Electron Detachment Dissociation,and Collision-Induced Dissociation of Polyamidoamine (PAMAM) Dendrimer Ions with Amino, Amidoethanol, and Sodium Carboxylate Surface Groups

Here, we investigate the effect of the structure (generation) and nature of the surface groups of different polyamidoamine (PAMAM) dendrimers on electron-mediated dissociation, either electron capture dissociation (ECD) or electron detachment dissociation (EDD), and compare the fragmentation with that observed in collision-induced dissociation (CID). ECD and EDD of the PAMAM dendrimers esulted in simple mass spectra, which are straightforward to interpret, whereas CID produced complex mass spectra. The results show that electron-mediated dissociation (ECD and EDD) of PAMAM dendrimers does not depend on the nature of the surface group but tends to occur within the innermost generations. CID of the PAMAM dendrimers showed a strong dependence on the nature of the surface group and occurred mostly in the outer generation. The results demonstrate the potential utility of ECD and EDD as a tool for the structural analysis of PAMAM dendrimers

Top-Down Mass Analysis of Protein Tyrosine Nitration: Comparison of Electron Capture Dissociation with “Slow-Heating” Tandem Mass Spectrometry Methods

Tyrosine nitration in proteins is an important post-translational modification (PTM) linked to various pathological conditions. When multiple potential sites of nitration exist, tandem mass spectrometry (MS/MS) methods provide unique tools to locate the nitro-tyrosine(s) precisely. Electron capture dissociation (ECD) is a powerful MS/MS method, different in its mechanisms to the “slow-heating” threshold fragmentation methods, such as collision-induced dissociation (CID) and infrared multiphoton dissociation (IRMPD). Generally, ECD provides more homogeneous cleavage of the protein backbone and preserves labile PTMs. However recent studies in our laboratory demonstrated that ECD of doubly charged nitrated peptides is inhibited by the large electron affinity of the nitro group, while CID efficiency remains unaffected by nitration. Here, we have investigated the efficiency of ECD versus CID and IRMPD for top-down MS/MS analysis of multiply charged intact nitrated protein ions of myoglobin, lysozyme, and cytochrome c in a commercial Fourier transform ion cyclotron resonance (FT-ICR) mass spectrometer. CID and IRMPD produced more cleavages in the vicinity of the sites of nitration than ECD. However the total number of ECD fragments was greater than those from CID or IRMPD, and many ECD fragments contained the site(s) of nitration. We conclude that ECD can be used in the top-down analysis of nitrated proteins, but precise localization of the sites of nitration may require either of the “slow-heating” methods

Determinants Of Unionisation For Part-Time Women Employees In Australian Banks

Against the declining trend of Australian employees to join unions, unionisation of part-time female employees in the banking industry is relatively strong. For the finance and insurance industry in 2001, 30.3% of total part-time female employees were unionised compared to 25% of full-time female employees and 17.2% of full-time male employees. Overall, 22.3% of employees from this industry were members (ABS, 2002). Under freedom of association, what can influence an individual's decision to unionise? A survey was conducted on three major Australian banks in August 2000. We use a binary choice regression model to analyse personal and union-organising characteristics that significantly influence individual's decision to unionise. Previous membership under union preference provisions and earning relatively high wages would lead to a higher probability to join the union. Union's role in enterprise bargaining and whether union did anything to recruit have significant impact on individual decisions. Thus, part-time female employees are not unwilling to join when they recognise the need for job protection.

Tissue, cell type and stage-specific ectopic gene expression and RNAi induction in the Drosophila testis

The Drosophila testis has numerous advantages for the study of basic cellular processes, as production of sperm requires a highly orchestrated and complex combination of morphological changes and developmentally regulated transitions. Experimental genetics using Drosophila melanogaster has advanced dramatically with the advent of systems for ectopic expression of genetic elements in specific cells. However the genetic tools used in Drosophila research have rarely been generated with the testes in mind, and the utility of relatively few systems has been documented for this tissue. Here I will summarize ectopic expression systems that are known to work for the testis, and provide advice for selection of the most appropriate expression system in specific experimental situations

ORCID EPrints Implementation Survey Analysis

This report explores the results of a survey of users on their requirements and plans for integrating ORCID functionality into EPrints repository software. The community was invited to share their use cases, and an online survey based on this information was conducted to determine the priorities and needs of the wider community

The Message of the Rose

https://digitalcommons.library.umaine.edu/mmb-me/1601/thumbnail.jp

The Wnt receptor Ryk is a negative regulator of mammalian dendrite morphogenesis

This work was supported by the National Health and Medical Research Council (NHMRC) of Australia (Grants 1061512, 1063080). ML and KS were supported by an Australian Postgraduate Award or a University of Queensland International Scholarship, respectively. Imaging work was performed in the Queensland Brain Institute’s Advanced Microscopy Facility and generously supported by an ARC LIEF grant (LE130100078). We thank Assoc. Prof. Julian Heng (Harry Perkins Institute of Medical Research, Perth, Australia) for providing the pCA-ß-EGFPm5-Silencer 3 vector, Prof. Joseph LoTurco (University of Connecticut, USA) for the piggyBAC vector, and Prof. Steven Stacker (Peter MacCallum Cancer Centre, Melbourne, Australia) for providing the Ryk knockout mice and the full-length Ryk plasmid. We are also grateful to Mr Luke Hammond for expert advice on microscopy and Ms Rowan Tweedale for critical reading of the manuscript.Peer reviewedPublisher PD

On the centrality of tenure in spatial data systems for coastal/marine management: International exemplars versus emerging practice in Ireland

Although it is often overlooked, access to data regarding ‘tenure’ is of primary importance in underpinning coastal management and marine spatial planning (MSP). National, regional and international coastal/marine spatial data management exemplars demonstrate the need for clarity and certainty with respect to legal coastal/marine geographies (i.e. the basis for achieving security of tenure). Good practice in MSP is underpinned by four key pillars (use’, ‘value’, ‘development’ and ‘tenure’ (U,V,D,T)). The exemplars demonstrate the importance of currency in the statutory delineation of the coastline (HWM) and the spatial extent of the ‘coastal zone’ and tenure therein.The National Marine Planning Framework (NMPF), established in Ireland in 2021, provides the foundations for three of the interrelated management (U,V,D) pillars but those relating to ‘tenure’ are largely absent. Coastal/marine management platforms and data gateways have yet to be fully developed to meet emerging marine/offshore obligations while national data portals remain primarily terrestrial in focus. Early steps to create a MSP ‘one stop’ web portal (MarinePlan.ie) are rather limited when benchmarked against international exemplars that do include information related to tenure. This is particularly important as legislation enacting the adoption of the NMPF extends planning control and the marine consent authorisations process of Irish Coastal Local Authorities (CLAs) to also include the nearshore (three nautical miles seaward from High Water Mark (HWM)). To achieve MSP targets, information on coastal/marine legal and regulatory interests across the land/sea interface needs to match that currently available in terrestrial settings