Modelling Share Price Behaviour Across Time

The Efficient Markets Hypothesis (EMH) is currently the dominant paradigm in Finance. This paper reviews the theoretical development of the hypothesis and the empirical testing which has occurred to determine its validity. Furthermore, empirical anomalies found by researchers in the Weak Form of the EMH are discussed and their theoretical interpretation critiqued. This paper also provides an overview of the Hamilton (1989) model and its extensions, one of the many econometric models developed in order to model the non-linearity in time-series such as stock prices.

cGMP Recombinant FIX for IV and Oral Hemophilia B Therapy

Three specific aims are proposed: Specific Aim # 1. Process engineer and scale-up the recovery and purification of transgenic recombinant human Factor IX. The University of Nebraska-Lincoln Biological Process Development Facility will complete process development and scale-up, and produce clinical grade materials for preclinical studies. The endpoint is a proposed final product specification to help facilitate transfer to current Good Manufacturing Practices compliant production of clinical grade material to support an Investigational New Drug filing with the United States Food and Drug Administration (FDA) leading to clinical trials. Specific Aim #2. Characterize and formulate transgenic recombinant human Factor IX for intravenous dosage, and evaluate in a hemophilia B dog model. These activities are directed toward characterization of the product important to assure the provision of safe and reproducibly effective hemostasis. The results of these investigations will help support an IND filing with the FDA. Specific Aim # 3. Develop an oral dosage form of transgenic recombinant human Factor IX, and evaluate in hemophilia B mice and dog models. Oral administration of coagulation therapy will obviate the invasiveness, discomfort, potential for opportunistic infection, and complications of storage and supplies that accompany intravenous administration. Oral dosage forms of Factor IX will thus greatly increase the proportion of the patient population that can be treated. There is also published evidence suggesting that oral administration may reduce the potential for complicating immune responses to replacement therapy, especially in patients with severe hemophilia

Immobilization of Shewanella oneidensis MR-1 in diffusive gradients in thin films for determining metal bioavailability

Assessing metal bioavailability in soil is important in modelling the effects of metal toxicity on the surrounding ecosystem. Current methods based on diffusive gradient thin films (DGTs) and Gel-Integrated Microelectrode are limited in their availability and sensitivity. To address this, S. oneidensis, an anaerobic iron reducing bacterium, was incorporated into a thin layer of agarose to replace the polyacrylamide gel that is normally present in DGT to form biologically mobilizing DGT (BMDGT). Viability analysis revealed that 16-35% of the cells remained viable within the BMDGTs depending on the culturing conditions over a 20 h period with/without metals. Deployment of BMDGTs in standardized metal solutions showed significant differences to cell free BMDGTs when cells grown in Luria Broth (LB) were incorporated into BMDGTs and deployed under anaerobic conditions. Deployment of these BMDGTs in hematite revealed no significant differences between BMDGTs and BMDGTs containing heat killed cells. Whether heat killed cells retain the ability to affect bioavailability is uncertain. This is the first study to investigate how a microorganism that was incorporated into a DGT device such as the metal reducing bacteria, S. oneidensis, may affect the mobility of metals

