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Developing integrated mental health services focused on the needs of children and young people is a key policy goal in England. The THRIVE Framework and its implementation programme, i-THRIVE, are widely used in England. This study examines experiences of staff using i-THRIVE, estimates its effectiveness, and assesses how local system working relationships influence programme success.
Methods
This evaluation uses a quasi-experimental design (10 implementation and 10 comparison sites.) Measurements included staff surveys and assessment of ‘THRIVE-like’ features of each site. Additional site-level characteristics were collected from health system reports. The effect of i-THRIVE was evaluated using a four-group propensity-score-weighted difference-in-differences model; the moderating effect of system working relationships was evaluated with a difference-in-difference-in-differences model.
Results
Implementation site staff were more likely to report using THRIVE and more knowledgeable of THRIVE principles than comparison site staff. The mean improvement of fidelity scores among i-THRIVE sites was 16.7, and 8.8 among comparison sites; the weighted model did not find a statistically significant difference. However, results show that strong working relationships in the local system significantly enhance the effectiveness of i-THRIVE. Sites with highly effective working relationships showed a notable improvement in ‘THRIVE-like’ features, with an average increase of 16.41 points (95% confidence interval: 1.69–31.13, P-value: 0.031) over comparison sites. Sites with ineffective working relationships did not benefit from i-THRIVE (−2.76, 95% confidence interval: − 18.25–12.73, P-value: 0.708).
Conclusions
The findings underscore the importance of working relationship effectiveness in the successful adoption and implementation of multi-agency health policies like i-THRIVE.
Fast electron generation and transport in high-intensity laser–solid interactions induces X-ray emission and drives ion acceleration. Effective production of these sources hinges on an efficient laser absorption into the fast electron population and control of divergence as the beam propagates through the target. Nanowire targets can be employed to increase the laser absorption, but it is not yet clear how the fast electron beam properties are modified. Here we present novel measurements of the emittance of the exiting fast electron beam from irradiated solid planar and nanowire targets via a pepper-pot diagnostic. The measurements indicate a greater fast electron emittance is obtained from nanowire targets. Two-dimensional particle-in-cell simulations support this conclusion, revealing beam defocusing at the wire–substrate boundary, a higher fast electron temperature and transverse oscillatory motion around the wires.
Being married may protect late-life cognition. Less is known about living arrangement among unmarried adults and mechanisms such as brain health (BH) and cognitive reserve (CR) across race and ethnicity or sex/gender. The current study examines (1) associations between marital status, BH, and CR among diverse older adults and (2) whether one’s living arrangement is linked to BH and CR among unmarried adults.
Method:
Cross-sectional data come from the Washington Heights-Inwood Columbia Aging Project (N = 778, 41% Hispanic, 33% non-Hispanic Black, 25% non-Hispanic White; 64% women). Magnetic resonance imaging (MRI) markers of BH included cortical thickness in Alzheimer’s disease signature regions and hippocampal, gray matter, and white matter hyperintensity volumes. CR was residual variance in an episodic memory composite after partialing out MRI markers. Exploratory analyses stratified by race and ethnicity and sex/gender and included potential mediators.
Results:
Marital status was associated with CR, but not BH. Compared to married individuals, those who were previously married (i.e., divorced, widowed, and separated) had lower CR than their married counterparts in the full sample, among White and Hispanic subgroups, and among women. Never married women also had lower CR than married women. These findings were independent of age, education, physical health, and household income. Among never married individuals, living with others was negatively linked to BH.
Conclusions:
Marriage may protect late-life cognition via CR. Findings also highlight differential effects across race and ethnicity and sex/gender. Marital status could be considered when assessing the risk of cognitive impairment during routine screenings.
There is an urgent need for climate change–informed decision-making and adaptation actions for cultural heritage. Challenges arise in incorporating and balancing multiple considerations, including robust understandings of climate change vulnerability, the objectives of current management paradigms, the need for meaningful engagement, the risk of maladaptation, and constrained resources to implement. We offer a conceptual framework and guide to integrate climate science and cultural heritage management to produce a range of adaptation actions for cultural heritage, categorized as Acclimate, Dislocate, Abandon, Protect, and Tell the Story (ADAPT) approaches. The ADAPT framework is intended to aid archaeologists and other cultural heritage managers in developing and evaluating possible adaptation actions that directly respond to findings from climate change vulnerability assessments, critically integrating management postures and constraints, and coproducing climate change adaptations with Indigenous rightsholders and community stakeholders.
Much has been made of the decline in population mental health over COVID but most studies show this just exacerabted a loing term trend This has predominnatly been attributed to changes in adolescent mental health over the past decade but there ahs been little evalaution of whether this post Millenium cohort was the first to demonstrate such a decline
Objectives
This study investigates to what extent mental differs in people born in different decades – i.e., possible birth cohort differences in the mental health of the popualtion over the past two decades To remove the linear dependency and identify any differences in trends between cohorts, we model mental health for each cohort as a nonlinear smooth function of age in an age-cohort model.
