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ObjectiveStudies in countries where assisted dying is legal show that bereaved people express concern over the potential for social disapproval and social stigma because of the manner of death. There are indications that voluntary assisted dying is judged as less acceptable if the deceased is younger. A vignette-based experiment was used to determine whether public stigma (i.e., negative emotional reactions and desired social distance) and expected grief symptoms are higher for conjugally bereaved people through voluntary assisted dying (vs. long-term illness), when the deceased is a young adult (vs. older adult).MethodA 2 × 2 randomized factorial design was conducted with 164 Australian adults (130 women, 34 men, Mage = 37.69 years). Each participant was randomized online to read one of four vignettes and completed measures of anger, fear, prosocial emotions, desire for social distance, and expectations of grief symptomatology.ResultsA multivariate analysis of variance (MANOVA) was conducted. Death at a young age (28 years) was significantly associated with stronger negative emotional reactions of fear ($\eta _p^2 = 0.04$, P = 0.048) and anger ($\eta _p^2 = 0.06$, P = 0.010). There were no differences in outcomes associated with the mode of death, nor was there an interaction between mode of death and age group.Significance of resultsConcerns that voluntary assisted dying elicits public stigma appear unfounded. The fact that participants reported significantly higher anger and fear in response to bereaved people experiencing loss at a younger (vs. older) age, irrespective of cause of death, indicates that young people who lose their spouse might benefit from additional support.

Background: Repetitive negative thinking is conceptualized to be a transdiagnostic process linked to the development and maintenance of psychopathology. Prior research distinguishes between disorder-specific exemplars (worry, rumination) and transdiagnostic measures of repetitive negative thinking with differences across disorders reported. However, establishing the measurement invariance of these measures is necessary to support meaningful comparisons across clinical groups. Method: Bayesian structural equation modelling was used to assess the approximate invariance of the Ruminative Response Scale, Penn State Worry Questionnaire, and the Repetitive Thinking Questionnaire across individuals with a principal diagnosis of either depressive disorder, social anxiety disorder, or generalized anxiety disorder. Results: All scales demonstrated approximate measurement invariance across the three disorder groups. The depressive disorder group reported a higher level of rumination than the generalized anxiety disorder group (Δµ = 0.25, 95% Credibility Interval [0.06, 0.45]), with no difference between the generalized anxiety disorder and social anxiety disorder groups. The depressive disorder and generalized anxiety disorder groups did not differ in their levels of trait repetitive negative thinking, but the social anxiety disorder group was markedly lower than the generalized anxiety disorder group (Δµ = −0.21 [−0.37, −0.05]). Similarly, levels of worry did not differ between the generalized anxiety disorder and depressive disorder group but were lower in the social anxiety disorder group than the generalized anxiety disorder group (Δµ = −0.23 [−0.41, −0.06]). Conclusions: The Ruminative Response Scale, Penn State Worry Questionnaire, and Repetitive Thinking Questionnaire are measuring trait repetitive negative thinking in a consistent manner across individuals with a principal diagnosis of depressive disorder, social anxiety disorder, or generalized anxiety disorder. This supports their use in transdiagnostic contexts and indicates that it is appropriate to directly compare the scores on these measures between diagnostic groups.

Background: Interviews are a common method of data collection in palliative care research because they facilitate the gathering of rich, experiential data that are important for theory and practice. What is less clear is the extent to which those interviewed are representative of the larger group. Objective: The aim of this study was to determine if family caregivers who volunteer to be interviewed were similar or different to those who do not. Design: This study used data from the Caregiving and Bereavement study, a prospective, longitudinal mixed-methods study of family caregivers' general health, quality of life, and grief. Setting/Subjects: The 16 caregivers who volunteered to be interviewed were compared to the 20 who did not. Measurements: Comparisons were made in terms of the caregivers' demographic characteristics as well as measures of their quality of life, general health, general grief, and caregiver prolonged grief (i.e., before death). Results: Compared to caregivers who did not volunteer for an interview, those who volunteered were significantly older and reported less caregiver prolonged grief. Logistic regression showed that for each 1-unit increase in the caregiver prolonged grief score, individuals were 13% less likely to agree to an interview. Conclusions: Research findings based upon family caregivers who volunteer for research interviews might not provide a full picture of their experiences and needs. Researchers are encouraged to consider strategies that sample broadly and promote the participation of the full range of family caregivers in research to address the neglected areas of pre- and postdeath bereavement care.

