Anionic migration reactions in aromatic systems effected by collisional activation : Deprotonated anilides containing methoxycarbonyl substituents

Long-range cross-ring reactions are of minor importance in the collision-induced mass spectra (MS/MS) of [M - H]- ions of CH2OCO-C6H4-NHCOR systems: e.g. the loss of 'CD3CO2CH3' from CH3OCO-C6H4-(N) over bar COCD3. Major processes involve (i) losses of radicals to form stable radical anions, e.g. loss of a ring hydrogen atom and losses from the ester (CH3 ., CH3O . and . CO2CH3), (ii) losses of neutral molecules from the amide moiety [e.g. CO (R = H) and CH2CO (R = CH3), and proximity effects when the two substituents are ortho [e.g. loss of (CH3OD+CO2) from o-CH3OCO-C6H4 (N) over bar COCD3].

Tandem mass spectrometry of deprotonated iodothyronines

In order to assist with the development of more selective and sensitive methods for thyroid hormone analysis the \[M-H](-) anions of the iodothyronines T4, T3, rT3, (3,5)-T2 and the non-iodinated thyronine (TO) have been generated by negative ion electrospray mass spectrometry. Tandem mass spectra of these ions were recorded on a triple-quadrupole mass spectrometer and show a strong analogy with the fragmentation pathways of the parent compound, tyrosine. All iodothyronines also show significant abundances of the iodide anion in their tandem mass spectra, which represents an attractive target for multiple reaction monitoring (MRM) analysis, given that iodothyronines are the only iodine bearing endogenous molecules. Characteristic fragments are observed at m/z 359.7 and 604.5 for rT3 but are absent in the spectrum of T3, thus differentiating the two positional isomers. The striking difference in the fragmentation patterns of these regioisomeric species is attributed to the increased acidity of the phenol moiety in rT3 compared with T3. Copyright (C) 2005 John Wiley & Sons, Ltd.

Potential interstellar molecules : Formation of neutral C6CO from C6CO- in the gas phase

Computations at the RCCSD(T)/aug-cc-pVDZ//B3LYP/6-31G* level of theory indicate that neutral C6CO is a stable species. The ground state of this neutral is the singlet cumulene oxide :C=C=C=C=C=C=C=O. The adiabatic electron affinity and dipole moment of singlet C6CO are 2.47 eV and 4.13 D, respectively, at this level of theory. The anion (C6CO)(-.) should be a possible precursor to this neutral. It has been formed by an unequivocal synthesis in the ion source of a mass spectrometer by the S(N)2(Si) reaction between (CH3)(3)Si-C=C-C=C-C=C-CO-CMe3 and F- to form C-=C-C=C-C=C-CO-CMe3 which loses Me3C in the source to form C6CO-.. Charge stripping of this anion by vertical Franck-Condon oxidation forms C6CO, characterised by the neutralisation-reionisation spectrum (-NR+) of C6CO-., which is stable during the timeframe of this experiment (10(-6) s), Copyright (C) 2000 John Wiley & Sons, Ltd.

The fragmentation pathways of protonated Amiton in the gas phase : towards the structural characterisation of organophosphorus chemical warfare agents by electrospray ionisation tandem mass spectrometry

Amiton (O,O-diethyl-S-[2-(diethylamino)ethyl]phosphorothiolate), otherwise known as VG, is listed in schedule 2 of the Chemical Weapons Convention (CWC) and has a structure closely related to VX (O-ethyl-S-(2-diisopropylamino)ethylmethylphosphonothiolate). Fragmentation of protonated VG in the gas phase was performed using electrospray ionisation ion trap mass spectrometry (ESI-ITMS) and revealed several characteristic product ions. Quantum chemical calculations provide the most probable structures for these ions as well as the likely unimolecular mechanisms by which they are formed. The decomposition pathways predicted by computation are consistent with deuterium-labeling studies. The combination of experimental and theoretical data suggests that the fragmentation pathways of VG and analogous organophosphorus nerve agents, such as VX and Russian VX, are predictable and thus ESI tandem mass spectrometry is a powerful tool for the verification of unknown compounds listed in the CWC. Copyright (c) 2006 Commonwealth of Australia. Published by John Wiley & Sons, Ltd.

