Strange Nonchaotic Attractors

Aperiodic dynamics which is nonchaotic is realized on Strange Nonchaotic attractors (SNAs). Such attractors are generic in quasiperiodically driven nonlinear systems, and like strange attractors, are geometrically fractal. The largest Lyapunov exponent is zero or negative: trajectories do not show exponential sensitivity to initial conditions. In recent years, SNAs have been seen in a number of diverse experimental situations ranging from quasiperiodically driven mechanical or electronic systems to plasma discharges. An important connection is the equivalence between a quasiperiodically driven system and the Schr\"odinger equation for a particle in a related quasiperiodic potential, giving a correspondence between the localized states of the quantum problem with SNAs in the related dynamical system. In this review we discuss the main conceptual issues in the study of SNAs, including the different bifurcations or routes for the creation of such attractors, the methods of characterization, and the nature of dynamical transitions in quasiperiodically forced systems. The variation of the Lyapunov exponent, and the qualitative and quantitative aspects of its local fluctuation properties, has emerged as an important means of studying fractal attractors, and this analysis finds useful application here. The ubiquity of such attractors, in conjunction with their several unusual properties, suggest novel applications.Comment: 34 pages, 9 figures(5 figures are in ps format and four figures are in gif format

Bifurcations and transitions in the quasiperiodically driven logistic map

We discuss several bifurcation phenomena that occur in the quasiperiodically driven logistic map. This system can have strange nonchaotic attractors (SNAs) in addition to chaotic and regular attractors; on SNAs the dynamics is aperiodic, but the largest Lyapunov exponent is nonpositive. There are a number of different transitions that occur here, from periodic attractors to SNAs, from SNAs to chaotic attractors, etc. We describe some of these transitions by examining the behavior of the largest Lyapunov exponent, distributions of finite time Lyapunov exponents and the invariant densities in the phase space.Comment: 17 Pages, 8 Figures(four figures are in ps format and four figures are in gif forma

Long-term results of patients with type 2 diabetes attending a multidisciplinary diabetes kidney disease clinic

Background: Diabetic and chronic kidney disease together tend to worsen the outcomes. A newer approach to treat both the comorbid disease can slow down the prognosis of both the disease leading to quality of life. Aim: To evaluate the outcomes when the patients are treated simultaneously for chronic kidney disease and diabetes at a diabetic kidney disease clinic MethodS: The study was conducted amongst two group of patient. The first group had diabetes and chronic kidney diseases. Doctors treating the diabetes referred these patients to a diabetic kidney disease clinic. While the other group of patients were not treated at diabetic kidney disease center but they had comparable diabetes and chronic kidney disease. The prognosis was tracked in both the groups; the kidney of the patients was monitored if it had reach stage 5 kidney disease and the glomerular filtration rate was less than 1.5 milliliter per minute and per 1.73 m2. Result: During the follow up the reports of the patients were analyzed it was observed that the 49.4% patients had reached chronic kidney disease stage 5 who were treated at the diabetic kidney disease clinic. 55.5% of the patients of the patients not treated at diabetic kidney disease clinic reached the chronic kidney disease stage 5. When the difference was compared statistically it was found to be statistically significant. Conclusion: From this study it is concluded that when patients are treated for chronic kidney disease and diabetes simultaneously the prognosis towards the end stage kidney is delayed. When multidisciplinary clinics focus on the management of diabetes and kidney disease it can add years of quality life for the patients. Recommendation: Renin–angiotensin–aldosterone system inhibitors are strongly recommended for patients with diabetes, hypertension, and albuminuria

Absorption spectrometric macronutrients review of soil health during taro crop production

The purpose of this study was absorption spectrometric assessment the soil health of the soil from the taro growing areas of Taveuni, Fiji. The soil samples were collected in four cycles during taro cultivation period. The soil samples were analyzed for macronutrients (Ca, Mg, K, P and NO3–-N), soil organic matter (SOM) and soil pH. In general, the soil pH at all sites showed lower than the ideal pH (5.6–6.6) for taro planting throughout the cropping cycle. The results showed the significant loss in SOM from taro planting (15.41%) till harvesting (5.63%). Pronounced decrease in levels NO3–_N (18.29 to 13.86 mg kg−1), P (45.97 to 25.71 mg kg−1), K (77.90 to 22.96 mg kg−1), Ca (62.20 to 27.59 mg kg−1) and Mg (316.10 to 121.48 mg kg−1) were recorded from planting till harvesting for different sites. There was significant reduction in the soil macronutrients and SOM in all the four study sites and some sites showed below critical level and critical to medium levels of these nutrients in the soil at the end of the harvesting period of taro. The statistical analysis of the soil test data confirmed the declining trend of the soil health on the island of Taveuni, Fiji

