Microrheological Studies of Regenerated Silk Fibroin Solution by Video Microscopy

We have carried out studies on the rheological properties of regenerated silk fibroin (RSF) solution using video microscopy. The degummed silk from the Bombyx mori silkworm was used to prepare RSF solution by dissolving it in calcium nitrate tetrahydrate-methanol solvent. Measurements were carried out by tracking the position of an embedded micron-sized polystyrene bead within the RSF solution through video imaging. The time dependent mean squared displacement (MSD) of the bead in solution and hence, the complex shear modulus of this solution was calculated from the bead's position information. An optical tweezer was used to transport and locate the bead at any desired site within the micro-volume of the sample, to facilitate the subsequent free-bead video analysis. We present here the results of rheological measurements of the silk polymer network in solution over a frequency range, whose upper limit is the frame capture rate of our camera, at full resolution. By examining the distribution of MSD of beads at different locations within the sample volume, we demonstrate that this probe technique enables us to detect local inhomogeneties at micrometer length scales, not detectable either by a rheometer or from diffusing wave spectroscopy.Comment: 5 page

Multivariate analysis to evaluate geochemistry of groundwater in Varahi river basin of Udupi in Karnataka (India)

The Varahi Irrigation project dam site is located at approx. 6 km from Siddapura, Kundapura taluk, Udupi district with latitude of 13°39' 15" N and a longitude of 74°57'E. Groundwater quality in the study area was evaluated for its suitability for drinking and irrigation purposes by collecting 36 samples during pre-​monsoon period of the year 2005. The quality assessment was made by estg. physico-​chem. parameters, major cations and anions, besides irrigation quality parameters like SAR,​% Na and RSC. It was also noticed that alk. earth elements exceeded alkalies concn. and weak acids exceeded the strong acid element and HCO3-​was the predominant among anions, while Ca-​Mg dominates cations. Classification of water samples based on SAR and Salinity Hazard revealed that majority of the samples were under excellent (S1, 88.88​%) and excellent (C1, 80.56​%) to good (C2, 8.33​%) categories resp. Gibbs' ratio illustrates that majority of water samples fall in the pptn. dominance field, giving an indication that the aquifer recharging is by means of rain​/river water

Evaluation of Nutrient Index Using Organic Carbon, Available P and Available K Concentrations as a Measure of Soil Fertility in Varahi River Basin, India

Varahi River basin is in the midst of Udupi district in the western part of Karnataka state, covering parts of Kundapura and Udupi taluks in Udupi District, Karnataka, India. Spatial distributions for twenty physical and chemical properties were examined in the soil samples of selected agricultural fields in 28 different locations in Varahi River basin. The present study revealed that there is not much variation in soil fertility status of soils developed on various landforms in the area as the soils were having low to medium in organic carbon (0.06 to 1.20 %) and available nitrogen (6.27 to 25.09 Kg/ha) content; low to medium in available P (2.24 to 94.08 Kg/ha) and deficient to doubtful in available K (20.10 - 412.3 Kg/ha) contents. The soils of Varahi River basin were characterized as low-medium-low (LML) category based on the nutrient index calculated w.r.t. available organic carbon, available P and available K. Further, Sodium Absorption Ratio (SAR) and Exchangeable Sodium Percentage (ESP) indicated that the soils were excellent for irrigation

Environmental Impact of an Abandoned Composting Unit in Bangalore

Solid waste management still remains one of the most vicious problems to be resolved due to the lack of serious strategic efforts by the municipal authorities resulting into an existing inefficient, outdated and unscientific solid waste management system of Bangalore city. An abandoned composting unit, Karn ataka Compost Development Corporation (KCDC) has been selected to investigate the impact of leachate on groundwater and surface water source (Haralakunte Lake) in the vicinity of the unit. The characterization of leachate, surface water and groundwater sam ples revealed that the water reserves have been deteriorated by the percolation of untreated leachate. The spatial and temporal changes in the groundwater quality are shown with the aid of contour plots. The deterioration of groundwater quality is evident from the hydrochemical facies plotted using Piper and Durov diagrams showing a shift in the ionic composition which is further corroborated with the help of cluster analysis

Seasonal Variation of Fluoride, Nitrate and Boron in Ground Water of Hebbal and Challaghatta Basins, Bangalore, Karnataka

Present paper focuses on physico-chemical characteristics of Hebbal and Challaghatta basins, Bangalore with special reference to fluoride, nitrate and boron concentration. During the pre-monsoon of 2011, the NO^sub 3^^sup -^ content is as high as (100 mg/l) in 12% of wells having depth of less than 42 feet, whereas 88% of samples from wells having depth of more than 799 feet showed < 100 mg/l of NO^sub 3^^sup -^. The higher NO^sub 3^^sup -^ along shallow open wells is therefore attributed to sewage contamination. Pesticides and fertilizers used in agricultural activities are also contributing significant amounts of fluoride to the groundwater regime in Hebbal and Challaghatta aquifers. In the Hebbal and Challaghatta valleys, the industrial applications of boron that apparently could affect the groundwater system are washing powder and agricultural applications of boron-fertilizers and boron-pesticides. The high content of boron in several water sources is signal for restricting the use of washing powder containing boron