The criminal offense of stalking is somewhat different to other offenses due to the repetitive, innocuous, and often multifaceted nature of the crime. Given that stalking constitutes a number of different behaviors, such as violence and threats, research on stalking recidivism becomes difficult as recidivism can be defined in a number of ways. This study utilized a dataset of Western Australia Police Force incident reports, comprising a sample of 404 stalking offenders. Survival curves and a binomial logistic regression were used to determine time to recidivism and predictors of recidivism, using four different definitions of recidivism. Predictor variables included age of the offender, prior history of criminal charges, and offender ethnicity. The four definitions ranged from narrow (a new stalking charge) to broad (any new criminal charge). The results of the study show that stalkers reoffend quickly, however our understanding of how fast and which offender characteristics predict recidivism, is dependent on how we define recidivism. This highlights the importance of considering how stalking recidivism is defined in future works and may explain current differences in stalking recidivism findings.

BACKGROUND The Bivalent Fear of Evaluation Model proposes that the fears of positive and negative evaluation each uniquely contribute to social anxiety severity. However, the debate continues as to whether these are distinct constructs, and, if so, the degree of influence each has on social anxiety severity. This study used a longitudinal evaluation of these relationships in a clinical sample to identify whether the two fears differentially change over time and differentially relate to social anxiety severity. METHODS Individuals with a social anxiety disorder (N = 105) completed measures of fears of negative and positive evaluation weekly, and social interaction anxiety monthly, for 12 weeks. Temporal relationships were assessed using residual dynamic structural equation modeling. RESULTS Fears of positive and negative evaluation both predicted the future status of the other (ϕ = 0.18, 95% credibility interval [0.10-0.28] and ϕ = 0.22 [0.12-0.35], respectively). Fear of negative evaluation (ϕ = 0.16 [0.05-0.28]) but not positive evaluation (ϕ

BackgroundCognitive behavior therapy (CBT) is effective for most patients with a social anxiety disorder (SAD) but a substantial proportion fails to remit. Experimental and clinical research suggests that enhancing CBT using imagery-based techniques could improve outcomes. It was hypothesized that imagery-enhanced CBT (IE-CBT) would be superior to verbally-based CBT (VB-CBT) on pre-registered outcomes.MethodsA randomized controlled trial of IE-CBT v. VB-CBT for social anxiety was completed in a community mental health clinic setting. Participants were randomized to IE (n = 53) or VB (n = 54) CBT, with 1-month (primary end point) and 6-month follow-up assessments. Participants completed 12, 2-hour, weekly sessions of IE-CBT or VB-CBT plus 1-month follow-up.ResultsIntention to treat analyses showed very large within-treatment effect sizes on the social interaction anxiety at all time points (ds = 2.09–2.62), with no between-treatment differences on this outcome or clinician-rated severity [1-month OR = 1.45 (0.45, 4.62), p = 0.53; 6-month OR = 1.31 (0.42, 4.08), p = 0.65], SAD remission (1-month: IE = 61.04%, VB = 55.09%, p = 0.59); 6-month: IE = 58.73%, VB = 61.89%, p = 0.77), or secondary outcomes. Three adverse events were noted (substance abuse, n = 1 in IE-CBT; temporary increase in suicide risk, n = 1 in each condition, with one being withdrawn at 1-month follow-up).ConclusionsGroup IE-CBT and VB-CBT were safe and there were no significant differences in outcomes. Both treatments were associated with very large within-group effect sizes and the majority of patients remitted following treatment.

Ion mobility spectrometry was utilized to corroborate the identity of streptorubin B (2) as the natural product produced by Streptomyces coelicolor. Natural product 2 was initially assigned as butylcycloheptylprodigiosin (3), and only relatively recently was this assignment clarified. We present additional evidence of this assignment by comparing collisional cross sections (Ω) of synthetic standards of 2, 3, and metacycloprodigiosin (4) to the cyclic prodiginine produced by S. coelicolor. Calculated theoretical Ω values demonstrate that cyclic prodiginines could be identified without standards. This work highlights ion mobility as an efficient tool for the dereplication of natural products.

