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We perform a direct numerical simulation (DNS) of interacting Kelvin–Helmholtz instabilities (KHI) that arise at a stratified shear layer where KH billow cores are misaligned or exhibit varying phases along their axes. Significant evidence of these dynamics in early laboratory shear-flow studies by Thorpe (Geophys. Astrophys. Fluid Dyn., vol. 34, 1985, pp. 175–199) and Thorpe (J. Geophys. Res., vol. 92, 1987, pp. 5231–5248), in observations of KH billow misalignments in tropospheric clouds (Thorpe, Q. J. R. Meteorol. Soc., vol. 128, 2002, pp. 1529–1542) and in recent direct observations of such events in airglow and polar mesospheric cloud imaging in the upper mesosphere reveals that these dynamics are common. More importantly, the laboratory and mesospheric observations suggest that these dynamics lead to more rapid and more intense instabilities and turbulence than secondary convective instabilities in billow cores and secondary KHI in stratified braids between and around adjacent billows. To date, however, no simulations exploring the dynamics and energetics of interacting KH billows (apart from pairing) have been performed. Our DNS performed for Richardson number $Ri=0.10$ and Reynolds number $Re=5000$ demonstrates that KHI tubes and knots (i) comprise strong and complex vortex interactions accompanying misaligned KH billows, (ii) accelerate the transition to turbulence relative to secondary instabilities of individual KH billows, (iii) yield significantly stronger turbulence than secondary KHI in billow braids and secondary convective instabilities in KHI billow cores and (iv) expand the suite of secondary instabilities previously recognized to contribute to KHI dynamics and breakdown to turbulence in realistic geophysical environments.
Fritts et al. (J. Fluid Mech., vol. xx, 2022, xx) describe a direct numerical simulation of interacting Kelvin–Helmholtz instability (KHI) billows arising due to initial billow cores that exhibit variable phases along their axes. Such KHI exhibit strong ‘tube and knot’ dynamics identified in early laboratory studies by Thorpe (Geophys. Astrophys. Fluid Dyn., vol. 34, 1985, pp. 175–199). Thorpe (Q.J.R. Meteorol. Soc., vol. 128, 2002, pp. 1529–1542) noted that these dynamics may be prevalent in the atmosphere, and they were recently identified in atmospheric observations at high altitudes. Tube and knot dynamics were found by Fritts et al. (J. Fluid. Mech., 2022) to drive stronger and faster turbulence transitions than secondary instabilities of individual KH billows. Results presented here reveal that KHI tube and knot dynamics also yield energy dissipation rates $\sim$2–4 times larger as turbulence arises and that remain $\sim$2–3 times larger to later stages of the flow evolution, compared with those of secondary convective instabilities (CI) and secondary KHI accompanying KH billows without tube and knot influences. Elevated energy dissipation rates occur due to turbulence transitions by tube and knot dynamics arising on much larger scales than secondary CI and KHI where initial KH billows are misaligned. Tube and knot dynamics also excite large-scale Kelvin ‘twist waves’ that cause vortex tube and billow core fragmentation, more energetic cascades of similar interactions to smaller scales and account for the strongest energy dissipation events accompanying such KH billow evolutions.
Mental disorders are common in people living with HIV (PLWH) but often remain untreated. This study aimed to explore the treatment gap for mental disorders in adults followed-up in antiretroviral therapy (ART) programmes in South Africa and disparities between ART programmes regarding the provision of mental health services.
We conducted a cohort study using ART programme data and linked pharmacy and hospitalisation data to examine the 12-month prevalence of treatment for mental disorders and factors associated with the rate of treatment for mental disorders among adults, aged 15–49 years, followed-up from 1 January 2012 to 31 December 2017 at one private care, one public tertiary care and two pubic primary care ART programmes in South Africa. We calculated the treatment gap for mental disorders as the discrepancy between the 12-month prevalence of mental disorders in PLWH (aged 15–49 years) in South Africa (estimated based on data from the Global Burden of Disease study) and the 12-month prevalence of treatment for mental disorders in ART programmes. We calculated adjusted rate ratios (aRRs) for factors associated with the treatment rate of mental disorders using Poisson regression.
