The low bearing capacity of expansive soils often results in serviceability issues and premature failures of infrastructure built upon them. Various studies have demonstrated the use of different soil treatment methods using mechanical or chemical approaches to stabilize the weak ground as a precaution. Most of the reported studies are limited to either lab-based investigations or field monitoring works without the scientific connection between theory and translation. This study aims to verify the field application of a novel soil stabilization method by conducting laboratory-controlled experiments and field performance testing as verification. Enzyme-based soil stabilization was adopted for in-situ clay soil in combination with ordinary portland cement as a sustainable stabilization approach. Soil samples were collected at different regions from the field to evaluate the effectiveness and the mechanism of soil stabilization in the field by the means of replicating stabilization at the laboratory scale using identical mixing proportions of the additives. The mechanical behavior of stabilized soil was assessed through the unconfined compression strength and California bearing ratio test methods. In addition, the changes in the chemical composition of the soil due to the additives were evaluated through the X-ray diffraction testing technique and microporosity test using 2D images translated to 3D profiles from X-ray micro CT tomography. The efficacy of field stabilization was evaluated by conducting the falling weight deflectometer test in the stabilized site. Results from the study are useful to understand the efficacy of field soil stabilization and enhance the reliability of enzyme-based stabilization in practice.

There are numerous manuals to guide practitioners in utilizing traditional additives in the construction of road, rail and dam construction but they fall short of specific guidance for non-standard additive-based ecofriendly and cost-effective soil stabilization. Increased attention has recently been on the use of non-standard additives for stabilizing weak soils due to environmental and cost concerns associated with traditional additives. We summarize the specific guidelines of using environmental-friendly enzymes to treat weak soils. We elaborate on the requirements and specifications for the Eko-Soil multi-enzyme product that is manufactured from water and proteins extracted from fermented exudes of plants. Specific tests (laboratory and field) and conditions required for soil stabilization using Eko-Soil enzyme are elaborated using the experience of past construction projects. The guide also elaborates enhancing the efficiency of enzymatic soil stabilization by correctly incorporating the required mixing proportions and pre-requisite condition tests. Professionals and practitioners will benefit from using novel eco-friendly sustainable stabilization techniques in the treatment of weak soils covering many applications including roads, foundations, water containment areas, landfills, working platforms and slope erosion control.

Object of present investigation was to develop and characterize such a gastroretentive tablet, which provides the synergism effect of adhesiveness and floating property for prolonged release of 5-flourouracil within the stomach. The floating mucoadhesive tablets were prepared by the wet granulation method using different ratios of hydroxy propyl methyl cellulose (HPMC K4MCR) and Carbopol 934P as polymers. The prepared floating-mucoadhesive tables were characterized for hardness, detachment stress, floating properties, swelling index and surface morphology by SEM. The in vitro drug release and floating behaviour were studied in simulated gastric fluid (SGF) at pH 1.2. Different kinetic models for drug release were as well applied. Formulations of T-9 batch were furthermore subjected to stability and in vivo radiographic studies.

The prime object of this study was to develop such a film which could float on gastric content releasing the 5-fluorouracil (5-FU) in nearby region for local action in stomach. These films may provide better retentivity of drug in the stomach. 5-FU loaded floating films were prepared by solvent casting technique employing mercury as substrate and cellulose acetate as film forming polymer. The films were evaluated for weight uniformity, thickness, drug content uniformity, floating characteristics, and in vitro drug release. To access the in vivo floating characteristic albino rabbits were used for radio imaging. The thickness of film was found to be ranging from 0.341 ± 0.110 to 0.717 ± 0.031 mm. Maximum floating lag time was 142.6 ± 2.41 s. The floating films were found to be floated up to maximum period of 23.65 ± 0.86 h. Cumulative % drug release was found to be ranging from 85 to 99 %. All optimized formulations were also subjected to release kinetics study.

Multiple-unit-type oral floating hollow microspheres of 5-fluorouracil (5-Fu) were developed using modified solvent evaporation technique to prolong gastric residence time, to target stomach cancer, and to increase drug bioavailability. The prepared microspheres were characterized for micromeritic properties, floating behavior, entrapment efficiency, and scanning electron microscopy (SEM). The in vitro drug release and floating behavior were studied in simulated gastric fluid (SGF) at pH 1.2. The yield of microspheres was obtained up to84.46±6.47%. Microspheres showed passable flow properties. Based on optical microscopy, particle size was found to be ranging from158.65±12.02to198.67±17.45 μm. SEM confirmed spherical size, perforated smooth surface, and a hollow cavity inside the microspheres. Different kinetic models for drug release were also applied on selected batches.

To explore the impact of rising atmospheric CO2 concentration [CO2] and temperature on yield, nutritional quality and phosphorus (P) requirement of wheat in subtropical India, wheat was grown in growth chambers under two levels of [CO2]: ambient (AC) and elevated (EC) (650 ppm); two levels of temperature: ambient (AT) and elevated (ET) (ambient + 3 degrees C); and three levels of P fertilization: 0, 100 and 200% of recommended dose. Under the most realistic scenario of concurrently elevated CO2 and temperature (ECT), wheat yield was reduced by 17% while grain protein, Zn and Fe concentrations were reduced by 9%, 24% and 20%, respectively. Although, higher P doses partially compensated the yield reduction caused by ECT, decline in nutritional quality (protein, Zn and Fe) was further aggravated at higher P doses. Despite the decline in yield and quality of wheat under ECT, total P uptake increased by 17%, whereas P utilization efficiency was reduced by 30.4%. Overall, our results indicate the likely reduction in yield and nutritional quality, and increase in P requirement of wheat under rising [CO2] and temperature in subtropical India.