The mental health of Australians bereaved during the first two years of the COVID-19 pandemic: a latent class analysis.

BACKGROUND: The COVID-19 pandemic disrupted many areas of life, including culturally accepted practices at end-of-life care, funeral rites, and access to social, community, and professional support. This survey investigated the mental health outcomes of Australians bereaved during this time to determine how these factors might have impacted bereavement outcomes. METHODS: An online survey indexing pandemic and bereavement experiences, levels of grief, depression, anxiety, and health, work, and social impairment. Latent class analysis (LCA) was used to identify groups of individuals who shared similar symptom patterns. Multinomial regressions identified pandemic-related, loss-related, and sociodemographic correlates of class membership. RESULTS: 1911 Australian adults completed the survey. The LCA identified four classes: low symptoms (46.8%), grief (17.3%), depression/anxiety (17.7%), and grief/depression/anxiety (18.2%). The latter group reported the highest levels of health, work, and social impairment. The death of a child or partner and an inability to care for the deceased due to COVID-19 public health measures were correlated with grief symptoms (with or without depression and anxiety). Preparedness for the person's death and levels of pandemic-related loneliness and social isolation differentiated all four classes. Unemployment was associated with depression/anxiety (with or without grief). CONCLUSIONS: COVID-19 had profound impacts for the way we lived and died, with effects that are likely to ricochet through society into the foreseeable future. These lessons learned must inform policymakers and healthcare professionals to improve bereavement care and ensure preparedness during and following future predicted pandemics to prevent negative impacts.

CELPI: trial protocol for a randomised controlled trial of a Carer End of Life Planning Intervention in people dying with dementia.

BACKGROUND: Dementia is a leading cause of death in developed nations. Despite an often distressing and symptom laden end of life, there are systematic barriers to accessing palliative care in older people dying of dementia. Evidence exists that 70% of people living with severe dementia attend an emergency department (ED) in their last year of life. The aim of this trial is to test whether a Carer End of Life Planning Intervention (CELPI), co-designed by consumers, clinicians and content specialists, improves access to end of life care for older people with severe dementia, using an ED visit as a catalyst for recognising unmet needs and specialist palliative care referral where indicated. METHODS: A randomised controlled trial (RCT) enrolling at six EDs across three states in Australia will be conducted, enrolling four hundred and forty dyads comprising a person with severe dementia aged ≥ 65 years, and their primary carer. Participants will be randomly allocated to CELPI or the control group. CELPI incorporates a structured carer needs assessment and referral to specialist palliative care services where indicated by patient symptom burden and needs assessment. The primary outcome measure is death of the person with dementia in the carer-nominated preferred location. Secondary outcomes include carer reported quality of life of the person dying of dementia, hospital bed day occupancy in the last 12 months of life, and carer stress. An economic evaluation from the perspective of a health funder will be conducted. DISCUSSION: CELPI seeks to support carers and provide optimal end of life care for the person dying of dementia. This trial will provide high level evidence as to the clinical and cost effectiveness of this intervention. TRIAL REGISTRATION: ACTRN12622000611729 registered 22/04/2022.

Quantifying SIMS of Organic Mixtures and Depth Profiles-Characterizing Matrix Effects of Fragment Ions.

Sets of matrix factors, Ξ, are reported for the first time for secondary ions in secondary ion mass spectrometry for several binary organic systems. These show the interplay of the effects of ion velocity, fragment chemistry, and the secondary ion point of origin. Matrix factors are reported for negative ions for Irganox 1010 with FMOC or Irganox 1098 and, for both positive and negative ions, with Ir(ppy)2(acac). For Irganox 1010/FMOC, the Ξ values for Irganox 1010 fall with m/z, whereas those for FMOC rise. For m/z < 250, Ξ scales very approximately with (m/z)0.5, supporting a dependence on the ion velocity at low mass. Low-mass ions generally have low matrix factors but |Ξ| may still exceed 0.5 for m/z < 50. Analysis of ion sequences with addition or loss of a hydrogen atom shows that the Ξ values for Irganox 1010 and FMOC ions change by - 0.026 and 0.24 per hydrogen atom, respectively, arising from the changing charge transfer rate constant. This effect adds to that of velocity and may be associated with the nine times more hydrogen atoms in the Irganox 1010 molecule than in FMOC. For Irganox 1098/Irganox 1010, the molecular similarity leads to small |Ξ|, except for the pseudo molecular ions where the behavior follows Irganox 1010/FMOC. For Ir(ppy)2(acac)/Irganox 1010, the positive secondary ions show twice the matrix effects of negative ions. These data provide the first overall assessment of matrix factors in organic mixtures necessary for improved understanding for quantification and the precise localization of species. Graphical Abstract ᅟ.