The 14- and 16-membered macrolide antibiotics are an important structural class. Ubiquitously produced by a number of bacterial strains, namely actinomycetes, purification and structure elucidation of the wide array of analogs is challenging, both for discovery efforts and methodologies to monitor for byproducts, metabolites, and contaminants. Collision-induced dissociation mass spectrometry offers an attractive solution, enabling characterization of mixtures, and providing a wealth of structural information. However, interpretation of these spectra can be difficult. We present a study of 14- and 16-membered macrolide antibiotics, including MSn analysis for unprecedented depth of coverage, and complimentary analysis with D2O and H218O labeling to elucidate fragmentation mechanisms. These analyses contrast the behaviors of varying classes of macrolides and highlight how analogues can be identified in relation to similar structures, which will provide utility for future studies of novel macrolides, as well as impurities, metabolites, and degradation products of pharmaceuticals. Graphical Abstract.

The Ways of Coping Questionnaire (WCQ) is used extensively in health research, but the measurement properties and suitability of the WCQ for people with Parkinson’s disease (PD) have not been psychometrically assessed. If the WCQ does not align with its original 8-factor structure in a PD population, the use of the WCQ subscales may not be appropriate. The present study used confirmatory factor analysis (CFA), exploratory factor analysis (EFA), and multiple-group EFA to determine the ideal factor structure of the WCQ in a PD sample. The original 8 factors of the WCQ were not reproduced. EFA revealed a 6-factor structure, including Distancing, Faith, Avoidance, Seeking Social Support, Planful Problem Solving, and Confrontive coping. As motor symptom severity may impact coping, the stability of the 6-factor structure was examined across motor symptom severity (mild and moderate), remaining consistent. Higher levels of overall motor severity were associated with increased use of faith and avoidance style coping. These findings suggest that the 6-factor structure of the WCQ may be more appropriate for assessing coping styles in PD.

Social anxiety disorder (SAD) is associated with marked physiological reactivity in social-evaluative situations. However, objective measurement of biomarkers is rarely evaluated in treatment trials, despite potential utility in clarifying disorder-specific physiological correlates. This randomized controlled trial sought to examine the differential impact of imagery-enhanced vs. verbal-based cognitive behavioral group therapy (IE-CBGT, n = 53; VB-CBGT, n = 54) on biomarkers of emotion regulation and arousal during social stress in people with SAD (pre- and post-treatment differences in heart rate variability (HRV) and skin conductance). We acquired psychophysiological data from randomized participants across four social stress test phases (baseline, speech preparation, speech, interaction) at pre-treatment, and 1- and 6-months post-treatment. Analyses revealed that IE-CBGT selectively attenuated heart rate as indexed by increases in median heart rate interval (median-RR) compared to VB-CBGT at post-treatment, whereas one HRV index showed a larger increase in the VB-CBGT condition before but not after controlling for median-RR. Other psychophysiological indices did not differ between conditions. Lower sympathetic arousal in the IE-CBGT condition may have obviated the need for parasympathetic downregulation, whereas the opposite was true for VB-CBGT. These findings provide preliminary insights into the impact of imagery-enhanced and verbally-based psychotherapy for SAD on emotion regulation biomarkers.

Cognitive behavior therapy (CBT) is effective for most patients with a social anxiety disorder (SAD) but a substantial proportion fails to remit. Experimental and clinical research suggests that enhancing CBT using imagery-based techniques could improve outcomes. It was hypothesized that imagery-enhanced CBT (IE-CBT) would be superior to verbally-based CBT (VB-CBT) on pre-registered outcomes.A randomized controlled trial of IE-CBT v. VB-CBT for social anxiety was completed in a community mental health clinic setting. Participants were randomized to IE (n = 53) or VB (n = 54) CBT, with 1-month (primary end point) and 6-month follow-up assessments. Participants completed 12, 2-hour, weekly sessions of IE-CBT or VB-CBT plus 1-month follow-up.Intention to treat analyses showed very large within-treatment effect sizes on the social interaction anxiety at all time points (ds = 2.09-2.62), with no between-treatment differences on this outcome or clinician-rated severity [1-month OR = 1.45 (0.45, 4.62), p = 0.53; 6-month OR = 1.31 (0.42, 4.08), p = 0.65], SAD remission (1-month: IE = 61.04%, VB = 55.09%, p = 0.59); 6-month: IE = 58.73%, VB = 61.89%, p = 0.77), or secondary outcomes. Three adverse events were noted (substance abuse, n = 1 in IE-CBT; temporary increase in suicide risk, n = 1 in each condition, with one being withdrawn at 1-month follow-up).Group IE-CBT and VB-CBT were safe and there were no significant differences in outcomes. Both treatments were associated with very large within-group effect sizes and the majority of patients remitted following treatment.

