Chaotic saddles and interior crises in a dissipative nontwist system.

We consider a dissipative version of the standard nontwist map. Nontwist systems present a robust transport barrier, called the shearless curve, that becomes the shearless attractor when dissipation is introduced. This attractor can be regular or chaotic depending on the control parameters. Chaotic attractors can undergo sudden and qualitative changes as a parameter is varied. These changes are called crises, and at an interior crisis the attractor suddenly expands. Chaotic saddles are nonattracting chaotic sets that play a fundamental role in the dynamics of nonlinear systems; they are responsible for chaotic transients, fractal basin boundaries, and chaotic scattering, and they mediate interior crises. In this work we discuss the creation of chaotic saddles in a dissipative nontwist system and the interior crises they generate. We show how the presence of two saddles increases the transient times and we analyze the phenomenon of crisis induced intermittency.

Analysis of rare disruptive germline mutations in 2135 enriched BRCA-negative breast cancers excludes additional high-impact susceptibility genes.

BACKGROUND: Breast cancer has a significant heritable basis, of which ∼60% remains unexplained. Testing for BRCA1/BRCA2 offers useful discrimination of breast cancer risk within families, and identification of additional breast cancer susceptibility genes could offer clinical utility. PATIENTS AND METHODS: We included 2135 invasive breast cancer cases recruited via the Breast and Ovarian Cancer Susceptibility study, a retrospective UK study of familial breast cancer. ELIGIBILITY CRITERIA: female, BRCA-negative, white European ethnicity, and one of: (i) breast cancer family history, (ii) bilateral disease, (iii) young age of onset (<30 years), and (iv) concomitant ovarian cancer. We undertook exome sequencing of cases and carried out gene-level burden testing of rare damaging variants against those from 51 377 ethnicity-matched population controls from gnomAD. RESULTS: 159/2135 (7.4%) cases had a qualifying variant in an established breast cancer susceptibility gene, with minimal evidence of signal in other cancer susceptibility genes. Known breast cancer susceptibility genes PALB2, CHEK2, and ATM were the only genes to retain statistical significance after correcting for multiple testing. Due to the enrichment of hereditary cases in the series, we had good power (>80%) to detect a gene of BRCA1-like risk [odds ratio (OR) = 10.6] down to a population minor allele frequency of 4.6 × 10-5 (1 in 10 799, less than one-tenth that of BRCA1)and of PALB2-like risk (OR = 5.0) down to a population minor allele frequency of 2.8 × 10-4 (1 in 1779, less than half that of PALB2). Power was lower for identification of novel moderate penetrance genes (OR = 2-3) like CHEK2 and ATM. CONCLUSIONS: This is the largest case-control whole-exome analysis of enriched breast cancer published to date. Whilst additional breast cancer susceptibility genes likely exist, those of high penetrance are likely to be of very low mutational frequency. Contention exists regarding the clinical utility of such genes.

Development and preliminary evaluation of the Neurofibromatosis Type 1 Adult Quality of Life (NF1-AdQoL) questionnaire.