SIMS of Organic Materials-Interface Location in Argon Gas Cluster Depth Profiles Using Negative Secondary Ions.

A procedure has been established to define the interface position in depth profiles accurately when using secondary ion mass spectrometry and the negative secondary ions. The interface position varies strongly with the extent of the matrix effect and so depends on the secondary ion measured. Intensity profiles have been measured at both fluorenylmethyloxycarbonyl-L-pentafluorophenylalanine (FMOC) to Irganox 1010 and Irganox 1010 to FMOC interfaces for many secondary ions. These profiles show separations of the two interfaces that vary over some 10 nm depending on the secondary ion selected. The shapes of these profiles are strongly governed by matrix effects, slightly weakened by a long wavelength roughening. The matrix effects are separately measured using homogeneous, known mixtures of these two materials. Removal of the matrix and roughening effects give consistent compositional profiles for all ions that are described by an integrated exponentially modified Gaussian (EMG) profile. Use of a simple integrated Gaussian may lead to significant errors. The average interface positions in the compositional profiles are determined to standard uncertainties of 0.19 and 0.14 nm, respectively, using the integrated EMG function. Alternatively, and more simply, it is shown that interface positions and profiles may be deduced from data for several secondary ions with measured matrix factors by simply extrapolating the result to Ξ = 0. Care must be taken in quoting interface resolutions since those measured for predominantly Gaussian interfaces with Ξ above or below zero, without correction, appear significantly better than the true resolution. Graphical Abstract ᅟ.

Determination of the sputtering yield of cholesterol using Arn(+) and C60(+(+)) cluster ions.

The sputtering yield of cholesterol films on silicon wafers is measured using Arn(+) and C60(+(+)) ions in popular energy (E) and cluster size (n) ranges. It is shown that the C60(+(+)) ions form a surface layer that stabilizes the film so that a well-behaved profile is obtained. On the other hand, the Arn(+) gas clusters leave the material very clean but, at room temperature, the layer readily restructures into molecular bilayers, so that, although a useful measure may be made of the sputtering yield, the profiles become much more complex. This restructuring does not occur at room temperature normally but results from the actions of the beams in the sputtering process for profiling in secondary ion mass spectrometry. Better profiles may be made by reducing the sample temperature to -100 °C. This is likely to be necessary for many lower molecular weight materials (below 1000 Da) to avoid the movement of molecules. Measurements for cholesterol films on 37 nm of amiodarone on silicon are even better behaved and show the same sputtering yields at room temperature as those films directly on silicon at -100 °C. The yields for both C60(+(+)) and Arn(+) fit the Universal Equation to a standard deviation of 11%.

Sampling Depths, Depth Shifts, and Depth Resolutions for Bi(n)(+) Ion Analysis in Argon Gas Cluster Depth Profiles.

Gas cluster sputter depth profiling is increasingly used for the spatially resolved chemical analysis and imaging of organic materials. Here, a study is reported of the sampling depth in secondary ion mass spectrometry depth profiling. It is shown that effects of the sampling depth leads to apparent shifts in depth profiles of Irganox 3114 delta layers in Irganox 1010 sputtered, in the dual beam mode, using 5 keV Ar2000⁺ ions and analyzed with Bi(q+), Bi3(q+) and Bi5(q+) ions (q = 1 or 2) with energies between 13 and 50 keV. The profiles show sharp delta layers, broadened from their intrinsic 1 nm thickness to full widths at half-maxima (fwhm's) of 8-12 nm. For different secondary ions, the centroids of the measured delta layers are shifted deeper or shallower by up to 3 nm from the position measured for the large, 564.36 Da (C33H46N3O5⁻) characteristic ion for Irganox 3114 used to define a reference position. The shifts are linear with the Bi(n)(q+) beam energy and are greatest for Bi3(q+), slightly less for Bi5(q+) with its wider or less deep craters, and significantly less for Bi(q+) where the sputtering yield is very low and the primary ion penetrates more deeply. The shifts increase the fwhm's of the delta layers in a manner consistent with a linearly falling generation and escape depth distribution function (GEDDF) for the emitted secondary ions, relevant for a paraboloid shaped crater. The total depth of this GEDDF is 3.7 times the delta layer shifts. The greatest effect is for the peaks with the greatest shifts, i.e. Bi3(q+) at the highest energy, and for the smaller fragments. It is recommended that low energies be used for the analysis beam and that carefully selected, large, secondary ion fragments are used for measuring depth distributions, or that the analysis be made in the single beam mode using the sputtering Ar cluster ions also for analysis.

