Kerala Libraries Network (KELNET): a Proposal

Visualizes the conceptual framework and propose the development of a Kerala Library Network (KELNET) by exploring and exploiting the available and the existing social infrastructures, social softwares, open standards and technologies

Implications of organic management on yield, tuber quality and soil health in yams in the humid tropics

Global consciousness of food safety, health and environmental issues has stimulated interest in alternative agricultural systems like organic farming. Since information on organic farming of tuber crops is meagre, a field experiment was conducted in split plot design over a five-year period at Central Tuber Crops Research Institute, India. The aims were to evaluate the impact of organic, conventional and traditional production systems on yield, proximate composition and mineral content of tubers and soil physico-chemical and biological properties in three species of Dioscorea (white yam: D. rotundata, greater yam: D. alata and lesser yam: D. esculenta). The production systems were assigned to main plots and species to subplots. Organic farming (20.34 t ha-1) produced significantly higher yield over conventional practice (18.64 t ha-1) by 9%. All the species responded well to organic management, which lowered the bulk density and particle density slightly and improved the water holding capacity (by 15%) of soil. Tuber quality was improved with significantly higher Ca (72.67 mg 100g-1), slightly higher dry matter, crude protein, K and Mg contents. Organic plots showed significantly higher available K, by 34% and pH, by 0.46 unit and higher soil organic matter by 14%. The dehydrogenase enzyme activity (1.174 μg TPF formed g-1 soil h-1), population of bacteria, fungi and P solubilizers were promoted by 14%, 23%, 17% and 22% respectively. Thus organic farming was found to be an eco-friendly management strategy in yams for sustainable yield of quality tubers besides maintaining soil health. Technology involving farmyard manure, green manuring, neem cake, biofertilizers and ash was standardized

Enhanced biomass production study on probiotic Bacillus subtilis SK09 by medium optimization using response surface methodology

The culture conditions of lactose fermenting, spore forming probiotic Bacillus subtilis SK09 isolated from dairy effluent were optimized by response surface methodology to maximize the biomass production. The student’s t-test of the Placket-Burman screening design revealed that the effects of pH, ammonium citrate and peptone were more significant and these variables were further optimized using central composite design. The various effects of the variables were studied using Fisher’s F-test for analysis of variance and a second order polynomial model was developed which fitted well with high statistical reliability and significance. The optimal value of significant variables was found to be pH (6.72), ammonium citrate (0.164%) and peptone (0.85%). At these optimized conditions, the maximum biomass yield was estimated to be 10.051*109 CFU/ml. By employing this statistical design, enhanced yield of probiotic biomass B. subtilis SK09 was achieved using cost-effective medium.Key words: Probiotics, response surface methodology, central composite design, Bacillus subtilis SK09, lactose intolerance disorder

Stabilized Lateritic Blocks Reinforced With Fibrous Coir Wastes

Tropical countries are rich in lateritic soil, a naturally available raw material for building construction. But its potential in block making is not yet satisfactorily explored. This paper focuses on an experimental investigation for improvising stabilized lateritic blocks (SLB) with coir cutting wastes from coir industry as reinforcing elements. Lateritic soil used in this study showed a higher percentage of clay content. Hence it was pre-stabilized with sand and cement. Blocks were prepared by stabilizing it further with waste fibrous additives and tested for strength and durability. Considerable improvement in strength (compressive strength @19% and tensile strength @ 9%) and durability characteristics were exhibited by the new fiber reinforced lateritic blocks (FRLB) with fiber content of 0.5%. These blocks can be successfully proposed for load bearing construction and as well as for earthquake resistant structure

On The Center Sets and Center Numbers of Some Graph Classes

For a set $S$ of vertices and the vertex $v$ in a connected graph $G$, $\displaystyle\max_{x \in S}d(x,v)$ is called the $S$-eccentricity of $v$ in $G$. The set of vertices with minimum $S$-eccentricity is called the $S$-center of $G$. Any set $A$ of vertices of $G$ such that $A$ is an $S$-center for some set $S$ of vertices of $G$ is called a center set. We identify the center sets of certain classes of graphs namely, Block graphs, $K_{m,n}$, $K_n-e$, wheel graphs, odd cycles and symmetric even graphs and enumerate them for many of these graph classes. We also introduce the concept of center number which is defined as the number of distinct center sets of a graph and determine the center number of some graph classes

Kerala Libraries Network (KELNET): a Proposal

Visualizes the conceptual framework and propose the development of a Kerala Library Network (KELNET) by exploring and exploiting the available and the existing social infrastructures, social softwares, open standards and technologies