Direct detection of additives and degradation products from polymers by liquid extraction surface analysis employing chip-based nanospray mass spectrometry

RATIONALE: Polymer-based surface coatings in outdoor applications experience accelerated degradation due to exposure to solar radiation, oxygen and atmospheric pollutants. These deleterious agents cause undesirable changes to the aesthetic and mechanical properties of the polymer, reducing its lifetime. The use of antioxidants such as hindered amine light stabilisers (HALS) retards these degradative processes; however, mechanisms for HALS action and polymer degradation are poorly understood. METHODS: Detection of the HALS TINUVINW123 (bis(1-octyloxy-2,2,6,6-tetramethyl-4-piperidyl) sebacate) and the polymer degradation products directly from a polyester-based coil coating was achieved by liquid extraction surface analysis (LESA) coupled to a triple quadrupole QTRAPW 5500 mass spectrometer. The detection of TINUVINW123 and melamine was confirmed by the characteristic fragmentation pattern observed in LESA-MS/MS spectra that was identical to that reported for authentic samples. RESULTS: Analysis of an unstabilised coil coating by LESA-MS after exposure to 4 years of outdoor field testing revealed the presence of melamine (1,3,5-triazine-2,4,6-triamine) as a polymer degradation product at elevated levels. Changes to the physical appearance of the coil coating, including powder-like deposits on the coating's surface, were observed to coincide with melamine deposits and are indicative of the phenomenon known as polymer ' blooming'. CONCLUSIONS: For the first time, in situ detection of analytes from a thermoset polymer coating was accomplished without any sample preparation, providing advantages over traditional extraction-analysis approaches and some contemporary ambient MS methods. Detection of HALS and polymer degradation products such as melamine provides insight into the mechanisms by which degradation occurs and suggests LESA-MS is a powerful new tool for polymer analysis. Copyright (C) 2012 John Wiley & Sons, Ltd.

Fragmentation pathways of 2,3-dimethyl-2,3-dinitrobutane cations in the gas phase

2,3-Dimethyl-2,3-dinitrobutane (DMNB) is an explosive taggant added to plastic explosives during manufacture making them more susceptible to vapour-phase detection systems. In this study, the formation and detection of gas-phase \[M+H](+), \[M+Li](+), \[M+NH(4)](+) and \[M+Na](+) adducts of DMNB was achieved using electrospray ionisation on a triple quadrupole mass spectrometer. The \[M+H](+) ion abundance was found to have a strong dependence on ion source temperature, decreasing markedly at source temperatures above 50 degrees C. In contrast, the \[M+Na](+) ion demonstrated increasing ion abundance at source temperatures up to 105 degrees C. The relative susceptibility of DMNB adduct ions toward dissociation was investigated by collision-induced dissociation. Probable structures of product ions and mechanisms for unimolecular dissociation have been inferred based on fragmentation patterns from tandem mass (MS/MS) spectra of source-formed ions of normal and isotopically labelled DMNB, and quantum chemical calculations. Both thermal and collisional activation studies suggest that the \[M+Na](+) adduct ions are significantly more stable toward dissociation than their protonated analogues and, as a consequence, the former provide attractive targets for detection by contemporary rapid screening methods such as desorption electrospray ionisation mass spectrometry. Copyright (C) 2009 Commonwealth of Australia. Published by John Wiley & Sons, Ltd.

Production and isolation of ligated metal(IV)-oxo ions by tandem mass spectrometry

High valent metal(IV)-oxo species, \[M(=O)(Melm)(n)(OAc)](+) (M = Mn-Ni, MeIm = 1-methylimidazole, n = 1-2), which are relevant to biology and oxidative catalysis, were produced and isolated in gas-phase reactions of the metal(II) precursor ions \[M(MeIm)(n)(OAc)](+) (M = Mn-Zn, n = 1-3) with ozone. The precursor ions \[M(MeIm)(OAc)](+) and \[M(MeIm)(2)(OAc)](+) were generated via collision-induced dissociation of the corresponding \[M(MeIm)(3)(OAc)](+) ion. The dependence of ozone reactivity on metal and coordination number is discussed. Copyright (C) 2010 John Wiley & Sons, Ltd.

Identifying factors that promote consumer behaviours causing expired domestic food waste

Many commentators argue that domestic food waste is strongly influenced by consumer behaviours. This article reports on a study using mixed-methods to identify key factors responsible for promoting consumer behaviours that lead to domestic food waste through the lens of the Value-Belief-Norm (VBN) theory. Based on the study’s findings, three factors are proposed that cause behaviours that lead to food waste: supply knowledge – does a consumer know what food they have available; location knowledge – does a consumer know where to locate food items, and; food literacy – to what degree do past experience and acquired knowledge impact on a consumer’s food consumption and wastage practices. We analyse the study’s findings in light of a review of literature about consumer food wastage behaviours and in turn, present new insights into consumer behaviour, food waste, and the use of technology to reduce food waste.