Multispectral Monitoring of Vegetation Cover of Bangalore Metropolitan Area

Urban vegetation plays significant role in one’s judgment for quality of place in a neighborhood, which is one of the important implication areas of urban image classification technique. In the present study Quick Bird and LISS III imageries of 2005 are used for comparative study of NDVI and TNDVI indices for estimating vegetation cover in Greater Bangalore also called Bruhat Bangalore Mahanagara Palike (BBMP) which is administratively divided into 8 zones. Both NDVI and TNDVI showed highly significant variation in their values between LISS III and Quick Bird imageries. The NDVI values range between -0.2 and 0.31797 in LISS III and –0.99595 and 0.92857 in Quick Bird. In case of TNDVI the variation is between 0 and 1.01145 for Quick Bird and 0 and 0.90442 for LISS III. A strong linear relationship was observed between NDVI and TNDVI of both imagery data set. The validation of results according to ground truth revealed that NDVI is much better tool for monitoring vegetation cover in urban environment in LISS III and Quick Bird data set. This study helps to demonstrate the difference between two imageries in depiction of the vegetation distribution across greater Bangalore. It also show the multipurpose utility of RS data for many application like land cover change, vegetation cover, planning and policy making, which are of particular importance in a large rapidly growing urban area with complex pattern of land use and many diverse environment

Land Cover Classification of Bangalore Metro Using Satellite Imageries-A Comparative Study

Land Use is an major element in temporal studies of urban imagery, its precise and revised information is indispensable for understanding the environmental consequences of corresponding changes. Impervious surface ratio (ISR) and green cover ratio (GCR are important elements in determining urban environments, which can be employed to assess urban flood phenomenon, vegetation percentage. In the current study temporal study of BBMP is made by procuring satellite imagery 0f 1992, 2000, 2005 and 2010. The imagery is classified into four classes like Water, Built ups, Vegetation and Others by superwised classification. . The overall classification accuracy of 90.56% was achieved for the four urban land cover types. The different imageries from 1992 to 2010 showed phenomenal variation in vegetation cover over the years. The Green cover shows initial increase from 1992 to 2000 and then we could observe rapid depletion from 2005 to 2010. The Impervious surface ratio shows more than 50% increase from 1992 to 2010 and the increase is more prominent in periphery of the city

Heavy Metals and Safety of Fresh Fruits in Bangalore City, India - A Case Study

Urban food security in India is a matter of growing concern. It is estimated that by 2005, 60% of India's population will be living in urban areas. The presence of heavy metals in human body always draws scientific concern as these are considered responsible for affecting health, especially in these days where the release of toxic wastes in the environment has been increased. The increasing trends in food contamination in urban areas are largely attributed to the polluted environment in urban agriculture, contaminated food transport and supply chains; poor market sanitary conditions, and the use of contaminated or waste water for irrigation purposes. The objectives of this paper to measure the levels of heavy metal contamination of fruits in Bangalore markets and assess how the heavy metal contamination might have impacted food safety standards vis a vis heavy metals on urban consumers. The results show that urban consumers are at greater risk of purchasing fresh fruits with high levels of heavy metals beyond the legally permissible limits as defined by the Indian Prevention of Food Adulteration Act, 1954. It must be noted here that these norms are less strict than international food safety norms like Codex Alimentarius or European Union standards. It is therefore suggested here that care should be taken in the following: reduce pollution at water source points; improve post harvest handling; enhance better coordination in fresh crops trading system to improve food safety standards; improve sanitary conditions for the city food markets; and increase awareness in consumers and policy makers on the dangers of heavy metal contamination in the food intake. Keywords: Heavy metals; Prevention of Food Adulteration Act; Atomic Absorption Spectrophotometer (AAS) DOI: 10.3126/kuset.v4i1.2880 Kathmandu University Journal of Science, Engineering and Technology Vol.4, No.1, September 2008, pp 17-2

Land Cover Dynamics of Devikulam Taluk-Understanding the Past Scenario

Monitoring land cover change is the most important step in decision making for local or government agencies. Specially for a forest recovery program, understanding of the past scenario of land cover is very essential. It is also very important to understand the past scenario of the land cover for identification of areas for afforestation programs in the country. In this study we have tried to understand the land cover trend before the start of 21st century. IRS LISS-I image of 1989 is the oldest high resolution imagery available, therefore land cover change from 1989. IRS LISS-II imageries for 1993 and 1997 were used by taking into account four year time interval. The imageries were digitally classified and compared to obtain the land cover change statistics. The exact areas were also identified by overlaying the classified imageries. It is observed that an area of about 23790 Ha out of 78721 Ha dense forest in the year 1989 was converted to other land cover category by 1997, which means about 27% of dense forest area was reduced to 19% by 1997. An increase in the built up class was also observed from 1000 Ha in 1989 to about 2074 Ha in 1997. This study has established that a major portion of the forested land were already degraded even before stringent forest Act came into existence. The land cover change pattern also helps in predicting the future land cover trends

Monitoring of Pesticide Residues in Farmgate Samples of Vegetables in Karnataka, India

Fifty Vegetable samples in Ramanagara district of Karnataka, India were analysed for 20 pesticide residues. Vegetable samples were extracted with acetonitrle and the pesticides are partitioned into petroleum ether and evaluated by gas liquid chromatography equipped with ECD and FTD. Recovery studies were performed at 0.1, 0.5 and 1.0 mg kg -1 fortification levels of each compound and the recoveries obtained ranged from 80.5% to 96.2% with relative standard deviations lower than 7%. The method showed good linearity over the range assessed 0.05-1.5mg kg -1 with correlation coefficient> 0.998 and the detection and quantification limits for the pesticides studied varied from 0.0001 to 0.044 mg kg -1 and 0.0005 to 0.0155 mg kg -1 , respectively. All the samples were found to be contaminated; the organo chlorines (83.5%) dominated followed by organophosphates (67%) and pyrethroids (55%). However, 34% of the samples were found to contain the residues of organophosphate insecticides above their respective maximum residue limits (MRL). It is therefore proposed to perform extensive monitoring studies covering all the vegetable crops from different agro-climatic regions of the state to know the exact status of pesticide contamination