BACKGROUND: Neurofibromatosis Type 1 (NF1) is a variable and unpredictable multisystem genetic disorder that predisposes to medical complications, cognitive impairment and disfigurement, of all which can impact negatively upon the health-related quality of life (HRQoL) of affected adults. AIMS: To develop and validate a disease-specific HRQoL adult questionnaire to evaluate effects of NF1 from the patient's viewpoint. METHODS: The Neurofibromatosis Type 1 Adult Health-related Quality of Life questionnaire (NF1-AdQoL) was based on patient interviews (n = 8), clinician survey and questionnaire pilot study. Adults with NF1 (n = 114, aged 18-40 years) were recruited from three Australian genetics clinics and completed the NF1-AdQoL, the 29-item Skindex (Skindex-29) and the 36-item Short Form, version 2 (SF-36v2) questionnaires. An exploratory factor analysis of the NF1-AdQoL was conducted to assess construct validity. Convergent and discriminant validity of the NF1-AdQoL was determined by using multitrait multimethod analysis with Skindex-29 and SF-36v2 scores. RESULTS: Factor analysis indicated that 62.7% of the common variance between the questionnaires could be explained by three factors: 'emotions associated with cosmetic appearance' (12 items), 'functioning - social and learning' (11 items) and 'physical symptoms' (8 items). NF1-AdQoL had good internal consistency (Cronbach α = 0.96). Convergent validity was confirmed by moderate associations with similarly named scales of the Skindex-29 and SF-36v2. Results from all three HRQoL questionnaires indicated overall healthy HRQoL for young to early middle-aged adults with NF1. CONCLUSION: The NF1-AdQoL is a relatively valid, feasible and fairly easy to read tool to measure the HRQoL of adults with NF1. Further evaluation is required to determine the test-retest reliability, responsiveness and validity of the NF1-AdQoL in larger adult NF1 cohorts.

Zonisamide safety in pregnancy: Data from the UK and Ireland epilepsy and pregnancy register.

BACKGROUND: Animal data suggest teratogenic effects with zonisamide use and risk of pregnancy losses. Human data following zonisamide exposure are presently limited, but suggest low risk of malformation with elevated risk of low birth weight. OBJECTIVE: To calculate the major congenital malformation (MCM) rate of zonisamide in human pregnancy and assess for a signal of any specific malformation pattern and associations with birth weight. METHODS AND MATERIALS: Data were obtained from the UK and Ireland Epilepsy and Pregnancy register (UKIEPR) which is an observational, registration, and follow up study from December 1996 to July 2020. Eligibility criteria were use of zonisamide and to have been referred to the UKIEPR before the outcome of the pregnancy was known. Primary outcome was evidence of MCM. RESULTS: From December 1996 through July 2020 there were 112 cases of first trimester exposure to zonisamide, including 26 monotherapy cases. There were 3 MCM for monotherapy cases (MCM rate 13.0% (95% confidence interval 4.5-32.1)), and 5 MCM for polytherapy cases (MCM rate 6.9% (95% confidence interval 3.0-15.2)). While the median birth weight was on 71st and 44th centile for monotherapy and polytherapy cases respectively, there was a high rate of infants born small for gestational age (21% for both). CONCLUSION: These data raise concerns about a signal for potential teratogenicity with zonisamide in human pregnancy. Given the low numbers reported, further data will be required to adequately counsel women who use zonisamide in pregnancy.

Oral dimethyl fumarate induces changes within the peripheral neutrophil compartment of patients with psoriasis that are linked with skin improvement.

BACKGROUND: Dimethyl fumarate (DMF) is a treatment for moderate-to-severe psoriasis and multiple sclerosis. DMF therapy typically improves skin inflammation within the first 3 months of treatment. DMF is a prodrug that generates the hydroxycarboxylic acid receptor 2 (HCA2) agonist, monomethyl fumarate (MMF). Despite widespread clinical use, DMF's mechanism of action is not fully understood. OBJECTIVES: We wished to characterize the changes induced by DMF in peripheral neutrophils within the first 3 months of treatment to better understand its early antipsoriatic effects. METHODS: Flow cytometry was used to assess T-cell and neutrophil frequencies, apoptosis and activation phenotype. In vitro culture of neutrophils with DMF and MMF was used to evaluate apoptosis and HCA2 internalization. Serum levels of neutrophil degranulation products were measured by enzyme-linked immunosorbent assay. RESULTS: Patients with psoriasis had significantly higher leucocyte counts at baseline compared with controls, with a large population of pro-inflammatory CD62Llo  CD11bbright neutrophils. Analysis revealed that DMF treatment reduced the frequency of CD62Llo  CD11bbright neutrophils and serum levels of neutrophil activation markers. This reduction was not linked to increased apoptosis. CONCLUSIONS: Our results reveal a novel in vivo effect of DMF therapy on pro-inflammatory neutrophils that likely contributes to this treatment's antipsoriatic efficacy.

