Parsimonious Kernel Fisher Discrimination

By applying recent results in optimization transfer, a new algorithm for kernel Fisher Discriminant Analysis is provided that makes use of a non-smooth penalty on the coefficients to provide a parsimonious solution. The algorithm is simple, easily programmed and is shown to perform as well as or better than a number of leading machine learning algorithms on a substantial benchmark. It is then applied to a set of extreme small-sample-size problems in virtual screening where it is found to be less accurate than a currently leading approach but is still comparable in a number of cases

Analysis of the distal urinary tract in larval and adult zebrafish reveals homology to the human system

Little is known about the distal excretory component of the urinary tract in Danio rerio (zebrafish). This component is affected by many human diseases and disorders of development. Here, we have undertaken multi-level analyses to determine the structure and composition of the distal urinary tract in the zebrafish. In silico searches identified uroplakin 1a (ukp1a), uroplakin 2 (upk2) and uroplakin 3b (upk3b) genes in the zebrafish genome (orthologues to genes that encode urothelium-specific proteins in humans). In situ hybridization demonstrated ukp1a expression in the zebrafish pronephros and cloaca from 96 h post-fertilization. Haematoxylin and Eosin staining of adult zebrafish demonstrated two mesonephric ducts uniting into a urinary bladder that leads to a distinct urethral opening. Immunohistochemistry identified Uroplakin 1a, Uroplakin 2 and GATA3 expression in zebrafish urinary bladder cell layers that match human urothelial expression. Fluorescent dye injections demonstrated zebrafish urinary bladder function, including urine storage and intermittent micturition, and a urethral orifice separate from the larger anal canal and rectum. Our findings reveal homology between the urinary tracts of zebrafish and humans, and offer the former as a model system to study disease

Codes of Fair Competition: The National Recovery Act, 1933-1935, and the Women’s Dress Manufacturing Industry

Controversial issues prevalent in today’s ready-to-wear apparel industry include the right of workers to join unions, the proliferation of sweatshops and sweatshop conditions, and design piracy. The idea of forming codes of conduct to establish criteria of ethical business practices is not new to the apparel industry. Indeed, the women’s dress manufacturing industry discussed and debated codes of fair competition under the New Deal Policies of the National Recovery Act (NRA) of 1933 to 1935. Primary sources for this study included governmental hearings in the establishment of the NRA Dress Code, The New York Times, Women’s Wear Daily, and the Journal of the Patent Office Society. The history of the NRA codes implemented in the U.S. women’s ready-to-wear apparel industry provides an important case study highlighting the difficulties and complexities of creating and achieving industry-wide standard practices through self-regulation. The failure of the NRA demonstrates that even with the joint cooperation of industry, labor, and consumer groups and the backing of the force of law, codes of fair competition proved impossible to enforce

Optimisation of a fluorimetric assay for the screening of potential alpha-glucosidase inhibitors in coloured plant extracts and foods

The frequently used method for the in vitro screening of inhibitors of yeast α-glucosidase is based on the hydrolysis of p-nitrophenol-α-D-glucopyranoside to yield p-nitrophenol and glucose. After adjusting to pH 8 to form the yellow nitrophenolate anion, the absorbance at 405 nm is measured [1,2]. During our investigations into potential α-glucosidase inhibitors from sugarcane products, we found a decrease in sensitivity when highly coloured extracts were assayed. Therefore, an optimised method of the α-glucosidase assay was developed, using the fluorogenic substrate 4-methylumbelliferyl-α-D-glucopyranoside (4-MUG), to ensure a more reproducible and reliable screening tool for highly coloured plant extracts and foods. The optimised conditions for the assay were determined: α-glucosidase (2mU/mL), 4-MUG (84µM), incubation time (20 minutes), incubation temperature (37°C) and assay buffer pH (5.5). A molasses extract was screened for α-glucosidase inhibition using the optimised conditions with 80% inhibition seen at 150µg/mL and no negative quenching effects at concentrations within the linear range of the instrument. The optimised assay was also used to determine IC50 values for acarbose and fucoidan. The results suggest that acarbose does inhibit yeast α-glucosidase, which contradicts earlier work [3]. Overall, this optimised assay will be a valuable tool for the screening of highly coloured plant extracts and foods for α-glucosidase activity