In total, 182 285 ART patients were followed-up over 405 153 person-years. In 2017, the estimated treatment gap for mental disorders was 40.5% (95% confidence interval [CI] 19.5–52.9) for patients followed-up in private care, 96.5% (95% CI 95.0–97.5) for patients followed-up in public primary care and 65.0% (95% CI 36.5–85.1) for patients followed-up in public tertiary care ART programmes. Rates of treatment with antidepressants, anxiolytics and antipsychotics were 17 (aRR 0.06, 95% CI 0.06–0.07), 50 (aRR 0.02, 95% CI 0.01–0.03) and 2.6 (aRR 0.39, 95% CI 0.35–0.43) times lower in public primary care programmes than in the private sector programmes.
There is a large treatment gap for mental disorders in PLWH in South Africa and substantial disparities in access to mental health services between patients receiving ART in the public vs the private sector. In the public sector and especially in public primary care, PLWH with common mental disorders remain mostly untreated.
We evaluated the relationship between local MRSA prevalence rates and antibiotic use across 122 VHA hospitals in 2016. Higher hospital-level MRSA prevalence was associated with significantly higher rates of antibiotic use, even after adjusting for case mix and stewardship strategies. Benchmarking anti-MRSA antibiotic use may need to adjust for MRSA prevalence.
There is limited evidence of the safety and impact of task-shared care for people with severe mental illnesses (SMI; psychotic disorders and bipolar disorder) in low-income countries. The aim of this study was to evaluate the safety and impact of a district-level plan for task-shared mental health care on 6 and 12-month clinical and social outcomes of people with SMI in rural southern Ethiopia.
In the Programme for Improving Mental health carE, we conducted an intervention cohort study. Trained primary healthcare (PHC) workers assessed community referrals, diagnosed SMI and initiated treatment, with independent research diagnostic assessments by psychiatric nurses. Primary outcomes were symptom severity and disability. Secondary outcomes included discrimination and restraint.
Almost all (94.5%) PHC worker diagnoses of SMI were verified by psychiatric nurses. All prescribing was within recommended dose limits. A total of 245 (81.7%) people with SMI were re-assessed at 12 months. Minimally adequate treatment was received by 29.8%. All clinical and social outcomes improved significantly. The impact on disability (standardised mean difference 0.50; 95% confidence interval (CI) 0.35–0.65) was greater than impact on symptom severity (standardised mean difference 0.28; 95% CI 0.13–0.44). Being restrained in the previous 12 months reduced from 25.3 to 10.6%, and discrimination scores reduced significantly.
An integrated district level mental health care plan employing task-sharing safely addressed the large treatment gap for people with SMI in a rural, low-income country setting. Randomised controlled trials of differing models of task-shared care for people with SMI are warranted.
Diagnosis, treatment, and prevention of vector-borne disease (VBD) in pets is one cornerstone of companion animal practices. Veterinarians are facing new challenges associated with the emergence, reemergence, and rising incidence of VBD, including heartworm disease, Lyme disease, anaplasmosis, and ehrlichiosis. Increases in the observed prevalence of these diseases have been attributed to a multitude of factors, including diagnostic tests with improved sensitivity, expanded annual testing practices, climatologic and ecological changes enhancing vector survival and expansion, emergence or recognition of novel pathogens, and increased movement of pets as travel companions. Veterinarians have the additional responsibility of providing information about zoonotic pathogen transmission from pets, especially to vulnerable human populations: the immunocompromised, children, and the elderly. Hindering efforts to protect pets and people is the dynamic and ever-changing nature of VBD prevalence and distribution. To address this deficit in understanding, the Companion Animal Parasite Council (CAPC) began efforts to annually forecast VBD prevalence in 2011. These forecasts provide veterinarians and pet owners with expected disease prevalence in advance of potential changes. This review summarizes the fidelity of VBD forecasts and illustrates the practical use of CAPC pathogen prevalence maps and forecast data in the practice of veterinary medicine and client education.