Reflections on tomorrow’s menu : evidence for inpatient meal preferences at a large tertiary public hospital

There are limited studies that describe patient meal preferences in hospital; however this data is critical to develop menus that address satisfaction and nutrition whilst balancing resources. This quality study aimed to determine preferences for meals and snacks to inform a comprehensive menu revision in a large (929 bed) tertiary public hospital. The method was based on Vivanti et al. (2008) with data collected by two final year dietetic students. The first survey comprised 72 questions, achieved a response rate of 68% (n = 192), with the second more focused at 47 questions achieving a higher response rate of 93% (n = 212). Findings showed over half the patients reporting poor or less than normal appetite, 20% describing taste issues, over a third with a LOS >7 days, a third with a MST _ 2 and less than half eating only from the general menu. Soup then toast was most frequently reported as eaten at home when unwell, and whilst most reported not missing any foods when in hospital (25%), steak was most commonly missed. Hot breakfasts were desired by the majority (63%), with over half preferring toast (even if cold). In relation to snacks, nearly half (48%) wanted something more substantial than tea/coffee/biscuits, with sandwiches (54%) and soup (33%) being suggested. Sandwiches at the evening meal were not popular (6%). Difficulties with using cutlery and meal size selection were identified as issues. Findings from this study had high utility and supported a collaborative and evidenced based approach to a successful major menu change for the hospital.

Let them eat steak : food preferences of patients in a tertiary public hospital

Information on foods patients like and dislike is the essential basis for planning menus which are acceptable to patients and promote adequate consumption. The aim of this study was to obtain quantitative data on the food preferences of inpatients at a large metropolitan public hospital for use in menu planning. Methodology was based on a study by Williams et al (1988), and included additional questions about appetite and taste changes. The survey used a 9 point hedonic scale to rate foods listed in random order and was modified to incorporate more contemporary foods than those used in the originalWilliams study. Surveys were conducted by final year University of Queensland dietetics students on Food Service Practicum at the Royal Brisbane and Women’s Hospital (929 beds) in 2012. The first survey (220 questions, n = 157) had a response rate of 61%. The second included more sandwich fillings and salads (231 questions, n = 219, response rate 67%). Total number surveyed was 376. Results showed the most preferred foods were roast potato, grilled steak, ice cream, fresh strawberries, roast lamb, roast beef, grapes and banana. The least preferred foods were grapefruit, soybeans, lentils, sardines, prune juice and grapefruit juice. Patients who reported taste changes (10%) had similar food preferences to those who didn’t report taste changes. Patients who reported poor/very poor appetite (10%) generally scored foods lower than those who reported OK (22%), good/very good appetite (65%). The results of this study informed planning for a new patient menu at the RBWH in December 2012.

Innovations in dietetic training in foodservice management : can early exposure to practice enhance final year competency development?

Student engagement in the delivery of theoretical course materials is a current challenge in the tertiary sector including for dietetic training. In 2011 with the creation of a new nutritionist position for Queensland Meals on Wheels (QMOW), a service learning approach to support this organisation was used with third year dietetic students undertaking two days of structured activities at various QMOW sites in South East Queensland, aligned with coursework in Foodservice Management (FSM). This cohort of students was then followed in their final year post successful completion of five weeks professional practice in FSM to see if this experience supported readiness for placement and competency development. Evaluation was undertaken of eligible students (n = 50) via paper based survey (response rate 94%) with all participating in targeted focus groups. Findings showed that students acknowledged the QMOW experience (on reflection 14 months later) providing opportunity for participation and/or observation in 5 of 12 FSM areas taught in third year, including food safety, meal production, assembly, delivery and dishwashing. Over half the students identified good exposure to FSM competency areas during the QMOW experience, with 83% satisfied with their competency exposure and subsequent practice during final year placements. A consistent theme emerged from focus groups supporting inclusion of practical opportunities with the theoretical component of the FSM subject to highlight relevance to learning. These findings highlight the importance of such teaching initiatives to met student learning preferences, linking theory with practice and supporting competency development in the final year of training programs.