Sputtering Yields for Mixtures of Organic Materials Using Argon Gas Cluster Ions.

The sputtering yield volumes of binary mixtures of Irganox 1010 with either Irganox 1098 or Fmoc-pentafluoro-L-phenylalanine (FMOC) have been measured for 5 keV Ar2000(+) ions incident at 45° to the surface normal. The sputtering yields are determined from the doses to sputter through various compositions of 100 nm thick, intimately mixed, layers. Because of matrix effects, the profiles for secondary ions are distorted, and profile shifts in depth of 15 nm are observed leading to errors above 20% in the deduced sputtering yield. Secondary ions are selected to avoid this. The sputtering yield volumes for the mixtures are shown to be lower than those deduced from a linear interpolation from the pure materials. This is shown to be consistent with a simple model involving the changing energy absorbed for the sputtering of intimate mixtures. Evidence to support this comes from the secondary ion data for pairs of the different molecules. Both binary mixtures behave similarly, but matrix effects are stronger for the Irganox 1010/FMOC system.

Depth resolution at organic interfaces sputtered by argon gas cluster ions: the effect of energy, angle and cluster size.

An analysis is presented of the effect of experimental parameters such as energy, angle and cluster size on the depth resolution in depth profiling organic materials using Ar gas cluster ions. The first results are presented of the incident ion angle dependence of the depth resolution, obtained at the Irganox 1010 to silicon interface, from profiles by X-ray photoelectron spectrometry (XPS). By analysis of all relevant published depth profile data, it is shown that such data, from delta layers in secondary ion mass spectrometry (SIMS), correlate with the XPS data from interfaces if it is assumed that the monolayers of the Irganox 1010 adjacent to the wafer substrate surface have an enhanced sputtering rate. SIMS data confirm this enhancement. These results show that the traditional relation for the depth resolution, FWHM = 2.1Y(1/3) or slightly better, FWHM = P(X)Y(1/3)/n(0.2), where n is the argon gas cluster size, and P(X) is a parameter for each material are valid both at the 45° incidence angle of the argon gas cluster sputtering ions used in most studies and at all angles from 0° to 80°. This implies that, for optimal depth profile resolution, 0° or >75° incidence may be significantly better than the 45° traditionally used, especially for the low energy per atom settings required for the best resolved profiles in organic materials. A detailed analysis, however, shows that the FWHM requires a constant contribution added in quadrature to the above such that there are minimal improvements at 0° or greater than 75°. A critical test at 75° confirms the presence of this constant contribution.

Improving secondary ion mass spectrometry C60(n+) sputter depth profiling of challenging polymers with nitric oxide gas dosing.

Organic depth profiling using secondary ion mass spectrometry (SIMS) provides valuable information about the three-dimensional distribution of organic molecules. However, for a range of materials, commonly used cluster ion beams such as C60(n+) do not yield useful depth profiles. A promising solution to this problem is offered by the use of nitric oxide (NO) gas dosing during sputtering to reduce molecular cross-linking. In this study a C60(2+) ion beam is used to depth profile a polystyrene film. By systematically varying NO pressure and sample temperature, we evaluate their combined effect on organic depth profiling. Profiles are also acquired from a multilayered polystyrene and polyvinylpyrrolidone film and from a polystyrene/polymethylmethacrylate bilayer, in the former case by using an optimized set of conditions for C60(2+) and, for comparison, an Ar2000(+) ion beam. Our results show a dramatic improvement for depth profiling with C60(2+) using NO at pressures above 10(-6) mbar and sample temperatures below -75 °C. For the multilayered polymer film, the depth profile acquired using C60(2+) exhibits high signal stability with the exception of an initial signal loss transient and thus allows for successful chemical identification of each of the six layers. The results demonstrate that NO dosing can significantly improve SIMS depth profiling analysis for certain organic materials that are difficult to analyze with C60(n+) sputtering using conventional approaches/conditions. While the analytical capability is not as good as large gas cluster ion beams, NO dosing comprises a useful low-cost alternative for instruments equipped with C60(n+) sputtering.

Ambient surface mass spectrometry using plasma-assisted desorption ionization: effects and optimization of analytical parameters for signal intensities of molecules and polymers.