Introduction: September 2017 saw the launch of the British Columbia (BC) Emergency Medicine Network (EM Network), an innovative clinical network established to improve emergency care across the province. The intent of the EM Network is to support the delivery of evidence-informed, patient-centered care in all 108 Emergency Departments and Diagnostic & Treatment Centres in BC. After one year, the Network undertook a formative evaluation to guide its growth. Our objective is to describe the evaluation approach and early findings. Methods: The EM Network was evaluated on three levels: member demographics, online engagement and member perceptions of value and progress. For member demographics and online engagement, data were captured from member registration information on the Network's website, Google Analytics and Twitter Analytics. Membership feedback was sought through an online survey using a social network analysis tool, PARTNER (Program to Analyze, Record, and Track Networks to Enhance Relationships), and semi-structured individual interviews. This framework was developed based on literature recommendations in collaboration with Network members, including patient representatives. Results: There are currently 622 EM Network members from an eligible denominator of approximately 1400 physicians (44%). Seventy-three percent of the Emergency Departments and Diagnostic and Treatment Centres in BC currently have Network members, and since launch, the EM Network website has been accessed by 11,154 unique IP addresses. Online discussion forum use is low but growing, and Twitter following is high. There are currently 550 Twitter followers and an average of 27 ‘mentions’ of the Network by Twitter users per month. Member feedback through the survey and individual interviews indicates that the Network is respected and credible, but many remain unaware of its purpose and offerings. Conclusion: Our findings underscore that early evaluation is useful to identify development needs, and for the Network this includes increasing awareness and online dialogue. However, our results must be interpreted cautiously in such a young Network, and thus, we intend to re-evaluate regularly. Specific action recommendations from this baseline evaluation include: increasing face-to-face visits of targeted communities; maintaining or accelerating communication strategies to increase engagement; and providing new techniques that encourage member contributions in order to grow and improve content.
Depression is a common disorder characterized by delayed help-seeking, often remaining undetected and untreated.
We sought to estimate the proportion of adults in Kamuli District with depressive symptoms and to assess their help-seeking behaviour.
This was a population-based cross-sectional study conducted in a rural district in Uganda. Sampling of study participants was done using the probability proportional to size method. Screening for depression was done using Patient Health Questionnaire (PHQ-9). The participants who screened positive also reported on whether and where they had sought treatment. Data collected using PHQ-9 was used both as a symptom-based description of depression and algorithm diagnosis of major depression. All data analysis was done using STATA version 13.
With a cut-off score of ⩾10, 6.4% screened positive for current depressive symptoms and 23.6% reported experiencing depressive symptoms in the past 12 months. The majority of individuals who screened positive for current depression (75.6%) were females. In a crude analysis, people with lower education, middle age and low socio-economic status were more likely to have depressive symptoms. Help-seeking was low, with only 18.9% of the individuals who screened positive for current depression having sought treatment from a health worker.
Depressive symptoms are common in the study district with low levels of help-seeking practices. People with lower levels of education, low socio-economic status and those in middle age are more likely to be affected by these symptoms. Most persons with current depression had past history of depressive symptoms.
A combination of intimate partner violence (IPV) and depression is a common feature of the perinatal period globally. Understanding this association can provide indications of how IPV can be addressed or prevented during pregnancy. This paper aims to determine the prevalence and correlates of IPV among pregnant low-income women with depressive symptoms in Khayelitsha, South Africa, and changes in IPV reports during the course of the perinatal period.
This study is a secondary analysis of data collected as part of a randomised controlled trial testing a psychosocial intervention for antenatal depression. IPV, socio-demographic measures, depression and other mental health measures were collected at recruitment (first antenatal visit), 8 months gestation, and 3 and 12 months postpartum. IPV was defined as a sexual or physical violence perpetrated by the participant's partner in the past 3 months. Descriptive statistics are reported.
Of 425 recruited depressed participants, 59 (13.9%) reported IPV at baseline, with physical IPV being the most frequently reported (69.5%). Reported IPV was associated with greater emotional distress, potentially higher food insecurity and higher rates of alcohol abuse. There were clear longitudinal trends in reported IPV with the majority of women no longer reporting IPV postpartum. However, some women reported IPV at later assessment points after not reporting IPV at baseline.
There is a strong association between IPV and depression in pregnancy. IPV reports remit over time for the women in this study, although the reason for this reduction is not clear and requires further investigation.
The treatment gap between the number of people with mental disorders and the number treated represents a major public health challenge. We examine this gap by socio-economic status (SES; indicated by family income and respondent education) and service sector in a cross-national analysis of community epidemiological survey data.
Data come from 16 753 respondents with 12-month DSM-IV disorders from community surveys in 25 countries in the WHO World Mental Health Survey Initiative. DSM-IV anxiety, mood, or substance disorders and treatment of these disorders were assessed with the WHO Composite International Diagnostic Interview (CIDI).
