Scattering of the double sine-Gordon kinks

We study the scattering of kink and antikink of the double sine-Gordon model. There is a critical value of the initial velocity $v_{cr}$ of the colliding kinks, which separates different regimes of the collision. At $v_{in}>v_{cr}$ we observe kinks reflection, while at $v_{in}<v_{cr}$ their interaction is complicated with capture and escape windows. We obtain the dependence of $v_{cr}$ on the parameter of the model. This dependence possesses a series of local maxima, which has not been reported by other authors. At some initial velocities below the critical value we observe a new phenomenon -- the escape of two oscillons in the final state. Besides that, at $v_{in}<v_{cr}$ we found the initial kinks' velocities at which the oscillons do not escape, and the final configuration looks like a bound state of two oscillons.Comment: 12 pages, 7 figures; v2: minor changes to match version published in EPJ

Multi-kink collisions in the ϕ6\phi^6 model

We study simultaneous collisions of two, three, and four kinks and antikinks of the $\phi^6$ model at the same spatial point. Unlike the $\phi^4$ kinks, the $\phi^6$ kinks are asymmetric and this enriches the variety of the collision scenarios. In our numerical simulations we observe both reflection and bound state formation depending on the number of kinks and on their spatial ordering in the initial configuration. We also analyze the extreme values of the energy densities and the field gradient observed during the collisions. Our results suggest that very high energy densities can be produced in multi-kink collisions in a controllable manner. Appearance of high energy density spots in multi-kink collisions can be important in various physical applications of the Klein-Gordon model.Comment: 21 pages, 8 figures; v2: minor changes to match version published in JHE

Nuevo protocolo de propagación invitro del tomate (Lycopersicon esculentum Mill.)

Introduction: A successful in vitro propagation system was developed for Sandra and Rocky cultivars of tomato plants (Lycopersicon esculentum Mill.) commonly grown in Kurdistan Region of Iraq by in vitro culture of shoot tips and node explants. Methods: Shoot tip and node explants were excised and cultured on basal MS medium containing several concentrations of BAP and Zeatin. Results: Multiple shoots formation of up to 2 shoots were obtained on MS medium supplemented with 2.0 mgl-1 Zeatin in node and shoot explants for the two cultivars. Microshoots were tested for root initiation on full MS medium supplemented with different concentrations of IBA, NAA and IAA. The best root formation was cultivar and 0.5 mgl-1 of NAA in rocky cultivar. Conclusion: The regenerated plants were successfully acclimatized and transplanted to the open field conditions

Discrete breathers assist energy transfer to ac driven nonlinear chains

One-dimensional chain of pointwise particles harmonically coupled with nearest neighbors and placed in six-order polynomial on-site potentials is considered. Power of the energy source in the form of single ac driven particles is calculated numerically for different amplitudes $A$ and frequencies $\omega$ within the linear phonon band. The results for the on-site potentials with hard and soft nonlinearity types are compared. For the hard-type nonlinearity, it is shown that when the driving frequency is close to (far from) the {\em upper} edge of the phonon band, the power of the energy source normalized to $A^2$ increases (decreases) with increasing $A$. In contrast, for the soft-type nonlinearity, the normalized power of the energy source increases (decreases) with increasing $A$ when the driving frequency is close to (far from) the {\em lower} edge of the phonon band. Our further demonstrations indicate that, in the case of hard (soft) anharmonicity, the chain can support movable discrete breathers (DBs) with frequencies above (below) the phonon band. It is the energy source quasi-periodically emitting moving DBs in the regime with driving frequency close to the DBs frequency, that induces the increase of the power. Therefore, our results here support the mechanism that the moving DBs can assist energy transfer from the ac driven particle to the chain.Comment: 11 pages, 13 figure

A Comprehensive Study on Pedestrians' Evacuation

Human beings face threats because of unexpected happenings, which can be avoided through an adequate crisis evacuation plan, which is vital to stop wound and demise as its negative results. Consequently, different typical evacuation pedestrians have been created. Moreover, through applied research, these models for various applications, reproductions, and conditions have been examined to present an operational model. Furthermore, new models have been developed to cooperate with system evacuation in residential places in case of unexpected events. This research has taken into account an inclusive and a 'systematic survey of pedestrian evacuation' to demonstrate models methods by focusing on the applications' features, techniques, implications, and after that gather them under various types, for example, classical models, hybridized models, and generic model. The current analysis assists scholars in this field of study to write their forthcoming papers about it, which can suggest a novel structure to recent typical intelligent reproduction with novel features

Use of Carica Papaya Enzymes for Enhancement of H2 Production and Degradation of Glucose, Protein, and Lipids

AbstractAnaerobic batch experimentswere carried out to examine the effect of supplementation of mixed culture bacteria with Carica papayaas enzymes for enhancement of hydrogen yield from degradation of glucose, protein, and lipids. The results showed that hydrogen yield (HY) based on protein and lipids degradation increased from 52.2 ± 7.5 to 130.6 ± 8.5ml/gprotein, and from 43.0 ± 5.3 to 64.8 ± 3.1ml/glipid respectively with addition of Carica papayaas enzymes source. This corresponded to substrate degradation efficiency of 51.3 ± 4.4% for protein and 33.7 ± 2.6% for lipids. However, the hydrogen yield and degradation efficiency of glucose was slightly improved by addition of Carica papayaas enzymes

Immobilization technology for enhancing bio-products industry

Immobilization is the limitation of movement of biocatalysts according to chemical or physical  treatment. Immobilized molecules technique using biomaterials and nano-biotechnology is a very  interesting topic that is touching almost all aspects of our life. Immobilized enzymes, molecules, and  cells have been used in a variety of scientific and industrial applications. Cell immobilization  biotechnology is a multidisciplinary area shown to have an important impact on many scientific  sub-disciplines, including biomedicine, pharmacology, cosmetology, food and agricultural sciences. Many  molecules have been immobilized and the majority of them are bio-molecules due to their biological and biomedical applications. Immobilization of enzymes has made them highly applicable to range of evolving biotechnologies. Immobilized enzymes have proven valuable for many medical applications including drug delivery systems, diagnosis and treatment of diseases, as well as in sensors for the  management of weight and diabetes. Enzyme immobilization is applied in textile industry. The  immobilized microorganism technology offers a multitude of advantages in wastewater treatment. The  immobilized cell systems were applied for the production of many organic compounds such as organic  acid and ethanol. The immobilization of tissue sections, cells and tissue components for histological and  immunohistochemical staining or detection systems is applicable nowadays. Cell immobilization could  potentially benefit food industry.Key words: Immobilized, bio-product, immobilization

Soliton-potential interaction in the nonlinear Klein-Gordon model

The interaction of solitons with external potentials in nonlinear Klein-Gordon field theory is investigated using an improved model. The presented model has been constructed with a better approximation for adding the potential to the Lagrangian through the metric of background space-time. The results of the model are compared with another model and the differences are discussed.Comment: 14 pages,8 figure