The COVID-19 pandemic has had a severe impact on mental health worldwide, with increased rates of anxiety and depression widely documented. The aim of this study was to examine unguided low intensity cognitive behaviour therapy for anxiety and depression during the pandemic. A sample of 225 individuals in Australia and the United Kingdom (M age 37.79, SD = 14.02, range 18-80 years; 85% female) were randomised into intervention or waitlist control. The intervention group demonstrated significant decreases in anxiety (d = 0.36 [0.18, 0.54]) and depression (d = 0.28 [0.11, 0.45]) compared to controls. The majority of participants (96%) rated the intervention as useful, and most (83%) reported they spent 30 min or less reading the guide, with 83% agreeing the intervention was easy to read. The results indicate that low intensity cognitive behaviour therapy has efficacy in reducing anxiety and depression during the COVID-19 pandemic. There is an urgent need to disseminate low intensity psychological therapies to improve mental health in this challenging time.

Background: Determining the effect of caregiving and bereavement remains a challenge. To date, no study has employed a comparison group to investigate caregivers’ grief, quality of life and general health in relation to non-caregivers. Aim: We aimed to determine how caregivers’ grief, quality of life and general health changed following death compared to non-caregivers and whether pre-death grief predicted these outcomes. Design: A prospective, longitudinal study of family caregivers and a comparison group matched for age, gender and postcode was conducted. All participants completed questionnaires at four points – once pre-death and three times post-death (3–4 months, 6–7 months and 9–10 months). Setting/participants: Participants ( N = 70) were family caregivers of persons receiving palliative care, mostly for cancer, recruited from three palliative care providers in Western Australia and matched comparisons recruited from advertisements. Results: There were significant differences between the caregivers’ and comparisons’ grief, general health and quality of life at pre-death, 3–4 months and 6–7 months post-death, but not at 9–10 months post-death. The rate of progression in these constructs following death was independent from the intensity of pre-death grief. However, caregiver prolonged grief score significantly predicted prolonged grief score at 6–7 and 9–10 months post-death. Conclusion: It took 9–10 months for the caregivers’ grief, general health and quality of life to correspond to the comparison group. These findings present an opportunity for palliative care research and practice to consider how best to support the majority of caregivers without grief complications so that their pre- and post-death support needs are realised.

Lsr2 is a nucleoid-associated protein conserved throughout the actinobacteria, including the antibiotic-producingStreptomyces.Streptomycesspecies encode paralogous Lsr2 proteins (Lsr2 and Lsr2-like, or LsrL), and we show here that of the two, Lsr2 has greater functional significance. We found that Lsr2 binds AT-rich sequences throughout the chromosome, and broadly represses gene expression. Strikingly, specialized metabolic clusters were over-represented amongst its targets, and the cryptic nature of many of these clusters appears to stem from Lsr2-mediated repression. Manipulating Lsr2 activity in model species and uncharacterized isolates resulted in the production of new metabolites not seen in wild type strains. Our results suggest that the transcriptional silencing of biosynthetic clusters by Lsr2 may protectStreptomycesfrom the inappropriate expression of specialized metabolites, and provide global control overStreptomyces’arsenal of signalling and antagonistic compounds.

Lsr2 is a nucleoid-associated protein conserved throughout the actinobacteria, including the antibiotic-producing Streptomyces. Streptomyces species encode paralogous Lsr2 proteins (Lsr2 and Lsr2-like, or LsrL), and we show here that of the two, Lsr2 has greater functional significance. We found that Lsr2 binds AT-rich sequences throughout the chromosome, and broadly represses gene expression. Strikingly, specialized metabolic clusters were over-represented amongst its targets, and the cryptic nature of many of these clusters appears to stem from Lsr2-mediated repression. Manipulating Lsr2 activity in model species and uncharacterized isolates resulted in the production of new metabolites not seen in wild type strains. Our results suggest that the transcriptional silencing of biosynthetic clusters by Lsr2 may protect Streptomyces from the inappropriate expression of specialized metabolites, and provide global control over Streptomyces’ arsenal of signaling and antagonistic compounds.

