Differential inhibition of postnatal brain,spinal cord and body growth by a growth hormone antagonist

Background  

Growth hormone (GH) plays an incompletely understood role in the development of the central nervous system (CNS). In this study, we use transgenic mice expressing a growth hormone antagonist (GHA) to explore the role of GH in regulating postnatal brain, spinal cord and body growth into adulthood. The GHA transgene encodes a protein that inhibits the binding of GH to its receptor, specifically antagonizing the trophic effects of endogenous GH.     

Transfer measurements for the Ti+Ni systems at near barrier energies

Large enhancements have been observed in the sub-barrier fusion cross sections for Ti+Ni systems in our previous studies. Coupled channel calculations incorporating couplings to 2⁺ and 3⁻ states failed to explain these enhancements completely. A possibilty of transfer channels contributing to the residual enhancements had been suggested. In order to investigate the role of relevant transfer channels, measurements of one- and two-nucleon transfer were carried out for ^46,48Ti+⁶¹Ni systems. The present paper gives the results of these studies.     

Late-Stage Functionalization by Chan–Lam Amination: Rapid Access to Potent and Selective Integrin Inhibitors

A late-stage functionalization of the aromatic ring in amino acid derivatives is described. The key step is a copper-catalysed diversification of a boronate ester by amination (Chan–Lam reaction) that can be carried out on a complex β-aryl-β-amino acid scaffold. This not only considerably extends the substrate scope of amination partners, but also delivers an array of potent and selective integrin inhibitors as potential treatment agents of idiopathic pulmonary fibrosis (IPF). This versatile chemical strategy, which is amenable to high-throughput-array protocols, allows the installation of pharmaceutically valuable heteroaromatic fragments at a late stage by direct coupling to NH heterocycles, leading to compounds with drug-like attributes. It thus constitutes a useful addition to the medicinal chemist's repertoire.     

Using FTIR spectroscopy to detect sericin on historic silk

Silks represent some of the most precious ancient and historic textile artefacts in collections worldwide.Their optimum preservation demands an appreciation of their characteristics.One important concern,especially with regard to ancient Chinese silks,is whether the fabrics have been degummed.Silks with remnant sericin gum coating the fibroin fibres would require different conservation protocol.In previous research on aged silks,the presence of sericin has been inferred from amino acid analysis of hydrolysa...     

Iron-catalyzed Doyle-Kirmse reaction of allyl sulfides with (trimethylsilyl)diazomethane

[formula: see text] Iron salts efficiently catalyze the Doyle-Kirmse reaction of allyl sulfides with (trimethylsilyl)diazomethane and ethyl diazoacetate in dichloroethane at 83 degrees C. Competitive dimerization is less of a problem with (trimethylsilyl)diazomethane than with ethyl diazoacetate. Good results are obtained using only 1.5 equiv of (trimethylsilyl)diazomethane, even without slow addition. Phosphine ligands affect the kinetics, but not the diastereoselectivity. Dppe and BINAP lead to higher yields than dppp, but no enantioselection was detected with R-(+)-BINAP.     

Positively charged nanofiltration membranes: review of current fabrication methods and introduction of a novel approach

A review of the fabrication processes currently available to produce positively charged nanofiltration membranes has been conducted. The review highlights that there are few membranes and studies currently available. The preparation of a novel positively charged nanofiltration membrane is also described. This membrane was fabricated by surface modification of a prepared base membrane using polyethyleneimine followed by cross linking with butanedioldiglycidylether. The fabrication process uses standard organic solvents and avoids the need for hazardous materials, such as concentrated sulphuric acid, which significantly benefits the scale up potential of any future commercial manufacturing process. The new membrane was characterised using a number of state-of-the-art techniques, including a novel use of atomic force microscopy to determine pore size. Streaming potential measurements confirmed that this new membrane is indeed positively charged in the pH range below pH 9, which covers the majority of normal operating conditions. The performance characteristics for the new membrane were very favourable, with a pure water flux determined to be 20 LMH bar(-1) and a rejection of MgCl of 96%. Thus, this new membrane both adds to and complements the existing short supply of positively charged NF membranes and is suitable for applications such as the recovery of valuable cationic macromolecules in the bioprocess and pharmaceutical industries or removal of multi-valent cations such as dyes and heavy metals in the paper and pulp, textiles, nuclear, and automotive industries.     

Mechanical and electrical oscillations; transient and alternating electric currents

In the first part of the article a discussion on mechanical oscillation, both free and forced, serves to introduce the study of electrical oscillations, both transient and steadily alternating. The second part deals with power, power factor, Q, and other questions relating to alternating-current circuits.