Effects of insect herbivores on early successional habitats

Imperial Users onl

Assessment of DAF-19 Related Behavioral Defects

The daf-19 gene encodes the only RFX transcription factors in C. elegans, producing at least four related protein isoforms, one of which, DAF-19C, is responsible for ciliogenesis. Previous work by Senti and Swoboda (2008) demonstrated that adult worms deficient in all four DAF-19 proteins have extremely aberrant dwelling and roaming behavior on bacterial food. Most intriguingly, the addition of cDNA encoding the DAF-19C isoform restores cilia formation, but does not fully restore wild-type dwelling and roaming behavior. We are suggesting that additional neuron functions are needed to properly execute behaviors and these neuron functions require the activity of other DAF-19 isoforms. We have tested this hypothesis using both classic assays of roaming behavior and a newly developed assay that mimics a patchy food environment to further probe worm foraging behavior. We are assessing the behavior of worms lacking all isoforms of DAF-19 as well as those containing mutant alleles that affect only the larger isoforms of DAF-19 to determine whether these isoforms play a role in nervous system function and worm behavior

The Electroanalytical Performance of Sonogel Carbon Titanium (IV) Oxide Electrodes versus Conducting Polymer Electrodes in the Electrochemical Detection of Biological Molecules

The electrochemical performance of a newly developed sonogel carbon titanium (IV) oxide (SGC/TiO2 ) electrode against poly(3-methylthiophene) (P3MT) and poly(2,2\u27-bithiophene) (PBTP) modified electrodes in the electrochemical detection of biological molecules is reported. The stability of the Titanium (IV) Oxide coating on the sonogel carbon electrode was shown to be greater than the P3MT coating on the conventional size glassy carbon electrode. After 10 consecutive scans, there was a 21% loss of the initial signal at the P3MT modified electrode and a 5% loss of the initial signal at the SGC/TiO2 electrode. The influence of NAD+ on NADH response was tested. The PBTP modified electrode and bare electrode demonstrated the inability to stabilize the interference due to NAD+. The SGC/TiO2 electrode was able to detour the susceptibility to interfering NAD+. The response potential was improved by 141 mV. Response time for 5mM catechol (CAT) and 5mM ascorbic acid (AA) in 0.01M sulfuric acid was determined. Specificity for CAT detection was measured using a 5mM CAT + 5mM AA mixture in 0.01M sulfuric acid. The SGC/TiO2 electrode permits a shorter response time and improved selectivity for CAT. NADH was irreversible in all electrolytes. Highest anodic peak potential, at the PBTP modified electrode, was measured in sodium nitrate. Highest anodic peak potential at the SGC/TiO2 electrode was recorded in sulfuric acid

The Pan American World Airways-National Airlines Merger and The Airline Deregulation Act of 1978: AHistory and Analysis

Fifteen months after Texas International Airlines surprised the commercial aviation community by announcing it had purchased 9.2 percent of the common stock of National Airlines,\u27 the Civil Aeronautics Board [C.A.B.] unanimously approved not only Texas International\u27s merger application, but also the subsequently-filed Pan American World Airways-National Airlines merger applicatio

Applications of Capillary Electrophoresis for Studying Serum Albumin Enantioselection of D,L-Tryptophan Analogs

