Nanobiotechnology for the production of biofuels from spent tea

Bioenergy is the only alternative and cheap source of energy which can be made easily available to the world. The present experiment included three steps for the conversion of spent tea (Camellia sinensis) into biofuels. In the first step, spent tea was gasified using Co nano catalyst at 300°C and atmospheric pressure. Catalytic gasification of spent tea yielded 60% liquid extract, 28% fuel gases and 12% charcoal. Gaseous products contain 53.03% ethene, 37.18% methanol and 4.59% methane. In the second step of the experiment, liquid extract of spent tea obtained from gasification, on transesterification gave 40.79% ethyl ester (biodiesel). In the third step, Aspergillus niger’s growth on spent tea produced 57.49% bioethanol. This study reports an interesting finding that spent tea (solid waste) could be used not only for the production of biodiesel and bioethanol but also hydrocarbon fuel gases. The world today is consuming several million tons of tea yearly. The present technology could be utilized to produce alternate energy

New nanomaterial and process for the production of biofuel from metal hyper accumulator water hyacinth

Three different studies were performed for the conversion of water hyacinth (Eichhornia crassipes) plant into biofuel. In the first study, water hyacinth was saccharified with diluted sulfuric acid (1% v/v at 110°C for one hour), fermented by yeast (Saccharomyces cerevisiae). The results showed the formation of 55.20% ethanol and 41.66% acetic acid. In another experiment, water hyacinth was gasified by using Ni and Co nano catalysts at 50 - 400°C and atmospheric pressure. In catalytic gasification, CH4 (2.41 - 6.67%), C2H4 (19.74 - 45.52%), C3H4 (21.04 - 45.52%), CH3OH (1.43 - 24.67%), and C3H8 / CH3CHO (0.33 -26.09%) products were obtained. In this study, anatase form of titanium dioxide photocatalyst was used. The reaction was performed at room temperature which gives methane, methanol and ethanol.This study also reports an interesting finding that metal contaminated water hyacinth could be used for not only the production of biofuel but also hydrocarbons

Phytoremediation technologies for Ni++ by water hyacinth

Phytoremediation of metal contaminated soil and water by Eichhornia crassipes (water hyacinth) is promising. The study was conducted to compare the phytoremoval of Ni++ from soil and wastewater. For the measurement of phytoremoval from soil, E. crassipes was used in a pot experiment. Results showed the removal of (Ni) 24.23 μg/g dry weight of plant and large level calculations show removal of 3449.76 kg/ha of soil, corresponding to 25 μg/g of the added Ni++. In the second experiment, Ni++ contaminated Hoagland’s solution was used for the hydroponic growth of water hyacinth. The result of hydroponic experiment showed the phytoremoval of Ni++ from Ni++ contaminated wastewater; maximum removal was 1.954 μg/g of dry weight. In third experiment, ash of water hyacinth was used for the adsorption and desorption of Ni++. The adsorption capacity was 1.978 μg/g of ash. For the extraction(desorption) of Ni++, 3 M HNO3 was used. Desorption capacity was 3.71 μg/g of ash. The results of comparative study show order of nickel phytoremediation from soil to be greater than that from water by adsorption which was greater than that from water by hydroponic study. For phytoremoval of Ni++ from soil and water, water hyacinth plant and its ash showed excellence. The desorbed Ni++ can be used in the industries e.g. in Ni plating.Keywords: Nickel, phytoremediation, soil, waste water, water hyacinth, biosorptio

Utilisation of underwater acoustic backscatter systems to characterise nuclear waste suspensions remotely

