluded that the programmable Chronopharmaceutical drug release has been achieved from Crosspovidone containing core tablet compressed coated by combination of Xanthan gum and Chitosan over a 10 hrs period, consistent with the demands of chronotherapeutic drug delivery for rheumatoid arthritis

Spin-accumulation and Andreev-reflection in a mesoscopic ferromagnetic wire

The electron transport though ferromagnetic metal-superconducting hybrid devices is considered in the non-equilibrium Green's function formalism in the quasiclassical approximation. Attention if focused on the limit in which the exchange splitting in the ferromagnet is much larger than the superconducting energy gap. Transport properties are then governed by an interplay between spin-accumulation close to the interface and Andreev reflection at the interface. We find that the resistance can either be enhanced or lowered in comparison to the normal case and can have a non-monotonic temperature and voltage dependence. In the non-linear voltage regime electron heating effects may govern the transport properties, leading to qualitative different behaviour than in the absence of heating effects. Recent experimental results on the effect of the superconductor on the conductance of the ferromagnet can be understood by our results for the energy-dependent interface resistance together with effects of spin- accumulation without invoking long range pairing correlations in the ferromagnet.Comment: 15 pages, 12 figures included, submitted to PR

Evaluation of harvesting time and standardization of distillation duration for higher essential oil content and quality in German chamomile (Chamomilla recutita L.)

Essential oil yield and composition in aromatic crops might be affected by genetic, agronomical and environmental factors but till date there is no clear information about the harvesting time and distillation for higher essential oil content without affecting quality. The current study was carried out to evaluate harvesting of chamomile flowers without herb and with herb part at three different times (6 A.M., 12 P.M. and 6 P.M.) and four distillation treatments (3 h, 4 h, 5 h & 6 h) for dried chamomile flowers. Results indicated that essential oil content was more in chamomile flowers without herb (0.15-0.18%) as compared to flowers with herb (0.06-0.09%). Essential oil content in chamomile flowers without herb was found statistically at par at harvest time of 12 P.M. (0.18%) and 6 P.M. (0.18%) and significantly higher than harvesting time of 6 A.M. (0.15%). Essential oil of chamomile flowers without herb contained maximum α-bisabolol oxide-B, (Z)-spiroether, and chamazulene at 12 P.M. and 6 P.M. while, α-bisabolone oxide-A and α-bisabolol oxide-A were maximum at 6 A.M. and (E)-β-farnesene was more at 12 P.M. Similarly, in distillation experiment, higher oil content was observed in chamomile dried flowers which were hydro-distilled for 6 h (1.20%) compared to other hydro-distillation durations. Marker compounds i.e. α-bisabolol oxide-A, α-bisabolone oxide-A, α-bisabolol oxide-B, (E)-β-farnesene and chamazulene were more at 5 h and 6 h distillation duration while (Z)-spiroether was more at 3 h distillation duration. The present study showed that in order to obtain higher essential oil, flowers without herb harvested at 12 P.M or 6 P.M. should be subjected to 5-6 h hydro-distillation

Impact of biotic and abiotic factors on lac production and peoples’ livelihood improvement in India-An overview

In India, Madhya Pradesh is the third largest lac producing state after Chhattisgarh and Jharkhand, as they contribute 12, 16 and 60%, respectively in total country’s lac production. Lac is produced in ten out of eleven agro-climatic zones of Madhya Pradesh. In total lac production of the state, Baisakhi (Butea monosperma, inoculated in October-November) crop contributes 76% followed by 19% by Katki (Butea monosperma, inoculated in June-July), 3% by Aghani (Schleichera oleosa, inoculated in June-July) and 2% by Jethwi (Schleichera oleosa, inoculated in January-February). Ranchi was leading lac producing district followed by Simdega, Gumla, Khunti of Jharkhand and Seoni district of Madhya Pradesh. Increasing summer temperature up to 45 ?C, the country’s lac production was declined from 20,050 tons in 2003-04 to 16978 tons in 2014-15. In case of biotic factors, Tachardiaephagus tachardiae and Tetrastichus purpureus are the most abundant lac associated parasites and Eublemma amabilis and Pseudohypatopa pulverea are the most destructive key predators of lac insects. By combating these hindrances, lac cultivation generated an employment for 16-160 man days. Lac cultivation produces maximum gross return (Rs. 9,77,600) from 100 Kusum host plants, and the highest Benefit-Cost (6.80) ratio was recorded for Ber-kusumi (Ziziphus mauritiana- Schleichera oleosa) crop in Ranchi, Jharkhand. In this context, the study finds out obstacles in lac production of India and suggests some control measures to improve lac producing peoples’ livelihood. &nbsp

Resonant transmission of normal electrons through Andreev states in ferromagnets

Giant oscillations of the conductance of a superconductor - ferromagnet - superconductor Andreev interferometer are predicted. The effect is due to the resonant transmission of normal electrons through Andreev levels when the voltage $V$ applied to the ferromagnet is close to $2h_0/e$ ($h_0$ is the spin-dependant part of the electron energy). The effect of bias voltage and phase difference between the superconductors on the current and the differential conductance is presented. These efects allow a direct spectroscopy of Andreev levels in the ferromagnet.Comment: 4 pages, 4 figure

RFLP mapping in Indian Mustard (Brassica juncea)

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Dislocation Kinks in Copper: Widths, Barriers, Effective Masses, and Quantum Tunneling

We calculate the widths, migration barriers, effective masses, and quantum tunneling rates of kinks and jogs in extended screw dislocations in copper, using an effective medium theory interatomic potential. The energy barriers and effective masses for moving a unit jog one lattice constant are close to typical atomic energies and masses: tunneling will be rare. The energy barriers and effective masses for the motion of kinks are unexpectedly small due to the spreading of the kinks over a large number of atoms. The effective masses of the kinks are so small that quantum fluctuations will be important. We discuss implications for quantum creep, kink--based tunneling centers, and Kondo resonances