Constraints on the Physical Parameters of TeV Blazars

We consider the constraints on the physical parameters of a homogeneous SSC model that can be derived from the spectral shape and variability of TeV blazars. Assuming that the relativistic electron spectrum is a broken power law, where the break energy $\gamma_b$ is a free parameter, we write the analytical formulae that allow to connect the physical parameters of the model to observable quantities. The constraints can be summarized in a plane where the coordinates are the Doppler factor and the magnetic field. The consistency between the break energy and the balance between cooling and escape and the interpretation of the soft photon lags measured in some sources as radiative cooling times are treated as additional independent constraints. We apply themethod to the case of three well known blazars, PKS 2155-304, Mrk 421 and Mrk 501.Comment: 36 pages, incl. 6 figures in PS format, AAS LaTeX, to be published in ApJ, Dec 199

IS ORGANIC TUBER PRODUCTION PROMISING? FOCUS ON IMPLICATIONS, TECHNOLOGIES AND LEARNING SYSTEM DEVELOPMENT

Alternative soil management practices like organic farming assume special significance in the context of global warming and climate change for sustainable and safe food production. Organic farming enables a clean environment by promoting soil quality and sequestering soil organic carbon. Cassava, yams (white yam, greater yam and lesser yam) and edible aroids (elephant foot yam, taro and tannia) are tuberous vegetables with good taste and nutritive value. Seven field experiments were conducted in series at the Central Tuber Crops Research Institute, Thiruvananthapuram, India, over a decade (2004-2013) to compare the varietal response, yield, quality and soil properties under organic farming over conventional system in these crops and to develop a learning system based on the data generated. The industrial as well as domestic varieties of cassava, the elite and local varieties of elephant foot yam and taro and the three species of Dioscorea (yams) were on a par under both systems. However, the industrial variety of cassava yielded more under organic farming than conventional practice. The yield trend over the years as well as pooled analysis indicated the significantly superior performance of organic farming in elephant foot yam. Organic farming produced slightly higher yield in cassava and trailing genotypes of yams. This indicates that elephant foot yam was the most responsive to organic management followed by yams and cassava. Taro and dwarf white yam preferred chemical farming as slight yield reduction (2-5%) was noticed under organic farming with almost similar tuber quality. Thus organic management promoted yield by 8%, 20%, 9%, 11% and 7% over conventional practice in cassava, elephant foot yam, white yam, greater yam and lesser yam respectively. The tuber quality was improved with higher dry matter, starch, crude protein, K, Ca and Mg contents. The anti-nutritional factors, oxalate content in elephant foot yam and cyanogenic glucoside content in cassava were lowered by 21 and 12.4% respectively. Organic plots had significantly higher water holding capacity, pH, available K, Fe, Mn and Cu, higher soil organic matter, available N, P, exchangeable Ca and Mg, dehydrogenase enzyme activity and microbial count. Cost-benefit analysis in elephant foot yam indicated that the net profit was 28% higher and additional income of Rs. 47,716 ha-1 was obtained due to organic farming. The on station technology developed for elephant foot yam was validated and popularized through on farm trials in 10 sites (5 ha) under National Horticulture Mission funded programme. The technology is included in the Package of Practices Recommendations for crops of Kerala Agricultural University. A learning system was developed using artificial neural networks (ANN) to predict the performance of elephant foot yam organic production system. Use of organically produced seed materials, seed treatment in cow-dung, neem cake, bio-inoculant slurry, farmyard manure incubated with bio-inoculants, green manuring, use of neem cake, bio-fertilizers and ash formed the strategies for organic production. Organic farming is an eco-friendly management strategy that enables 10-20% higher yield, quality tubers and maintenance of soil health in tuber crops

Organic Production of Tuberous Vegetables: Agronomic, Nutritional and Economic Benefits

Global awareness of health and environmental issues has stimulated interest in alternative Agricultural systems like organic farming. Elephant foot yam (Amorphophallus paeoniifolius) and yams (Dioscorea spp.) are ethnic starchy vegetables with high energy, nutritive and medicinal values. Field experiments were conducted at the Central Tuber Crops Research Institute, Thiruvananthapuram, India, during 2004-2011 to assess the agronomic, nutritional and economic advantages of organic farming over conventional system in these crops. Organic farming resulted in 10-20% higher yield over conventional practice in these crops. A net profit of Rs 2,15,776 ha-1, which was 28% higher over chemical based farming was obtained under organic management in elephant foot yam. Elite and local varieties responded equally well to organic and conventional farming in elephant foot yam. White yam, greater yam and lesser yam responded similarly to both the systems, with slightly higher yield under organic practice. Soil physico-chemical properties and microbial count were also improved under organic management. Organic farming scored significantly higher soil quality index (1.93) than conventional practice (1.46). The soil quality index was driven by water holding capacity, pH and available Zn followed by soil organic matter. Tuber quality was improved with higher dry matter, starch, crude protein and lower oxalate contents. Cost effective technologies were field validated