145 research outputs found

    Technique for Immobilization of Lipase Within Membrane Pores as Nanoreactor

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    The objective of this study was to design of nanoscale biocatalyst system by utilizing the membrane as nanoporous media. The nanostructure was modified by two step methods: simple adsorption and continue with pressure driven filtration. Two types of polymeric membranes Mixed Cellulose Ester (MCE) and Polyethersulfone (PES) were used asmatrices for immobilization of lipase from Pseudomonas fluorescens. The lipase solution was allowed to permeate through the membrane and lipase molecule adsorbed on the inner wall of pores. The porosity and membrane matrices influenced the enzyme loading. The best result for enzyme loading inmembrane matric is 3.75 g.m-2 using PES membrane with incubation time of 18 hours. PES membrane was selected for further continuous transesterification studies. We evaluated the transesterification activity by converting triolein and methanol to methyl oleate and glycerol. The reaction was carried out in situ within the pores of membrane matric, so that its pores act kind of nanoreactor during formation of product material. The degree of triolein conversion using this kind of nanoreactor was about 80% with 30 minutes of residence time. The productivity of immobilized lipase within the pores were 40 fold higher than that of native free lipase

    Biomass Production Chlorella Vulgaris Buitenzorg Using Series of Bubble Column Photo Bioreactor with a Periodic Illumination

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    Chlorella vulgaris Buitenzorg cultivation using three bubble column photo bioreactors arranged in series with a volume of 200 mL for 130 hours shows an increase of biomass production of Chlorella vulgaris Buitenzorg up to 1.20 times and a decrease of the ability of CO2 fixation compared to single reactor at a periodic sun illumination cycle. The operation conditions on cultivation are as following: T, 29.0oC; P,1 atm.; UG, 2.40 m/h; CO2, 10%; Benneck medium; and illumination source by Phillip Halogen Lamp 20W /12V/ 50Hz. Other research parameters such as microbial carbon dioxide transferred rate (qco2), CO2 transferred rate (CTR), energy consumption for cellular formation (Ex), and cultural bicarbonate species concentration [HCO3] also give better results on series of reactor

    Integrated Nutrient Management for Natural Grasslands of Mid-Hills of Himalayas

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    Livestock rearing is an important pursuit in mountain farming in India and plays a crucial role throughout the country. The preponderance of marginal and small landholdings (about 82%) in hilly regions does not allow the farmers to allocate even a small part of their land exclusively for forage production. In Himachal Pradesh state of India about 1.16 m ha (20% of the total area) is under permanent pastures and other grazing lands and none of the natural grasslands are fertilised in any form. Existing grasslands have deteriorated to such an extent that their carrying capacity is only 1.05 ACU (Adult Cattle Unit, with an average body weight of 350 kg)/ha (Vashist et al., 2000). Biofertiliser-based technologies could be appropriate and cost effective approaches that are easy to adopt and eco-friendly. Response may arise from increased populations of phosphate solubilisers in the rhizosphere in P- deficient soils resulting in mobilisation of insoluble phosphorus (Raghu & Mac Rac, 1967). The study was undertaken with the main objectives of assessing the effects of biofertilisers on productivity and quality of natural grassland and the level of N and P substitution by biofertilisers

    The Consensus from the Mycobacterium avium ssp. paratuberculosis (MAP) Conference 2017.

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    On March 24 and 25, 2017 researchers and clinicians from around the world met at Temple University in Philadelphia to discuss the current knowledge of Mycobacterium avium ssp. paratuberculosis (MAP) and its relationship to human disease. The conference was held because of shared concern that MAP is a zoonotic bacterium that poses a threat not only to animal health but also human health. In order to further study this problem, the conferees discussed ways to improve MAP diagnostic tests and discussed potential future anti-MAP clinical trials. The conference proceedings may be viewed on the www.Humanpara.org website. A summary of the salient work in this field is followed by recommendations from a majority of the conferees

    Preventing and Treating Women’s Postpartum Depression: A Qualitative Systematic Review on Partner-Inclusive Interventions