This paper reports application of ABS (Acoustic Backscatter Systems) to address nuclear waste management within the UK. ABS offers a route towards an online monitoring system to characterise wastes safely and remotely in real-time, during pipeline transportation; resulting in reduced hazard reduction timescales and taxpayer cost savings. Here, an ultrasonic velocimetry profiler (UVP) was used to analyse glass dispersions of varying concentrations, to assess online waste monitoring applicability. Acoustic backscatter profiles were collected to establish attenuation coefficients for two glass sizes (∼40 and 80 µm) with 2 and 4 MHz probes. The 4 MHz probes were the most highly attenuating while transducer active radius had a negligible effect on probe sensitivity with either glass. A calibration procedure was used to measure sediment attenuation coefficients, which were compared to model estimates and experimental literature. For most systems, measured coefficients were close to estimated values, highlighting improved calibration accuracy, due to the mixing tank used. However, values for the smaller glass and 2 MHz probes overestimated model predictions, due to additional viscous attenuation. The measured value for the larger glass with 4 MHz probes was underestimated, this was caused by high attenuation reaching the instrument noise-floor, limiting the region available for analysis

Context and Crowding in Perceptual Learning on a Peripheral Contrast Discrimination Task: Context-Specificity in Contrast Learning

Perceptual learning is an improvement in sensitivity due to practice on a sensory task and is generally specific to the trained stimuli and/or tasks. The present study investigated the effect of stimulus configuration and crowding on perceptual learning in contrast discrimination in peripheral vision, and the effect of perceptual training on crowding in this task. 29 normally-sighted observers were trained to discriminate Gabor stimuli presented at 9° eccentricity with either identical or orthogonally oriented flankers with respect to the target (ISO and CROSS, respectively), or on an isolated target (CONTROL). Contrast discrimination thresholds were measured at various eccentricities and target-flanker separations before and after training in order to determine any learning transfer to untrained stimulus parameters. Perceptual learning was observed in all three training stimuli; however, greater improvement was obtained with training on ISO-oriented stimuli compared to CROSS-oriented and unflanked stimuli. This learning did not transfer to untrained stimulus configurations, eccentricities or target-flanker separations. A characteristic crowding effect was observed increasing with viewing eccentricity and decreasing with target-flanker separation before and after training in both configurations. The magnitude of crowding was reduced only at the trained eccentricity and target-flanker separation; therefore, learning for contrast discrimination and for crowding in the present study was configuration and location specific. Our findings suggest that stimulus configuration plays an important role in the magnitude of perceptual learning in contrast discrimination and suggest context-specificity in learning

Endothelial repair in stented arteries is accelerated by inhibition of Rho-associated protein kinase.

AIMS: Stent deployment causes endothelial cell (EC) denudation, which promotes in-stent restenosis and thrombosis. Thus endothelial regrowth in stented arteries is an important therapeutic goal. Stent struts modify local hemodynamics, however the effects of flow pertubation on EC injury and repair are incompletely understood. By studying the effects of stent struts on flow and EC migration we identified an intervention that promotes endothelial repair in stented arteries. METHODS AND RESULTS: In vitro and in vivo models were developed to monitor endothelialization under flow and the influence of stent struts. A 2D parallel-plate flow chamber with 100 μm ridges arranged perpendicular to the flow was used. Live cell imaging coupled to computational fluid dynamic simulations revealed that EC migrate in the direction of flow upstream from the ridges but subsequently accumulate downstream from ridges at sites of bidirectional flow. The mechanism of EC trapping by bidirectional flow involved reduced migratory polarity associated with altered actin dynamics. Inhibition of Rho-associated protein kinase (ROCK) enhanced endothelialization of ridged surfaces by promoting migratory polarity under bidirectional flow (p<0.01). To more closely mimic the in vivo situation we cultured EC on the inner surface of polydimethylsiloxane tubing containing Coroflex Blue stents (65 μm struts) and monitored migration. ROCK inhibition significantly enhanced EC accumulation downstream from struts under flow (p<0.05). We investigated the effects of ROCK inhibition on re-endothelialization in vivo using a porcine model of EC denudation and stent placement. En face staining and confocal microscopy revealed that inhibition of ROCK using fasudil (30 mg/day via osmotic minipump) significantly increased re-endothelialization of stented carotid arteries (p<0.05). CONCLUSIONS: Stent struts delay endothelial repair by generating localised bidirectional flow which traps migrating EC. ROCK inhibitors accelerate endothelial repair of stented arteries by enhancing EC polarity and migration through regions of bidirectional flow