Predictors of burden in Australian mental health caregivers: a cross-sectional survey.

BACKGROUND: The shift towards providing mental healthcare in the community has resulted in caregivers becoming more involved in the delivery of these services. Supporting mental health consumers can be burdensome which, in conjunction with the anguish that may result from observing their relative develop a mental illness, can lead to carers experiencing significant levels of distress. AIMS: This study aimed to quantify the extent to which specific aspects of caregiving contribute to mental health burden in Australia. METHODS: Participants were included if they were Australian mental health caregivers. An online questionnaire was distributed via email. Multivariate logistic regression was used to identify predictors of burden in mental health caregivers. RESULTS: Completed questionnaires were collected from 231 respondents. The logistic regression analysis yielded five factors that contributed significantly to mental health caregiver burden. Of these factors, a strained atmosphere and regularly carrying out tasks for consumers were the two strongest predictors of burden. CONCLUSION: Community health professionals could focus on interpersonal relationships between family members, access to disability and financial support services, and carers' views about the quality of healthcare provided to consumers. Addressing these issues may decrease carer burden and improve the quality of life for all family members.

Suicide risk and social support in Australian resource sector employees: A cross-sectional study.

This study examines the association between suicide risk and social support in Australian resource sector employees. We included 150 participants, who completed the Beck Hopelessness Scale and MOS-Social Support Survey. Data were analyzed using smallest space analysis and multidimensional scalogram analysis. The analysis identified four distinct regions, which were conceptualized as "confiding," "affection," "companionship," and "practical help." All of these components of social support were associated with hopelessness, which has important clinical implications as hopelessness is related to suicide risk. The results of this study also demonstrated that lower levels of social support, and greater sense of perceived hopelessness tended to lead to Australian resource workers seeking assistance from mental health professionals in the previous year. Attention should turn towards providing interventions that promote social support for employees in Australian resource industry.

Seasonal metabolic analysis of marine sediments collected from Moreton Bay in South East Queensland, Australia, using a multi-omics-based approach.

Anthropogenic effects of urban density have altered natural ecosystems. Such changes include eutrophication of freshwater and adjoining coastal habitats, and increased levels of inorganic nutrients and pollutants into waterways. In Australia, these changes are intensified by large-scale ocean-atmospheric events, leading to considerable abiotic stress on the natural flora and fauna. Bacterial communities in marine sediments from Moreton Bay (South East Queensland, Australia) were examined in order to assess the impact of rainfall changes, chemical pollution, and subsequent abiotic stress on living organisms within a marine ecosystem. Sediments were collected during the wet and dry seasons and analyzed using bacterial metagenomics and community metabolomics techniques. Physicochemical data were also analyzed to account for biological variance that may be due to non-rainfall-based abiotic stresses. Wet-dry seasonality was the dominant control on bacterial community structure and metabolic function. Changes in the availability of nutrients, organic matter and light appeared to be the major seasonal stressors. In contrast, urban and industrial pollutants appeared to be minor stressors at the sites sampled. During the wet season, the bacterial community composition reflected organisms that utilize biogeochemical pathways with fast kinetics, such as aerobic metabolism, direct assimilation of inorganic compounds, and primary production. The transition to the dry season saw the bacterial community composition shift towards organisms that utilize more complex organic energy sources, such as carbohydrates and fatty acids, and anaerobic redox processes.

The effect of self-selected complementary therapies on cancer patients' quality of life and symptom distress: A prospective cohort study in an integrative oncology setting.