Sampling and characterising groundwater nanoparticles in sub-oxic environments

Characterising nanoparticles is important for understanding physiochemical and biogeochemical processes occurring within groundwater bodies e.g. those impacted by the migration of leachates from waste storage sites as well as monitoring the use of engineered nanotechnology for pollution attenuation. While characterising nano-scale particles (both natural and engineered) within sub-oxic environments is a challenging task, it is critical for understanding pollution attenuation and migration within a number of different environments. The overall aim of this study was to develop a robust sampling and analytical methodology for characterising nanoparticles in sub-oxic environments using a range of complementary methods. This study has successfully sampled and characterised nano-scale particulate material in sub-oxic groundwaters within an alluvial floodplain aquifer impacted by a landfull plume. The integrity of the sample was maintained throughout the field and laboratory work to ensure that only nanoparticles representative of the sub-oxic environment were characterised. Nanoparticles from two pairs of nested boreholes were characterised by a number of state-of-the-art methods; atomic force microscopy (AFM), scanning electron microscopy (SEM), scanning transmisson electron microscopy (TEM) and field flow fractionation (FFF), to explore particle size distributions, morphology and surface chemistry. It is important to characterise nanoparticles in environmental contexts using multiple techniques as each method has its own benefits and limitations (Lead and Wilkinson 2006). As far as the authors are aware this is the first such study in the UK to isolate and characterise sub-oxic groundwater nanoparticles using these complimentary techniques. Groundwaters were found to have abundant iron and organic nanoparticles with diameters <30 nm. AFM results showed spherical nanoparticles with average diameters of ca 10 nm, while FFF with UV absorbance (254 nm) results indicated that smaller fulvic-like nanoparticles were present with average hydrodynamic diameters of ca. 1.5 nm. FFF with UV absorbance detection at 575 nm showed that another population of organic rich nanoparticles was present with larger hydrodynamic diameters (ca. 3 nm) in the groundwater at nest 26, but were not present in nest 28. These larger organic nanoparticles perhaps represent co-aggregated humic-like particles or another distinct type of organic matter. Scanning TEM analysis with energy-dispersive X-ray diffraction showed that Ca rich nanoparticles were present within the groundwater at a number of sites, and that P was associated with the surface of Fe rich particles in nest 28. Aeration of sub-oxic samples resulted in a dramatic shift in the nanoparticle size distribution. This was a result of the aggregation of smaller nanoparticles to form larger agglomerations with diameters typically >50-100 nm. This is analogous to processes that occur during groundwater aeration for water treatment, and mixing of anaerobic and aerobic environmental waters, e.g. during rapid recharge events, flooding, hyporheic zone mixing, waste water treatment and waste water inputs to surface waters. The techniques developed in this study have potential wider applications for understanding the occurrence and fate of natural and anthropogenic (engineered) nanoparticles in sub-oxic conditions, such as the fate of nanoparticles injected for pollution attenuation, those found below landfill sites, within waste water treatment works and the hyporheic zone which are all important redox hot-spots for pollution attenuation and biological activity

Effects of engineered silver nanoparticles on the growth and activity of ecologically important microbes

Summary: Currently, little is known about the impact of silver nanoparticles (AgNPs) on ecologically important microorganisms such as ammonia-oxidizing bacteria (AOB). We performed a multi-analytical approach to demonstrate the effects of uncapped nanosilver (uAgNP), capped nanosilver (cAgNP) and Ag2SO4 on the activities of the AOB: Nitrosomonas europaea, Nitrosospira multiformis and Nitrosococcus oceani, and the growth of Escherichia coli and Bacillus subtilis as model bacterial systems in relation to AgNP type and concentration. All Ag treatments caused significant inhibition to the nitrification potential rates (NPRs) of Nitrosomonas europaea (decreased from 34 to cAgNP>uAgNP. In conclusion, AgNPs (especially cAgNPs) and Ag2SO4 adversely affected AOB activities and thus have the potential to severely impact key microbially driven processes such as nitrification in the environment

Bioavailability of nanoscale metal oxides TiO(2), CeO(2), and ZnO to fish

addresses: The Hatherly Laboratories, University of Exeter, Prince of Wales Road, Exeter EX4 4PS, UK.types: Journal Article; Research Support, Non-U.S. Gov'tCopyright © 2010 American Chemical Society. Post print version of article deposited. The final published version is available from: http://dx.doi.org/10.1021/es901971aNanoparticles (NPs) are reported to be a potential environmental health hazard. For organisms living in the aquatic environment, there is uncertainty on exposure because of a lack of understanding and data regarding the fate, behavior, and bioavailability of the nanomaterials in the water column. This paper reports on a series of integrative biological and physicochemical studies on the uptake of unmodified commercial nanoscale metal oxides, zinc oxide (ZnO), cerium dioxide (CeO(2)), and titanium dioxide (TiO(2)), from the water and diet to determine their potential ecotoxicological impacts on fish as a function of concentration. Particle characterizations were performed and tissue concentrations were measured by a wide range of analytical methods. Definitive uptake from the water column and localization of TiO(2) NPs in gills was demonstrated for the first time by use of coherent anti-Stokes Raman scattering (CARS) microscopy. Significant uptake of nanomaterials was found only for cerium in the liver of zebrafish exposed via the water and ionic titanium in the gut of trout exposed via the diet. For the aqueous exposures undertaken, formation of large NP aggregates (up to 3 mum) occurred and it is likely that this resulted in limited bioavailability of the unmodified metal oxide NPs in fish