Outcomes of 28+1 to 32+0 Weeks Gestation Babies in the State of Qatar: Finding Facility-Based Cost Effective Options for Improving the Survival of Preterm Neonates in Low Income Countries

In this retrospective study we did a comparative analysis of the outcome of 28+1 to 32+0 weeks gestation babies between the State of Qatar and some high income countries with an objective of providing an evidence base for improving the survival of preterm neonates in low income countries. Data covering a five year period (2002–2006) was ascertained on a pre-designed Performa. A comparative analysis with the most recent data from VON, NICHD, UK, France and Europe was undertaken. Qatar’s 28+1 to 32+0 weeks Prematurity Rate (9.23 per 1,000 births) was less than the UK’s (p < 0.0001). Of the 597 babies born at 28+1 to 32+0 weeks of gestation, 37.5% did not require any respiratory support, while 31.1% required only CPAP therapy. 80.12% of the MV and 96.28% of CPAP therapy was required for <96 hours. 86.1% of the mothers had received antenatal steroids. The 28+1 to 32+0 weeks mortality rate was 65.3/1,000 births with 30.77% deaths attributable to a range of lethal congenital and chromosomal anomalies. The survival rate increased with increasing gestational age (p < 0.001) and was comparable to some high income countries. The incidence of in hospital pre discharge morbidities in Qatar (CLD 2.68%, IVH Grade III 0.84%, IVH Grade IV 0.5%, Cystic PVL 0.5%) was less as compared to some high income countries except ROP ≥ Stage 3 (5.69%), which was higher in Qatar. The incidence of symptomatic PDA, NEC and severe ROP decreased with increasing gestational age (p < 0.05). We conclude that the mortality and in hospital pre discharge morbidity outcome of 28+1 to 32+0 weeks babies in Qatar are comparable with some high income countries. In two thirds of this group of preterm babies, the immediate postnatal respiratory distress can be effectively managed by using two facility based cost effective interventions; antenatal steroids and postnatal CPAP. This finding is very supportive to the efforts of international perinatal health care planners in designing facility-based cost effective options for low income countries

Utilisation of an operative difficulty grading scale for laparoscopic cholecystectomy

Background A reliable system for grading operative difficulty of laparoscopic cholecystectomy would standardise description of findings and reporting of outcomes. The aim of this study was to validate a difficulty grading system (Nassar scale), testing its applicability and consistency in two large prospective datasets. Methods Patient and disease-related variables and 30-day outcomes were identified in two prospective cholecystectomy databases: the multi-centre prospective cohort of 8820 patients from the recent CholeS Study and the single-surgeon series containing 4089 patients. Operative data and patient outcomes were correlated with Nassar operative difficultly scale, using Kendall’s tau for dichotomous variables, or Jonckheere–Terpstra tests for continuous variables. A ROC curve analysis was performed, to quantify the predictive accuracy of the scale for each outcome, with continuous outcomes dichotomised, prior to analysis. Results A higher operative difficulty grade was consistently associated with worse outcomes for the patients in both the reference and CholeS cohorts. The median length of stay increased from 0 to 4 days, and the 30-day complication rate from 7.6 to 24.4% as the difficulty grade increased from 1 to 4/5 (both p < 0.001). In the CholeS cohort, a higher difficulty grade was found to be most strongly associated with conversion to open and 30-day mortality (AUROC = 0.903, 0.822, respectively). On multivariable analysis, the Nassar operative difficultly scale was found to be a significant independent predictor of operative duration, conversion to open surgery, 30-day complications and 30-day reintervention (all p < 0.001). Conclusion We have shown that an operative difficulty scale can standardise the description of operative findings by multiple grades of surgeons to facilitate audit, training assessment and research. It provides a tool for reporting operative findings, disease severity and technical difficulty and can be utilised in future research to reliably compare outcomes according to case mix and intra-operative difficulty