OBJECTIVE: To examine the effectiveness of a multifaceted complementary therapies intervention, delivered in a systematic manner within an Australian public hospital setting, on quality of life and symptom distress outcomes for cancer patients. METHODS: Adults receiving treatment for any form of cancer were eligible to participate in this study. Self-referred participants were offered a course of six complementary therapy sessions. Measures were administered at baseline, and at the third and sixth visit. The primary outcomes were quality of life and symptom distress. Linear mixed models were used to assess change in the primary outcomes. RESULTS: In total, 1376 cancer patients participated in this study. The linear mixed models demonstrated that there were significant improvements in quality of life and significant reductions in symptom distress over six sessions. Body-based therapies demonstrated significantly superior improvement in quality of life over counselling, but no other differences between therapies were identified. Reduced symptom distress was not significantly associated with any particular type of therapy. CONCLUSION: A self-selected complementary therapies intervention, provided in an Australian public hospital by accredited therapists, for cancer patients significantly mproved quality of life and reduced symptom distress. The effect of this intervention on quality of life has particular salience, since cancer impacts on many areas of people's lives and impairs quality of life.

Mental Health Consumers' Motives for Seeking Advocacy Support: A Qualitative Exploration.

Advocacy plays a vital role in ensuring that mental health consumers' rights are maintained. However, the primary issues for which consumers seek advocacy support remain unknown. Understanding these issues provides a sound basis from which advocacy organisations may develop a clear service delivery focus. This study addresses the literature gap through presenting a qualitative analysis of 60 records from an advocacy service. Four major themes emerged, across which two key issues were dominant: the sense of fearfulness and disempowerment. These issues accentuate the importance of advocates in enhancing the agency of mental health consumers.

Epi-Two-Dimensional Fluid Flow: A New Topological Paradigm for Dimensionality.

While a variety of fundamental differences are known to separate two-dimensional (2D) and three-dimensional (3D) fluid flows, it is not well understood how they are related. Conventionally, dimensional reduction is justified by an a priori geometrical framework; i.e., 2D flows occur under some geometrical constraint such as shallowness. However, deeper inquiry into 3D flow often finds the presence of local 2D-like structures without such a constraint, where 2D-like behavior may be identified by the integrability of vortex lines or vanishing local helicity. Here we propose a new paradigm of flow structure by introducing an intermediate class, termed epi-two-dimensional flow, and thereby build a topological bridge between 2D and 3D flows. The epi-2D property is local and is preserved in fluid elements obeying ideal (inviscid and barotropic) mechanics; a local epi-2D flow may be regarded as a "particle" carrying a generalized enstrophy as its charge. A finite viscosity may cause "fusion" of two epi-2D particles, generating helicity from their charges giving rise to 3D flow.

Intraspecific variation and plasticity in mitochondrial oxygen binding affinity as a response to environmental temperature.

Mitochondrial function has been suggested to underlie constraints on whole-organism aerobic performance and associated hypoxia and thermal tolerance limits, but most studies have focused on measures of maximum mitochondrial capacity. Here we investigated whether variation in mitochondrial oxygen kinetics could contribute to local adaptation and plasticity in response to temperature using two subspecies of the Atlantic killifish (Fundulus heteroclitus) acclimated to a range of temperatures (5, 15, and 33 °C). The southern subspecies of F. heteroclitus, which has superior thermal and hypoxia tolerances compared to the northern subspecies, exhibited lower mitochondrial O2 P50 (higher O2 affinity). Acclimation to thermal extremes (5 or 33 °C) altered mitochondrial O2 P50 in both subspecies consistent with the effects of thermal acclimation on whole-organism thermal tolerance limits. We also examined differences between subspecies and thermal acclimation effects on whole-blood Hb O2-P50 to assess whether variation in oxygen delivery is involved in these responses. In contrast to the clear differences between subspecies in mitochondrial O2-P50 there were no differences in whole-blood Hb-O2 P50 between subspecies. Taken together these findings support a general role for mitochondrial oxygen kinetics in differentiating whole-organism aerobic performance and thus in influencing species responses to environmental change.