Results are presented on the optimization and characterization of a plasma-assisted desorption ionization (PADI) source for ambient mass spectrometry. It is found that by optimizing the geometry we can increase ion intensities for valine and by tuning the plasma power we can also select a more fragmented or less fragmented spectrum. The temperature of the surface rises linearly with plasma power: at 19 W it is 71 °C and at 28 W it is 126 °C. To understand if the changes in signal intensity are related to thermal desorption, experiments using a temperature-controlled sample stage and low plasma power settings were conducted. These show markedly different signal intensities to experiments of equivalent surface temperature but higher plasma power, proving that the mechanisms of ionization and desorption are more complicated than just thermal processes. Four different polymers, poly(methyl methacrylate) (PMMA), poly(ethylene terephthalate) (PET), poly(lactic acid) (PLA), and poly(tetrafluoroethylene) (PTFE), are analyzed using PADI. Mass spectra are obtained from all the polymers in the negative ion mode and from PMMA and PLA in the positive ion mode. For each polymer, characteristic ions are identified showing the ability to identify materials. The ions are formed from bond cleavage with O and CH(2) as common adducts. Ions were detected up to m/z 1200 for PTFE.

Surface analysis using a new plasma assisted desorption/ionisation source for mass spectrometry in ambient air.

The authors report on a modified micro-plasma assisted desorption/ionisation (PADI) device which creates plasma through the breakdown of ambient air rather than utilising an independent noble gas flow. This new micro-PADI device is used as an ion source for ambient mass spectrometry to analyse species released from the surfaces of polytetrafluoroethylene, and generic ibuprofen and paracetamol tablets through remote activation of the surface by the plasma. The mass spectra from these surfaces compare favourably to those produced by a PADI device constructed using an earlier design and confirm that the new ion source is an effective device which can be used to achieve ambient mass spectrometry with improved spatial resolution.

A drunk and disorderly country: a nationwide cross-sectional survey of alcohol use and misuse in Great Britain.

OBJECTIVES: To explore current alcohol drinking patterns, behaviours and attitudes in Great Britain. DESIGN AND SETTING: Independent online cross-sectional survey. PATIENTS AND INTERVENTIONS: Survey of 2221 individuals from a representative panel. MAIN OUTCOME MEASURES AND RESULTS: Excessive alcohol consumption is a widespread problem across Great Britain. Binge-drinking is common among 18-24 year olds, with 19% reporting drinking 10+ drinks on the same drinking day. 'Pre-loading' with alcohol at home before going out was reported by 30% of 18-24-year-old drinkers, of whom 36% get drunk twice or more a month, with 27% having injured themselves while drunk. Among older drinkers, 25% regularly drink to excess, 8% drink seven or more drinks on a typical drinking day and 9% self-reported drink-driving. Male gender was an independent risk factor for heavy (>40 units/week) alcohol abuse (odds ratio 3.05 (95% CI 1.82 to 5.10)). Men (19%) were more likely than women (8%, p<0.001) to report binge-drinking, drink-driving (11% vs 3%, p<0.001), or to have missed work owing to alcohol consumption (12% vs 7%, p<0.001). Young drinkers said they were heavily influenced by overall alcohol price and drink promotions. Increasing average weekly alcohol consumption, age <55 years, male gender, never having been married and being in full-time employment were all independently associated with a history of alcohol-related self-harm. Alcohol abuse was not related to socioeconomic status. CONCLUSIONS: Alcohol abuse remains common across all socioeconomic strata and geographical areas of Great Britain. Minimum pricing strategies and interventions that target cheap on-trade alcohol products seem likely to bring major public health benefits.

Mass spectrometry and informatics: distribution of molecules in the PubChem database and general requirements for mass accuracy in surface analysis.

Mass spectrometry is a powerful tool for the analysis and identification of substances across a broad range of technologies from proteomics and metabolomics through to surface analysis methods used for nanotechnology. A major challenge has been the development of automated methods to identify substances from the mass spectra. Public chemical databases have grown over 2 orders of magnitude in size over the past few years and have become a powerful tool in informatics approaches for identification. We analyze the popular PubChem database in terms of the population of substances with mass when resolved with typical mass spectrometer mass accuracies. We also characterize the average molecule in terms of the mass excess from nominal mass and the modal mass. It is shown, in agreement with other studies, that for the identification of unknowns a mass accuracy of around 1 ppm is required together with additional filtering using isotope patterns. This information is an essential part of a framework being developed for experimental library-free interpretation of complex molecule spectra in secondary ion mass spectrometry.

The effect of electrospray solvent composition on desorption electrospray ionisation (DESI) efficiency and spatial resolution.