The pharmacokinetic difference between drug enantiomers is the impetus for developing analytical techniques to assess enantiomeric purity. Capillary electrophoresis (CE) is an analytical technique that is used for characterizing drug-protein binding. The pitfall to using CE for drug-protein binding studies is protein chiral selectors tend to adsorb onto capillary walls and cause changes in electroosmotic flow that lead to decreased enantioselection and migration time irreproducibility between consecutive injections. The experimental parameters for minimizing the adverse effects of protein adsorption are not clear from the literature. Rinsing protocols to improve enantioselection and migration time repeatability were developed using the tryptophan-bovine serum albumin system as a model. The enantioselection of bovine serum albumin (BSA) could be improved by: 1) increasing separation voltage; 2) using sample buffer ionic strength at least 3 orders of magnitude less than the separation buffer; 3) limiting the equilibration time with separation buffer; and 4) allowing for protein diffusion. Rinsing the capillary with sodium hydroxide, followed by water improved migration time repeatability RSD from 24.7% to 1.8% (n = 4). Drug-protein binding is contingent upon the three dimensional structure of the binding site, and the presence of other competing drug molecules. Drug-drug displacement is difficult to predict and the effects of protein glycation on binding of drugs is not well defined. To highlight the use of CE for addressing questions of biochemical interest, CE was applied to characterize drug-drug displacement and the effects of protein glycation on the enantioselection of drugs by BSA. The tryptophan-bovine serum albumin, 5-fluoro-tryptophan-bovine serum albumin, and 5-hydroxy-tryptophan-bovine serum albumin systems were used as models. A CE method for studying competitive binding was established using ibuprofen as the displacer molecule. Accurate calculation of selectivity was found to depend on the precomplexation of ibuprofen and BSA. A CE method for studying the effects of protein glycation was developed using BSA containing different degrees of glycation as chiral selectors. The enantioselection of tryptophan analogs by BSA was altered by glycation as reported in other analytical methods. These studies can serve as guidelines for optimizing serum albumin enantioselection and extending its use in other biopharmaceutical applications

Bail in the Time of COVID-19

The COVID-19 pandemic that began in early 2020 resulted in changes to both the form and content of bail hearings and reviews within Ontario. While the statutory framework contained within sections 515, 520, 525 and 679 of the Criminal Code remained unchanged, practical changes were necessary in order to allow bail matters to occur virtually and safely. Initially, the existence of COVID-19 may have allowed for the release of some accused persons who would not have been let out on bail prior to the pandemic. By early 2021, bail courts appear to have settled into a pattern where the COVID-19 pandemic could be a factor that could lead to release, usually under the tertiary grounds in clause 515(10)(c) of the Criminal Code, for any particular defendant, as long as some medical evidence, specific to that accused, could be presented to the court

WAS FAIR FAIR TO U.S. CORN GROWERS? AN ANALYSIS OF THE PAYMENTS OFFERED TO CORN GROWERS UNDER THE 1996 FEDERAL AGRICULTURAL IMPROVEMENT AND REFORM ACT

The 1996 Farm Bill (FAIR) dramatically changed agricultural policy for producers of many commodities. A series of 7 annual decoupled payments replaced the deficiency-payment program. Option-pricing techniques are used to determine whether program benefits to corn producers are smaller or larger under the new program than the old.Agricultural and Food Policy,

The role of feedback in shaping the structure of the interstellar medium

We present an analysis of the role of feedback in shaping the neutral hydrogen (H I) content of simulated disc galaxies. For our analysis, we have used two realizations of two separate Milky Way-like (similar to L star) discs - one employing a conservative feedback scheme (McMaster Unbiased Galaxy Survey), the other significantly more energetic [Making Galaxies In a Cosmological Context (MaGICC)]. To quantify the impact of these schemes, we generate zeroth moment (surface density) maps of the inferred H I distribution; construct power spectra associated with the underlying structure of the simulated cold interstellar medium, in addition to their radial surface density and velocity dispersion profiles. Our results are compared with a parallel, self-consistent, analysis of empirical data from The H I Nearby Galaxy Survey (THINGS). Single power-law fits (P proportional to k(gamma)) to the power spectra of the stronger feedback (MaGICC) runs (over spatial scales corresponding to similar to 0.5 to similar to 20 kpc) result in slopes consistent with those seen in the THINGS sample (gamma similar to -2.5). The weaker feedback (MUGS) runs exhibit shallower power-law slopes (gamma similar to -1.2). The power spectra of the MaGICC simulations are more consistent though with a two-component fit, with a flatter distribution of power on larger scales (i.e. gamma similar to -1.4 for scales in excess of similar to 2 kpc) and a steeper slope on scales below similar to 1 kpc (gamma similar to -5), qualitatively consistent with empirical claims, as well as our earlier work on dwarf discs. The radial H I surface density profiles of the MaGICC discs show a clear exponential behaviour, while those of the MUGS suite are essentially flat; both behaviours are encountered in nature, although the THINGS sample is more consistent with our stronger (MaGICC) feedback runs