The 14- and 16-membered macrolide antibiotics are an important structural class. Ubiquitously produced by a number of bacterial strains, namely actinomycetes, purification and structure elucidation of the wide array of analogs is challenging, both for discovery efforts and methodologies to monitor for byproducts, metabolites, and contaminants. Collision-induced dissociation mass spectrometry offers an attractive solution, enabling characterization of mixtures, and providing a wealth of structural information. However, interpretation of these spectra can be difficult. We present a study of 14- and 16-membered macrolide antibiotics, including MS

Background The Depression, Anxiety, and Stress Scale -21 (DASS-21) is a frequently used measure of emotional disturbance symptoms in Parkinson's disease (PD). However, the factor structure of the DASS-21 in PD has yet to be explored. Objective To assess whether the scale is measuring these symptoms in PD in the same way as the general population. Methods The present study fit a series of established DASS-21 factor structures with both confirmatory factor analysis (CFA) and exploratory structural equation modelling (ESEM) using data from 251 participants with PD. Results The 3-factor ESEM provided the best fit. The depression and stress scales fit well, however, few items on the anxiety subscale loaded clearly, with several items significantly loading onto the depression or stress factors. Conclusions Whilst the depression and stress subscales appear suitable in PD, poor loadings and internal consistency indicate the anxiety subscale may not accurately assess anxiety symptomology in PD. This may be due to the scale's reliance on physiological symptoms as indicators of anxiety, when many of these are present in PD. Thus, the anxiety subscale of the DASS-21 may not be a suitable measure of anxiety in PD.

International audience; The potential of the diverse chemistries present in natural products (NP) for biotechnology and medicine remains untapped because NP databases are not searchable with raw data and the NP community has no way to share data other than in published papers. Although mass spectrometry (MS) techniques are well-suited to high-throughput characterization of NP, there is a pressing need for an infrastructure to enable sharing and curation of data. We present Global Natural Products Social Molecular Networking (GNPS; http://gnps.ucsd.edu), an open-access knowledge base for community-wide organization and sharing of raw, processed or identified tandem mass (MS/MS) spectrometry data. In GNPS, crowdsourced curation of freely available community-wide reference MS libraries will underpin improved annotations. Data-driven social-networking should facilitate identification of spectra and foster collaborations. We also introduce the concept of 'living data' through continuous reanalysis of deposited data.

This study examined whether standard cognitive training, tailored cognitive training, transcranial direct current stimulation (tDCS), standard cognitive training + tDCS, or tailored cognitive training + tDCS improved cognitive function and functional outcomes in participants with PD and mild cognitive impairment (PD-MCI). Forty-two participants with PD-MCI were randomized to one of six groups: (1) standard cognitive training, (2) tailored cognitive training, (3) tDCS, (4) standard cognitive training + tDCS, (5) tailored cognitive training + tDCS, or (6) a control group. Interventions lasted 4 weeks, with cognitive and functional outcomes measured at baseline, post-intervention, and follow-up. The trial was registered with the Australian New Zealand Clinical Trials Registry (ANZCTR:12614001039673). While controlling for moderator variables, Generalized Linear Mixed Models (GLMMs) showed that when compared to the control group, the intervention groups demonstrated variable statistically significant improvements across executive function, attention/working memory, memory, language, activities of daily living (ADL), and quality of life (QOL; Hedge’sgrange = 0.01 to 1.75). More outcomes improved for the groups that received standard or tailored cognitive training combined with tDCS. Participants with PD-MCI receiving cognitive training (standard or tailored) or tDCS demonstrated significant improvements on cognitive and functional outcomes, and combining these interventions provided greater therapeutic effects.

Mass spectrometry is a powerful tool in natural product structure elucidation, but our ability to directly correlate fragmentation spectra to these structures lags far behind similar efforts in peptide sequencing and proteomics. Often, manual data interpretation is required and our knowledge of the expected fragmentation patterns for many scaffolds is limited, further complicating analysis. Here, we summarize advances in natural product structure elucidation based upon the application of collision induced dissociation fragmentation mechanisms.

BackgroundAlthough a meta-analysis has confirmed the association between antidepressant exposure in utero and subsequent poor neonatal adaptation, few identified studies included drug levels or standardized measures and only two studies followed up children who developed symptoms beyond infancy.MethodsThe study draws on the Mercy Pregnancy and Emotional Wellbeing Study and reports on 42 women/infant pairs at delivery. In all, 31 women continued to take antidepressants until delivery and 11 ceased earlier in pregnancy. Poor neonatal adaptation was assessed twice daily for up to 6 days by using the Neonatal Abstinence Scoring System (NASS). Drug levels were analyzed in umbilical cord blood and maternal blood obtained at delivery.ResultsIn total, 76% (32 of 42) of neonates exposed to antidepressants had symptoms observed on the NASS. These symptoms occurred up to 5 days postpartum with 25% having symptoms that persisted for more than 3 days. The most frequent symptoms were correlated most closely to antidepressant drug levels. Elevated NASS scores were found to be associated with poorer fine motor development at 6 months of age.ConclusionsPoor neonatal adaptation may be more common than previously recognized. The NASS was observed to be an effective assessment and monitoring measure. Research following symptomatic infants beyond the neonatal period is required.