Degummed Pongamia oil – Ethanol microemulsions as novel alternative CI engine fuels for remote Small Island Developing States: preparation, characterization, engine performance and emissions characteristics

Diminishing fossil fuel reserves, rising market price for diesel and the need to combat greenhouse gas emissions have led to the development of a crucial area of research into alternative fuels for diesel engines. In this work, a hybrid fuel was prepared for the first time by blending Pongamia oil, hydrated ethanol (95% purity) and butanol (as a surfactant). To eliminate engine modification and reduce injector clogging in the diesel engine, degummed Pongamia oil was utilized for preparing hybrid fuels. The results show that the density and viscosity of Pongamia oil reduced considerably after blending with ethanol and was brought closer to that of diesel. The gross calorific values were comparable with that of diesel. The brake thermal efficiencies of using hybrid fuels on a compression ignition engine were very similar to that of diesel. The emissions characteristics of hybrid fuels show reduced emissions of CO2, NOx and SO2. The hybrid fuel blends E22B27DPO51 and E17B16DPO67 prepared with degummed Pongamia oil show the lowest emissions. Thus, these hybrid fuels have the potential to substitute diesel to run diesel powered inter-island shipping vessels, fishing boats and smaller power plants for household electricity in remote and outer islands of developing countries

Synthesis, Spectroscopic and Physicochemical Characterization and Biological Activity of Co(II) and Ni(II) Coordination Compounds with 4-Aminoantipyrine Thiosemicarbazone

We describe the synthesis and characterization of cobalt(II) and nickel(II) coordination compounds of 4[N-(furan-2’-aldimine)amino]antipyrine thiosemicarbazone (FFAAPTS) and 4[N-(4'-nitrobenzalidene) amino]antipyrine thiosemicarbazone (4'-NO2BAAPTS). All the isolated compounds have the general composition MX2(L)(H2O) (M = Co2+ or Ni2+; X = Cl, Br, NO3, NCS or CH3COO; L = FFAAPTS or 4'-NO2BAAPTS) and M(ClO4)2(L)2 (M = Co2+ or Ni2+; L = FFAAPTS or 4'-NO2BAAPTS). Infrared spectral studies indicate that both the thiosemicarbazones coordinate in their neutral form and they act as {N,N,S} tridentate chelating ligands. Room temperature magnetic measurements and electronic spectral studies suggest the distorted octahedral geometries of the prepared complexes. Thermogravimetric studies are also reported and the possible structures of the complexes are proposed. Antibacterial and antifungal properties of these metal-coordination compounds have also been studied

Research Notes: Soybean breeding research in India

Soybean (Glycine max (L.) Merrill) is the miracle crop of the twentieth century. It is a new introduction to Indian agriculture. In view of chronic shortage of protein and oil in this country, soybean should be welcome introduction to provide the much needed stability and boost to the production of these two essential items of food (Saxena, 1975)

First assessment of metals contamination in road dust and roadside soil of Suva City, Fiji

Studies have claimed that road dust and roadside soil are potential banks of pollutants generally in urban areas. Thus, quantifying the concentrations of metals in an urban area is a prerequisite for assessing pollution and their health effects. Hence, this study reports the concentration of the metals, such as Cd, Co, Cr, Ni, Cu, Pb, Zn, and Fe, in the road dust and the roadside soil of Suva City. A total number of 45 road dust and 36 roadside soil samples were collected at 18 different locations around Suva City with potential traffic influence and analysed. The respective metals concentration in the road dust and roadside soil samples of Suva City were Cd (3.7 and 3.1 mg/kg), Co (35.0 and 33.2 mg/kg), Cr (40.0 and 34.0 mg/kg), Ni (54.3 and 32.4 mg/kg), Cu (172.3 and 265.7 mg/kg), Pb (71.0 and 59.3 mg/kg), Zn (685.0 and 507.0 mg/kg), and Fe (41,010.4 and 39,525.5 mg/kg) and showed the decreasing order as Fe > Zn > Cu > Pb > Ni > Cr > Co > Cd and Fe > Zn > Cu > Pb > Cr > Co > Ni > Cd for road dust and roadside soil, respectively. Furthermore, the mean values of the metals surpassed their background levels, except for Fe, whereas the mean values of Cd, Ni, Cu, and Zn have exceeded their permissible limits in road dust. Similarly, Cd, Cu, and Zn have exceeded their permissible limit in roadside soil except for Ni. The geo-accumulation index (Igeo) assessment of Suva City road dust thus indicated nonpolluted to moderate pollution by Ni and Cu and moderate pollution by Zn. The Igeo assessment of the roadside soil showed moderately polluted by Cu and Zn but no pollution from the remaining studied metals. Overall, the study indicated that the sampling locations at an industrial site of Suva City is highly predominated with almost all of the studied metals and is a concern to the general public who live and work within the vicinity of Walu Bay industrial area