A multi-omics based ecological analysis of coastal marine sediments from Gladstone, in Australia's Central Queensland, and Heron Island, a nearby fringing platform reef.

The impact of anthropogenic factors arising from point and non-point pollution sources at a multi commodity marine port and its surrounding ecosystems were studied using sediment samples collected from a number of onshore (Gladstone Harbour and Facing Island) and offshore (Heron Island and Fitzroy Reefs) sites in Australia's Central Queensland. Sediment samples were analyzed for trace metals, organic carbon, polycyclic aromatic hydrocarbons (PAH), emerging chemicals of concern (ECC) and sterols. Similarly, the biological and biochemical interaction between the reef and its environment was analyzed by the multi-omic tools of next-generation sequencing characterization of the bacterial community and microbial community metabolic profiling. Overall, the trace elements were observed at the lower end of the Australian environmental guideline values at the offshore sites, while higher values were observed for the onshore locations Nickel and copper were observed above the high trigger value threshold at the onshore sites. The levels of PAH were below limits of detection across all sites. However, some of the ECC and sterols were observed at higher concentrations at both onshore and offshore locations, notably, the cholesterol family sterols and 17α-ethynylestradiol. Multi-omic analyses also indicated possible thermal and photo irradiation stressors on the bacterial communities at all the tested sites. The observed populations of γ-proteobacteria were found in combination with an increased pool of fatty acids that indicate fatty acid synthesis and utilisation of the intermediates of the shikimate pathways. This study demonstrates the value of applying a multi-omics approach for ecological assessments, in which a more detailed assessment of physical and chemical contaminants and their impact on the community bacterial biome is obtained.

Structuring educational decisions using the multiple sorting task: An example focusing on international placements in nursing.

Practical examples of the steps involved in the planning and execution of the multiple sorting task are frequently lacking in published reports. This article demonstrates how the multiple sorting task can be used to structure conversations with a group of health professionals planning an international placement for nursing students. Sixteen participants were drawn from diverse professional backgrounds, including academia, clinical practice, government policy, and placement administrators. Participants sorted 17 statements written on cards into categories of their choice and noted why they sorted the cards into these particular groups. Data were analysed using multidimensional scaling and qualitative perspectives. The analysis identified four key themes that detailed the participants' views about international placements. These findings demonstrate how the multiple sorting task can be used to generate information that facilitates the examination of important facets of health care practice that universities could cover in preparing students for international placements.

Differences in carbon source utilisation by orchid mycorrhizal fungi from common and endangered species of Caladenia (Orchidaceae).

Terrestrial orchids depend on orchid mycorrhizal fungi (OMF) as symbionts for their survival, growth and nutrition. The ability of OMF from endangered orchid species to compete for available resources with OMF from common species may affect the distribution, abundance and therefore conservation status of their orchid hosts. Eight symbiotically effective OMF from endangered and more common Caladenia species were tested for their ability to utilise complex insoluble and simple soluble carbon sources produced during litter degradation by growth with different carbon sources in liquid medium to measure the degree of OMF variation with host conservation status or taxonomy. On simple carbon sources, fungal growth was assessed by biomass. On insoluble substrates, ergosterol content was assessed using ultra-performance liquid chromatography (UPLC). The OMF grew on all natural materials and complex carbon sources, but produced the greatest biomass on xylan and starch and the least on bark and chitin. On simple carbon sources, the greatest OMF biomass was measured on most hexoses and disaccharides and the least on galactose and arabinose. Only some OMF used sucrose, the most common sugar in green plants, with possible implications for symbiosis. OMF from common orchids produced more ergosterol and biomass than those from endangered orchids in the Dilatata and Reticulata groups but not in the Patersonii and Finger orchids. This suggests that differences in carbon source utilisation may contribute to differences in the distribution of some orchids, if these differences are retained on site.

The effect of sodium nitroprusside on psychotic symptoms and spatial working memory in patients with schizophrenia: a randomized, double-blind, placebo-controlled trial.