Maternal mental health represents a significant global health burden. The Mercy Pregnancy and Emotional Well-being Study (MPEWS) was established to provide a comprehensive investigation of early developmental mechanisms and modifiers for maternal, fetal and child emotional well-being. MPEWS is a prospective, longitudinal study from pregnancy to 36 months postpartum that includes diagnostic measures of maternal mental health, observational measures of the mother-infant relationship, measures of child development, and repeat biological sampling. A total of 282 pregnant women were recruited in early pregnancy from the Mercy Hospital for Women in Melbourne, Australia, including 52 women on antidepressant medication, 31 non-medicated women meeting diagnostic criteria for current unipolar depression or dysthymia, and 65 women with a past history of depression. Sample recruitment characteristics included a mean age of 31 years and average gestation of 16 weeks. The MPEWS cohort was comparable to national averages for Australia on key pregnancy and birth variables. Those participants taking antidepressant medication had higher mean Edinburgh Postnatal Depression Scale (EPDS) and State Trait Anxiety Inventory (STAI) scores than the cohort as a whole but were comparable on other key variables. The MPEWS protocol provides a unique opportunity to evaluate the impact of pregnancy mental health on future maternal mental health and child development to aid the development of evidence-based interventions. The study is open for collaborative proposals via approach to the principal investigators.

The present study examined the relationship between executive function (EF) and fine motor control in young and older healthy adults. Participants completed 3 measures of executive function; a spatial working memory (SWM) task, the Stockings of Cambridge task (planning), and the Intra-Dimensional Extra-Dimensional Set-Shift task (set-shifting). Fine motor control was assessed using 3 subtests of the Purdue Pegboard (unimanual, bimanual, sequencing). For the younger adults, there were no significant correlations between measures of EF and fine motor control. For the older adults, all EFs significantly correlated with all measures of fine motor control. Three separate regressions examined whether planning, SWM and set-shifting independently predicted unimanual, bimanual, and sequencing scores for the older adults. Planning was the primary predictor of performance on all three Purdue subtests. A multiple-groups mediation model examined whether planning predicted fine motor control scores independent of participants' age, suggesting that preservation of planning ability may support fine motor control in older adults. Planning remained a significant predictor of unimanual performance in the older age group, but not bimanual or sequencing performance. The findings are discussed in terms of compensation theory, whereby planning is a key compensatory resource for fine motor control in older adults.

Parkinson’s disease is a progressive neurodegenerative disorder associated with reduced spatial and verbal working memory ability. There are two established motor subtypes of PD, tremor dominant (TD) and postural instability and gait difficulty (PIGD). This study used structural equation modelling to explore the longitudinal relationship between the two subtypes and working memory assessed at a 2-year follow-up. The study comprised 84 males and 30 females (N = 114), aged between 39 and 85 (M = 64.82, SD = 9.23) with confirmed PD. There was no significant relationship between motor subtype at Time 1 and working memory at Time 2. Postural symptom severity at Time 1 predicted Time 2 spatial working memory for the PIGD subtype (p = .011) but not the TD subtype. Tremor symptoms were not associated with Time 2 working memory in either subtype. Predictive significance of Time 1 postural symptoms only in the PIGD subtype suggests an interaction between symptom dominance (subtype) and symptom severity that future subtyping should consider. This study demonstrates a predictive relationship between postural difficulties and working memory performance assessed at a 2-year follow-up. Establishing physical symptoms as predictors of cognitive change could have significant clinical importance.

We have compared over 500 RPLC columns characterized by the hydrophobic subtraction model using the system selectivity cube (SSC). We have shown numerous differences in column selectivity even among columns in the same class (e.g., alkyl-silica, cyano, or embedded polar groups). We also illustrate the utility of our method for selecting alternative columns with different selectivities for problematic separations and for selecting orthogonal columns for use in two-dimensional separations. The system selectivity cube offers a visual way to easily compare many columns simultaneously and select those columns offering the desired selectivity.

Mass spectrometry is a powerful tool in natural product structure elucidation, but our ability to directly correlate fragmentation spectra to these structures lags far behind similar efforts in pep...