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    Partner-related factors associated with the occurrence of Postpartum Depression (PPD) may justify the partner’s inclusion in preventive and treatment approaches. The aim of this qualitative systematic review was to synthesize the literature on partner-inclusive interventions designed to prevent or treat postpartum depression (PPD) in women. In accordance with the PRISMA guidelines, the systematic search of studies published between 1967 and May 2015 in PsycINFO and PubMed identified 26 studies that met the inclusion criteria, which reported on 24 interventions. The following partner parameters were analyzed: participation type, session content, mental health assessment, attendance assessment, and the effects of partner’s participation on the women’s response to the interventions. Total participation by the partner was mostly reported in the prevention studies, whereas partial participation was reported in the treatment studies. The session content was mostly based on psychoeducation about PPD and parenthood, coping strategies to facilitate the transition to parenthood such as the partner’s emotional and instrumental support, and problem-solving and communication skills. Some benefits perceived by the couples underscore the relevance of the partner’s inclusion in PPD interventions. However, the scarce information about the partner’s attendance and the associated effects on the women’s intervention outcomes, along with methodological limitations of the studies, made it difficult to determine if the partner’s participation was associated with the intervention’s efficacy. Conclusions about the clinical value of including partners in PPD interventions are still limited. More research is warranted to better inform health policy strategies

    Utilization of Bagasse Cellulose for Ethanol Production through Simultaneous Saccharification and Fermentation by Xylanase

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    Utilization of Bagasse Cellulose for Ethanol Production through Simultaneous Saccharification and Fermentation by Xylanase. Bagasse is a solid residue from sugar cane process, which is not many use it for some product which have more added value. Bagasse, which is a lignosellulosic material, be able to be use for alternative energy resources like bioethanol or biogas. With renewable energy resources a crisis of energy in Republic of Indonesia could be solved, especially in oil and gas. This research has done the conversion of bagasse to bioethanol with xylanase enzyme. The result show that bagasse contains of 52,7% cellulose, 20% hemicelluloses, and 24,2% lignin. Xylanase enzyme and Saccharomyces cerevisiae was used to hydrolyse and fermentation in SSF process. Variation in this research use pH (4, 4,5, and 5), for increasing ethanol quantity, SSF process was done by added chloride acid (HCl) with concentration 0.5% and 1% (v/v) and also pre-treatment with white rot fungi such as Lentinus edodes (L.edodes) as long 4 weeks. The SSF process was done with 24, 48, 72, and 96 hour’s incubation time for fermentation. Variation of pH 4, 4,5, and 5 can produce ethanol with concentrations 2,357 g/L, 2,451 g/L, 2,709 g/L. The added chloride acid (HCl) with concentration 0.5% and 1% (v/v) and L. edodes can increase ethanol yield, The highest ethanol concentration with added chloride acid (HCl) concentration 0.5% and 1% consecutively is 2,967 g/L, 3,249 g/L. The highest ethanol concentration with pre-treatment by L. edodes is 3,202 g/L

    Experimental Study of Incipient Motion in Mixed-size Sediment

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    Transport rates of five sediments were measured in a laboratory flume. Three of these sediments had the same mean size, the same size distribution shape, and different values of grain size distribution standard deviation. The critical shear stress for incipient motion of the individual size fractions within these sediments was estimated as that shear stress that produced a small dimensionless transport rate. The sorting of the sediment mixture had little effect on the critical shear stress of individual fractions, once the median size (D50) of the mixture and a fraction\u27s relative size (Di/D50) are accounted for. Our data, combined with previously published data, show a remarkably consistent relation between the critical shear stress of individual fractions and the fraction\u27s relative grain size, despite a broad variation in the available data of mixture sorting, grain size distribution shape, mean grain size, and grain shape. All fractions in a size mixture begin moving at close to the same value of bed shear stress during steady state transport conditions. This result is apparently true for transport systems where the transport rates of individual fractions are determined solely by the flow and bed sediment (recirculating systems), as well as for systems where the fractional transport rates are imposed on the system (feed systems). This equivalence in initial-motion results is important because natural transporting systems often show attributes of both types of behavior in an unknown combination
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