BACKGROUND: Sodium nitroprusside (SNP) has been reported to rapidly reduce psychotic symptoms in patients with schizophrenia. This has the potential to revolutionize treatment for schizophrenia. In this study, we tested the hypothesis that SNP leads to a reduction in psychotic symptoms and an improvement in spatial working memory (SWM) performance in patients with schizophrenia. METHOD: This was a single-centre, randomized, double-blind, placebo-controlled trial performed from 27 August 2014 to 10 February 2016 (clinicaltrials.gov identifier: NCT02176044). Twenty patients with schizophrenia aged 18-60 years with a diagnosis of schizophrenia or schizoaffective disorder were recruited from psychiatric outpatient clinics in the South London and Maudsley NHS Trust, London, UK. Baseline symptoms were measured using the Positive and Negative Syndrome Scale (PANSS) and the 18-item Brief Psychiatric Rating Scale (BPRS-18), and SWM was assessed using the CANTAB computerized test. Participants received either an infusion of SNP (0.5 µg/kg per min for 4 h) or placebo and were re-assessed for symptoms and SWM performance immediately after the infusion, and 4 weeks later. RESULTS: SNP did not lead to any reduction in psychotic symptoms or improvement in SWM performance compared to placebo. CONCLUSIONS: Although this study was negative, it is possible that the beneficial effects of SNP may occur in patients with a shorter history of illness, or with more acute exacerbation of symptoms.

Mental health nurses' views about antipsychotic medication side effects.

WHAT IS KNOWN ON THE SUBJECT?: The only previous quantitative study that examined nurses' use of assessment tools to identify antipsychotic medication side effects found that about 25% of mental health nurses were using assessment tools. No previous studies have examined factors that influence the manner in which mental health nurses assess antipsychotic medication side effects. WHAT THIS PAPER ADDS TO EXISTING KNOWLEDGE?: One-third of the respondents were not aware of any antipsychotic medication side-effect assessment tool, and only one-quarter were currently using an assessment tool. 'Service responsibility' was significantly associated with ongoing use of antipsychotic medication assessment tools, indicating that respondents with more positive attitudes to their service were more likely to continue using antipsychotic medication assessment tools. WHAT ARE THE IMPLICATIONS FOR PRACTICE?: The low level of awareness and use of antipsychotic medication side-effect assessment tools indicates that nursing educational institutions should incorporate more detail about these tools in course content, and emphasize in particular the benefits that result from the use of these tools in clinical practice. Service processes contributed significantly to the use of antipsychotic medication assessment tools, which indicates that managers need to foster workplace cultures that promote routine use of these tools. ABSTRACT: Introduction Limited evidence suggests that only a minority of mental health nurses regularly use standardized assessment tools to assess antipsychotic medication side effects, but the factors that contribute to the non-routine use of these tools remain unknown. Aim To examine Australian mental health nurses' awareness of, and attitudes towards, side-effect assessment tools, and also identify factors the influence the use of these tools. Methods A cross-sectional survey was undertaken through distributing an online questionnaire via email to members of the Australian College of Mental Health Nurses. Completed questionnaires were received from 171 respondents. Linear regression was used to examine the relationship between the 'service responsibility' and 'personal confidence' scale scores, and awareness, previous use and ongoing use of antipsychotic medication assessment tools. Results Only one-quarter of the respondents (26.5%) were currently using an assessment tool. 'Service responsibility' was significantly associated with ongoing use of antipsychotic medication assessment tools (Β = 3.26; 95% CI 0.83-5.69). 'Personal confidence' did not influence the ongoing use of assessment tools (Β = -0.05; 95% CI -1.06-1.50). Implications for clinical practice Stakeholders can incorporate 'service responsibility' processes to foster increased use of assessment tools, which may enhance the identification antipsychotic medication side effects and improve the quality of care for service users.