A method for real-time, in situ measurement of oxygen transport across oil-in-water emulsion interface was developed. This method is based on reversible fluorescence quenching of tris ruthenium (II) bis (hexafluorophosphate) complex dye encapsulated in the oil phase of an emulsion upon interaction with oxygen. Oxygen transport across the oil–water interface for four different emulsions (whey protein isolate (WPI), sodium-dodecyl sulphate (SDS), cross-linked WPI and SDS–chitosan emulsions) was measured and effective diffusion coefficients were calculated. Results show that cross-linking of WPI did not alter the oxygen transport rate (p > 0.01), while addition of a chitosan layer to the SDS emulsion significantly reduced the oxygen transport rate (p

2010 marked the 50th anniversary of the use of selectivity triangles to characterize chromatographic phases. Such plots ultimately identify and quantify the blend of intermolecular interactions that occur between solutes and solvents/phases. The first chromatographic triangle was proposed by Brown and applied to GC stationary phases. Snyder then developed the influential solvent selectivity triangle (SST) based on the gas-liquid partition data of Rohrschneider. The SST was combined with simplex experimental designs to optimize RPLC separations. Subsequent criticisms of the work revolved around the inaccurate predictions that resulted from the SST. These inaccuracies ultimately relate to the inability of the SST to account for the effects of water on the interaction ability of organic solvents. Other criticisms focused on the selection of the three probe solutes (ethanol, dioxane, and nitromethane) that were used to define the apices of the SST. Here, the concerns include the lack of explicit consideration of dispersion interactions and the fact that the three probes do not represent any single intermolecular interaction but rather reflect a blend of intermolecular interactions. The SST approach was modified for NPLC by redefining the triangle apices to reflect the localization, general adsorption, and basicity of NPLC mobile phase modifiers. Because water is generally absent in NPLC, the triangle approach leads to better predictions for NPLC than for RPLC. In subsequent modifications of selectivity triangles, Fu and Khaledi have created a micellar selectivity triangle (MST) based on linear solvation energy relationships (LSERs) and Zhang and Carr have used the Dolan-Snyder hydrophobic subtraction model to create RPLC column selectivity triangles. We end this review by highlighting more recent methods for comparing selectivities and by discussing a new 3D visualization tool for classifying chromatographic systems as having similar or different fundamental energetics of retention and hence having similar or different selectivities.

The overall goal of this study was to develop a rapid method based on optical imaging and spectroscopy for real time characterization of interactions of free radicals with oil in water emulsions. The method was based on encapsulation of a lipid soluble, free radical sensitive dye that transforms from a non-fluorescent to a fluorescent state upon reaction with hydroxyl radicals. Using this approach, interaction of hydroxyl radicals generated using the Fenton's reagents in aqueous phase with free radical sensitive dye encapsulated in the oil phase of whey protein isolate (WPI) stabilized emulsion was characterized. The results based on fluorescence imaging and spectroscopy showed a linear increase in fluorescence of free radical sensitive dye during the initial time period (~ 30 min) of incubation with the Fenton's reagents. The results showed a high degree of correlation between spectroscopy and quantitative fluorescence imaging measurements. Increase in fluorescence of free radical sensitive dye was a function of concentration of ferrous ions and hydrogen peroxide. Incorporation of EDTA reduced the rate of increase in fluorescence of the dye due to the chelation of metal ions (p

Chromatography is a technique used to separate and quantify the components in a complex chemical mixture. We have created a 3D visualization system capable of comparing the chemical properties of chromatographic systems. The visualization system combines scatter plots, parallel coordinates, and specialized glyphs to assist in the analysis of chromatographic data and comparisons of multiple systems. Using this tool, numerous separation systems can be readily compared simultaneously - greatly facilitating the ability to select systems that are likely to produce desired separations during method development.

A three-dimensional visualization tool termed the system selectivity cube (SSC) has been developed to aid in the selection of chromatography systems. The most effective way to change the resolution of a complex mixture is to change the selectivity of the separation. The SSC allows efficient identification of systems of differing selectivity. Our approach is based on comparisons of the energetics of two systems and in this way is somewhat akin to the kappa-kappa plots of Horvath et al. Our comparisons, however, are based on linear solvation energy relationships (LSERs) or other multiparameter models of retention. Our approach unifies LSERs, kappa-kappa plots, and the "effective selectivity" concept introduced by Zhao and Carr. The utility and versatility of the SSC is demonstrated with LSERs for 74 micellar electrokinetic chromatography (MEKC) systems taken from the literature. The SSC groups those systems which provide little or no difference in selectivity and those systems which do differ in their selectivities. We anticipate that this approach will be useful for selecting replacement columns, systems that may offer better results for difficult separations, and orthogonal phases for 2D gas chromatography (GC) and reversed phase liquid chromatography (RPLC) separations.