Pushing cultural competence boundaries in nutrition and dietetics training

A health workforce ready for safe practice is a government priority, and particularly critical to support indigenous communities closing ‘the gap’. Increased pressure exists on dietetic training programs for quality placements, with fewer opportunities for immersion in Aboriginal and Torres Strait Islander communities to demonstrate cultural competence. In 2012, Queensland University of Technology established a partnership with Apunipima Cape York Health Council with 56 weeks of dietetic placement for 8 students provided to achieve these aims. Clinical practice in Community Public Health Nutrition (CPHN) was structured in a standard 6 week placement, with Individual Case Management (ICM) and Foodservice Management (FSM) integrated across 8 weeks (4 each), with an additional 2 weeks ICM prior in a metropolitan indigenous health service. Students transitioned from urban to rural then remote sites, with new web-based technologies used for support. Strong learning opportunities were provided, with CPHN projects in antenatal and child health, FSM on standardisation of procedures in a 22 bed health facility, and ICM exposing students to a variety of cases via hospital in/outpatients, general clinics and remote community outreach. Supervisor focus group evaluation was positive, with CPHN and FSM enhancing capacity of service. Student focus group evaluation revealed placements exceeded expectations, with rating high, and strong confidence in cultural competence described. Students debriefed final and third year cohorts on their experiences, with increased awareness and enthusiasm for work with indigenous communities indicated by groups. With the success of this partnership, placements are continuing 2013, and new boundaries in dietetic training established.

Sharpening our tools – translating research into practice

Providing culturally appropriate health communication tools at a community level, whilst meeting funding objectives set by Government led initiatives, can be challenging. Literature states that a translational research framework fostering community communication can encourage the development of appropriate communication tools to facilitate transfer of health information between community and researchers. Reflections from initial Need for Feed cooking and nutrition education program trials in remote Indigenous communities across Cape York indicated program resources were neither meeting community nor researchers needs. In response, a translational research framework was modelled with collaborative partnerships formed between researchers and community with the aim of modifying current resources. Local working groups were established to facilitate communication and guide continual remodelling and retrial of resources for successive programs. Feedback from working groups indicated community members wanted resources with more pictures and less words. Partnership with Chronic Disease Resources Online (CDRO) led to the development of pictorial resources including 3 evaluation tools, 27 recipe sets and 10 education support materials. Between June to December 2012 resources were trialled across 4 Cape York communities with 69 school aged children and 4 community elders. Qualitative data has indicated high satisfaction with modified pictorial resources, proving pictorial resources to be an effective and culturally appropriate method to both communicate health messages to community and facilitate flow of evaluation data to researchers. A translational research framework fostering communication between community and researchers can potentially enhance the quality of health communication tools.

Superoxide does react with peroxides : direct observation of the haber-weiss reaction in the gas phase

The fact that nature provides specific enzymes to selectively remove superoxide (O2.−) from aerobic organisms, namely, the superoxide dismutase enzymes,1 has led to the suggestion that this radical ion may cause the oxidative damage associated with degradative disease and aging.2 Intriguingly, however, superoxide itself is relatively unreactive toward most cellular components, which suggests that dismutase enzymes may ultimately protect the cell against more pernicious oxidants formed from superoxide. As such, there is increasing interest in the endogenous chemistry of superoxide and the pathways by which it might beget more reactive oxygen species. Protonation of superoxide to form the hydroperoxyl radical (HOO.) and dismutation of the same species to hydrogen peroxide (HOOH), with subsequent metal-catalyzed reduction to the hydroxyl radical (HO.), are well-characterized processes in which both the HOO. and HO. radicals are significantly more reactive than their common progenitor.2 Recent examples, however, have also linked superoxide to the putative production of singlet oxygen3 and ozone,4, 5 although the definitive characterization of these chemistries in the cellular milieu has proved challenging

Construction of interstellar cumulenes and heterocumulenes : Mass spectrometric studies

The last few years have brought an increasing interest in the chemistry of rite interstellar and circumstellar environs. Many of the molecular species discovered in remote galactic regions have been dubbed 'non-terrestrial' because of their unique structures (Thaddeus et al, 1993). These findings have provided a challenge to chemists in many differing fields to attempt to generate these unusual species in the laboratory of particular recent interest have been the unsaturated hydrocarbon families, CnH and CnH2, which have been pursued by a number of diverse methodologies. A wine range of heterocumulenes, including CnO, HCnO, CnN, HCnN, CnS, HCnS, CnSi and HCnSi have also provided intriguing targets for laboratory experiments. Strictly the term cumulene refers to a class of compounds that possess a series of adjacent double bonds, with allene representing the simplest example (H2C=C=CH2). However for many of the non-terrestrial molecules presented here, the carbon chain cannot be described in terms of a single simple valence structure, and so we use the terms cumulene and heterocumulene in a more general sense: to describe molecular species that contain an unsaturated polycarbon chain. Mass spectrometry has proved an invaluable tool in the quest for interstellar cumulenes and heterocumulenes in the laboratory it has the ability in its many forms, to (i) generate charged analogs of these species in the gas phase, (ii) probe their connectivity, ion chemistry, and thermochemistry, and (iii) in some cases, elucidate the neutrals themselves. Here, we will discuss the progress of these studies to this time. (C) 1999 John Wiley & Sons, Inc.