Only 13.7% of 12-month DSM-IV/CIDI cases in lower-middle-income countries, 22.0% in upper-middle-income countries, and 36.8% in high-income countries received treatment. Highest-SES respondents were somewhat more likely to receive treatment, but this was true mostly for specialty mental health treatment, where the association was positive with education (highest treatment among respondents with the highest education and a weak association of education with treatment among other respondents) but non-monotonic with income (somewhat lower treatment rates among middle-income respondents and equivalent among those with high and low incomes).
The modest, but nonetheless stronger, an association of education than income with treatment raises questions about a financial barriers interpretation of the inverse association of SES with treatment, although future within-country analyses that consider contextual factors might document other important specifications. While beyond the scope of this report, such an expanded analysis could have important implications for designing interventions aimed at increasing mental disorder treatment among socio-economically disadvantaged people.
In low-income African countries, ensuring food security for all segments of the population is a high priority. Mental illness is associated consistently with poverty, but there is little evidence regarding the association with food insecurity. The aim of this study was to compare the levels of food insecurity in people with severe mental disorders (SMD) with the general population in a rural African setting with a high burden of food insecurity.
Households of 292 community-ascertained people with a specialist-confirmed diagnosis of SMD (including schizophrenia and bipolar disorder) were compared with 284 households without a person with SMD in a rural district in south Ethiopia. At the time of the study, no mental health services were available within the district. Food insecurity was measured using a validated version of the Household Food Insecurity Access Scale. Disability was measured using the World Health Organisation Disability Assessment Schedule 2.0.
Severe household food insecurity was reported by 32.5% of people with SMD and 15.9% of respondents from comparison households: adjusted odds ratio 2.82 (95% confidence interval 1.62 to 4.91). Higher annual income was associated independently with lower odds of severe food insecurity. When total disability scores were added into the model, the association between SMD and food insecurity became non-significant, indicating a possible mediating role of disability.
Efforts to alleviate food insecurity need to target people with SMD as a vulnerable group. Addressing the disabling effects of SMD would also be expected to reduce food insecurity. Access to mental health care integrated into primary care is being expanded in this district as part of the Programme for Improving Mental health carE (PRIME). The impact of treatment on disability and food insecurity will be evaluated.
There is increasing international recognition of the need to build capacity to strengthen mental health systems. This is a fundamental goal of the ‘Emerging mental health systems in low- and middle-income countries’ (Emerald) programme, which is being implemented in six low- and middle-income countries (LMICs) (Ethiopia, India, Nepal, Nigeria, South Africa, Uganda). This paper discusses Emerald's capacity-building approaches and outputs for three target groups in mental health system strengthening: (1) mental health service users and caregivers, (2) service planners and policy-makers, and (3) mental health researchers. When planning the capacity-building activities, the approach taken included a capabilities/skills matrix, needs assessments, a situational analysis, systematic reviews, qualitative interviews and stakeholder meetings, as well as the application of previous theory, evidence and experience. Each of the Emerald LMIC partners was found to have strengths in aspects of mental health system strengthening, which were complementary across the consortium. Furthermore, despite similarities across the countries, capacity-building interventions needed to be tailored to suit the specific needs of individual countries. The capacity-building outputs include three publicly and freely available short courses/workshops in mental health system strengthening for each of the target groups, 27 Masters-level modules (also open access), nine Emerald-linked PhD students, two MSc studentships, mentoring of post-doctoral/mid-level researchers, and ongoing collaboration and dialogue with the three groups. The approach taken by Emerald can provide a potential model for the development of capacity-building activities across the three target groups in LMICs.
There is convincing evidence that lower socioeconomic position is associated with increased risk of mental disorders. However, the mechanisms involved are not well understood. This study aims to elucidate the causal pathways between socioeconomic position and depression symptoms in South African adults. Two possible causal theories are examined: social causation, which suggests that poor socioeconomic conditions cause mental ill health; and social drift, which suggests that those with poor mental health are more likely to drift into poor socioeconomic circumstances.
The study used longitudinal and cross-sectional observational data on 3904 adults, from a randomised trial carried out in 38 primary health care clinics between 2011 and 2012. Structural equation models and counterfactual mediation analyses were used to examine causal pathways in two directions. First, we examined social causation pathways, with language (a proxy for racial or ethnic category) being treated as an exposure, while education, unemployment, income and depression were treated as sequential mediators and outcomes. Second, social drift was explored with depression treated as a potential influence on health-related quality of life, job loss and, finally, income.