In desorption electrospray ionisation (DESI) the interaction between the electrospray and the surface is key to two important analytical parameters, the spatial resolution and the sensitivity. We evaluate the effect of the electrospray solvent type, organic solvent fraction with water, analyte solubility and substrate wettability on DESI erosion diameter and material transferral into useful ion signal. To do this five amino acids, glycine, alanine, valine, leucine and phenylalanine are prepared as thin films on three substrates, UV/ozone treated glass, glass and polytetrafluoroethylene (PTFE). Four different solvents, acetonitrile (ACN), methanol (MeOH), ethanol (EtOH) and propan-2-ol (IPA), are used with organic solvent fractions with water varying from 0.1 to 1. These model systems allow the solubility or wettability to be kept constant as other parameters are varied. Additionally, comparison with electrospray ionisation (ESI) allows effects of ionisation efficiency to be determined. It is shown that the DESI efficiency is linearly dependent on the solubility (for these materials at least) and for analytes with solubilities below 1.5 g kg(-1), additional strategies may be required for DESI to be effective. We show that the DESI erosion diameter improves linearly with organic solvent fraction, with an organic solvent fraction of 0.9 instead of 0.5 leading to a 2 fold improvement. Furthermore, this leads to a 35 fold increase in DESI efficiency, defined as the molecular ion yield per unit area. It is shown that these improvements correlate with smaller droplet sizes rather than surface wetting or ionisation.

Organic depth profiling of a nanostructured delta layer reference material using large argon cluster ions.

Cluster ion beams have revolutionized the analysis of organic surfaces in time-of-flight secondary ion mass spectrometry and opened up new capabilities for organic depth profiling. Much effort has been devoted to understanding the capabilities and improving the performance of SF(5)(+) and C(60)(n+), which are successful for many, but not all, organic materials. Here, we explore the potential of organic depth profiling using novel argon cluster ions, Ar(500)(+) to Ar(1000)(+). We present results for an organic delta layer reference sample, consisting of ultrathin "delta" layers of Irganox 3114 (approximately 2.4 nm) embedded between thick layers of Irganox 1010 (approximately 46 or 91 nm). This indicates that, for the reference material, major benefits can be obtained with Ar cluster ions, including a constant high sputtering yield throughout a depth of approximately 390 nm, and an extremely low sputter-induced roughness of <5 nm. Although the depth resolution is currently limited by an instrumental artifact, and may not be the best attainable, these initial results strongly indicate the potential to achieve high depth resolution and suggest that Ar cluster ions may have a major role to play in the depth profiling of organic materials.

Developing repeatable measurements for reliable analysis of molecules at surfaces using desorption electrospray ionization.

Desorption electrospray ionization (DESI) is a powerful ambient ionization technique that can provide high-sensitivity mass spectrometry information directly from surfaces at ambient pressure. Although a growing amount of research has been devoted to exploring different applications, there are few studies investigating the basic parameters and underpinning metrology. An understanding of these is crucial to develop DESI as the robust and reliable technique required for significant uptake by industry. In this work, we begin with a systematic study of the parameters affecting the repeatability, sensitivity, and rate of consumption of material with DESI. To do this we have developed a model sample consisting of a thin uniform film of controlled thickness of Rhodamine B on glass. This model sample allowed assessment of optimal sensitivity and spot shape under different conditions. In addition, it allowed us to study the surface in more detail to understand why and how each parameter affects these. Using the model sample to optimize the instrument parameters for DESI led to an absolute intensity repeatability of better than 15%, achieved over a period of 1 day. This model sample provides valuable insight into the electrospray-sample interaction and the desorption mechanism. Confocal microscopy of areas analyzed by DESI allow droplet distribution, material utilization, and spot size to be determined. Studying surface erosion also gives the erosion rate of material, analogous to the sputtering yield in secondary ion mass spectrometry. The results of the study provide a clear description that explains the differences observed with changing electrospray parameters allowing optimization of the technique, for both spatial resolution and sensitivity.

Analysis of the interface and its position in C60(n+) secondary ion mass spectrometry depth profiling.

C60(n+) ions have been shown to be extremely successful for SIMS depth profiling of a wide range of organic materials, causing significantly less degradation of the molecular information than more traditional primary ions. This work focuses on examining the definition of the interface in a C60(n+) SIMS depth profile for an organic overlayer on a wafer substrate. First it investigates the optimum method to define the organic/inorganic interface position. Variations of up to 8 nm in the interface position can arise from different definitions of the interface position in the samples investigated here. Second, it looks into the reasons behind large interfacial widths, i.e., poor depth resolution, seen in C60(n+) depth profiling. This work confirms that, for Irganox 1010 deposited on a wafer, the depth resolution at the Irganox 1010/substrate interface is directly correlated to the roughening of material. C60n+