The cavity ringdown absorption spectrum of 4-cyclopentene-1,3-dione was recorded near 487 nm in a room-temperature gas cell. The very weak band system (epsilon approximately 0.05 dm3 mol-1 cm-1) in this region is due to the T1(n,pi*)-- S0 electronic transition. The origin-band maximum was observed at 20540.0 +/- 0.5 cm-1. We have assigned about 40 vibronically resolved bands in a region extending to +1100 cm-1 relative to the origin. Assignments were aided by quantum-chemical calculations of the T1-- S0 0-0 excitation energy as well as ground-state vibrational frequencies. From the CRD spectral assignments, we determined fundamental frequencies for several vibrational modes in the T1 excited state, including the lowest-energy ring-bending and -twisting modes, nu19' (b1) and nu14' (a2), respectively. Their fundamentals in the T1 state are 160.5 and 246 cm-1, compared to 99 and 239 cm-1, respectively, in the S0 ground state. The increases in these ring frequencies upon electronic excitation signify that the nominal n --pi* chromophore is delocalized to include the conjugated ring atoms. The extent of this delocalization is different in the T1(n,pi*) vs S1(n,pi*) excited states. This conclusion is based on observed differences in T1 vs S1 ring fundamental frequencies.

A polyalanine-based peptide which forms a stable, negatively-charged α-helix in the gas phase is reported. Addition of an N-terminal acidic residue forms a stabilizing hydrogen bond network and an electrostatic interaction with the helical dipole. Formation of this secondary structure was demonstrated using ion mobility-mass spectrometry and molecular modelling techniques.

It is now well established that magneto-rheological (MR) fluids can provide the basis for constructing controllable vibration damping devices. Moreover, the characteristics of MR fluids are generally compatible with industrial requirements and there is enormous scope for commercial exploitation. In this paper the authors describe the design and construction of a vibration isolator which incorporates an MR damper. The damper is unusual in that it operates in the squeeze-flow mode. A quasi-steady model of the MR damper is summarised and then extended to include the vibration isolator dynamics. Model predictions are compared with experimental results. It is shown that by employing the MR damper a wide range of control can be exercised over the transmissibility of the vibration isolator. Also the quasi-steady model is able to account for observed behaviour.

The microorganisms on rock cod fillets stored in a modified atmosphere (MA; 80% CO 2 -20% air) at 4°C for 21 days were isolated. Only Lactobacillus sp. (71 to 87%) and tan-colored Pseudomonas sp.-like isolates (TAN isolates) were found. The TAN isolates grew more slowly in MA than in air at 8°C. When TAN isolates were grown in air at 8°C and then transferred to MA at 8°C, there was an initial decline in viable counts for 10 to 30 h followed by exponential growth. During this exponential growth phase in MA, the growth rates of the TAN isolates from MA-stored fish were significantly greater than those of the TAN isolates from fresh fish. When a TAN isolate from fresh fish was grown under MA for 21 days, it then grew as rapidly under MA as isolates from MA-stored fish. These results suggest that the TAN isolates genetically adapt to high levels of CO 2 .

The numbers and types of microorganisms on fresh rock cod fillets and fillets stored in air or in a modified atmosphere (MA; 80% CO 2 , 20% air) at 4°C were compared. Samples were analyzed after 0, 7, 14, and 21 days of storage. The isolation plates were incubated aerobically, anaerobically, or under MA at 4, 20, or 35°C. After 7 days of storage in air, the fillets were obviously spoiled and had a 3- to 4-log cycle increase in microbial counts. Plate counts increased more slowly on MA-stored fillets. After 21 days, the counts on the latter had increased only 2 log cycles, and the fillets did not seem spoiled. The microbial flora changed greatly during MA storage. Only Lactobacillus spp. (70%) and an Aeromonas sp.-like isolate (30%) were found on plates incubated aerobically at 4 and 20°C, and only Lactobacillus spp. was found on plates incubated aerobically and anaerobically at 35 and at 20°C under MA. Isolation plates incubated at 20°C in air gave the highest counts in the shortest incubation time and the greatest diversity of bacterial types recovered. No Vibrio parahaemolyticus, Staphylococcus aureus , or Clostridium botulinum type E were isolated from the fresh or MA-stored fillets.