The results suggest that the effects of language on depression at baseline, and on changes in depression during follow-up, were mediated through education and income but not through unemployment. Adverse effects of unemployment and job loss on depression appeared to be mostly mediated through income. The effect of depression on decreasing income appeared to be mediated by job loss.
These results suggest that both social causation and social selection processes operate concurrently. This raises the possibility that people could get trapped in a vicious cycle in which poor socioeconomic conditions lead to depression, which, in turn, can cause further damage to their economic prospects. This study also suggests that modifiable factors such as income, employment and treatable depression are suitable targets for intervention in the short to medium term, while in the longer term reducing inequalities in education will be necessary to address the deeply entrenched inequalities in South Africa.
We investigated the frequency and determinants of guideline-discordant antibiotic prescribing in outpatients with respiratory infections or cystitis. Antibiotic prescribing was guideline discordant in 60% of patients. The most common reason for discordance was prescribing an antibiotic when not indicated. In a multivariate analysis, physicians in training had the highest likelihood of guideline-concordant antibiotic prescribing.
Suicidal behaviour is an under-reported and hidden cause of death in most low- and middle-income countries (LMIC) due to lack of national systematic reporting for cause-specific mortality, high levels of stigma and religious or cultural sanctions. The lack of information on non-fatal suicidal behaviour (ideation, plans and attempts) in LMIC is a major barrier to design and implementation of prevention strategies. This study aims to determine the prevalence of non-fatal suicidal behaviour within community- and health facility-based populations in LMIC.
Twelve-month prevalence of suicidal ideation, plans and attempts were established through community samples (n = 6689) and primary care attendees (n = 6470) from districts in Ethiopia, Uganda, South Africa, India and Nepal using the Composite International Diagnostic Interview suicidality module. Participants were also screened for depression and alcohol use disorder.
We found that one out of ten persons (10.3%) presenting at primary care facilities reported suicidal ideation within the past year, and 1 out of 45 (2.2%) reported attempting suicide in the same period. The range of suicidal ideation was 3.5–11.1% in community samples and 5.0–14.8% in health facility samples. A higher proportion of facility attendees reported suicidal ideation than community residents (10.3 and 8.1%, respectively). Adults in the South African facilities were most likely to endorse suicidal ideation (14.8%), planning (9.5%) and attempts (7.4%). Risk profiles associated with suicidal behaviour (i.e. being female, younger age, current mental disorders and lower educational and economic status) were highly consistent across countries.
The high prevalence of suicidal ideation in primary care points towards important opportunities to implement suicide risk reduction initiatives. Evidence-supported strategies including screening and treatment of depression in primary care can be implemented through the World Health Organization's mental health Global Action Programme suicide prevention and depression treatment guidelines. Suicidal ideation and behaviours in the community sample will require detection strategies to identify at risks persons not presenting to health facilities.
We are a group of researchers and clinicians with collective experience in child survival, nutrition, cognitive and social development, and treatment of common mental conditions. We join together to welcome an expanded definition of child development to guide global approaches to child health and overall social development. We call for resolve to integrate maternal and child mental health with child health, nutrition, and development services and policies, and see this as fundamental to the health and sustainable development of societies. We suggest specific steps toward achieving this objective, with associated global organizational and resource commitments. In particular, we call for a Global Planning Summit to establish a much needed Global Alliance for Child Development and Mental Health in all Policies.
We analysed the psychometric properties of two published self-report suicide assessment competency rating scales – the Suicide Competency Inventory (SCI) and the Suicide Competency Assessment Form (SCAF) – in a sample of 93 public-sector vocational rehabilitation support staff from six states in the United States. Both measures demonstrated very good to excellent internal consistency in our sample. Exploratory factor analysis with principal axis factoring indicated the SCI loads on a two-factor model in this sample, as opposed to the three-factor model proposed by the measure's authors. The SCAF loaded on a single factor, consistent with the theoretical model proposed by the original authors. The SCI and SCAF were highly correlated with each other, providing initial evidence of convergent construct validity. These results provide initial support for the use of these measures as a reliable and valid means of assessing perceived suicide assessment competency in vocational rehabilitation support staff.