Methods
This analysis draws on 20 annual waves of the Household Income and Labour Dynamic in Australia (HILDA) survey.,is a nationally representative household panel that commenced in 2001 with 13,969 participants. The birth cohort of each person was defined by the decade of birth year(1940s, 1950s, etc). Mental ill health was assessed with the MHI5 from the SF36, in each wave and K10 from alternate waves. We estimate and compare penalized smooth trends in mental health for each cohort using restricted maximum likelihood (REML) using generalized additive mixed modelling (GAMM). Cohort effects are captured by directly estimating the differences between the smooth age trends of adjacent cohorts.
Results
Later cohorts were more likely to have poorer mental health, higher distress, more likely to be single and unemployed, and less likely to be chronically ill or disabled. Mental health was worse for younger age-groups in each survey year, and this discrepancy is much greater in more recent surveys - consistent with a birth cohort effect. Millennials (those born in the early 1990s) had a lower score at the same age as earlier generations, and the later cohorts do not show the age-related improvement seen in other earlier cohorts as they aged. At age 30 the average MHI-5 score of those born in the 1990s was 67, compared to 72.5 and 74 for people born in the 1980s and 1970s.
Conclusions
The deterioration in mental health over time which has been reported in large cross-sectional surveys, likely reflects cohort-specific effects related to the experiences of young people born in the Millennial generation and, to a lesser extent, those from the immediately prior cohort born in the1980s. We need to understand whether later cohorts are less resilient to similar risk factors experienced by earlier cohorts or whether they experience more and/or a greater severity of risks for mental ill-health. Such evidence is critical if the deteriorating pattern of mental health is to be arrested.
Irritable bowel syndrome (IBS) is a chronic and relapsing gastrointestinal condition which negatively impacts quality of life(1). Dietary triggers are common and dietary management is central to the IBS treatment pathway with dietitians being the main education providers for patients(2). The aim of this study was to explore the perceptions of dietitians towards current practices in IBS services in clinical settings across the UK.
Qualitative semi-structured interviews were undertaken to explore current practices, barriers, and facilitators to dietetic practice and expected treatment outcomes. Eligible participants were dietitians specialising in IBS and working in the National Health System (NHS) in the UK. Interviews were held virtually. Audio was recorded and transcribed following intelligent transcription. Data were analysed using template analysis (3).
Thirteen dietitians (n=12 female) specialising in gastroenterology consented to participate in the study. Dietitians were working in various NHS Trusts across the country (Southeast England n=3; Southwest England n=3; Northwest England n=2; Northeast England n=1; West Midlands n=1; Southwest Wales n=1 and Southcentral Scotland n=2). Ten out of 13 dietitians had more than five years of experience in IBS management. Three main themes emerged: 1) Dietetic services as part of IBS referral pathways; 2) Practices in relation to dietetic services and 3) Implications of services on patients’ expectations and feelings. Each main theme had subthemes to facilitate the description and interpretation of data. The increasing number of IBS referrals to dietitians and the need for accurate and timely IBS diagnosis and specialist IBS dietitians was reported, alongside the use of digital innovation to facilitate practice and access to dietetic care. The use of Internet as a source of (mis)information by patients and the limited time available for educating patients were identified as potential barriers to dietetic practice. Dietitians follow a patient-centred approach to dietary counselling and recognise the negative implications of perceived IBS-related stigma by patients on their feelings and treatment expectations.
The study identified areas and practices which can facilitate access to dietetic services and patient- centred care in IBS management as outlined in guidelines (4).
Social support may protect against Alzheimer’s disease and related dementias (ADRD), potentially through emotional or instrumental support elements. Black and Hispanic/Latinx older adults bear a disproportionate burden of ADRD. However, independent effects of emotional and instrumental support on cognition, a primary indicator of ADRD risk, are largely understudied in these groups. Guided by the differential vulnerability hypothesis – the theoretical framework which posits that systemic racism disadvantages Black and Hispanic/Latinx individuals’ health – we hypothesize that emotional and instrumental support may be particularly important to protect against worse cognition for Black and Hispanic/Latinx older adults, who often have fewer resources due to these inequalities (e.g., wealth, educational opportunities) to otherwise maintain health. Using the NIH Toolbox Emotion Module measures of emotional (e.g., the extent to which individuals can rely on others in challenging times) and instrumental support (e.g., the extent to which individuals can rely on others for assistance in daily activities), we aimed to identify positive social support factors (i.e., emotional and instrumental support) that may protect against ADRD risk (i.e., longitudinal executive function and memory performance) among Black and Hispanic/Latinx older adults.
Participants and Methods:
Participants were 362 Black and 265 Hispanic/Latinx adults aged 65-89 (63% female, average age=75) from the Kaiser Healthy Aging and Diverse Life Experiences (KHANDLE) Study who completed baseline and up to two additional waves of assessments (every 1.5 years), including questionnaires, neuropsychological evaluations, and the NIH toolbox. Predictors included baseline covariates (i.e., age, language of test administration, gender, education, income, self-rated health) and NIH toolbox emotional and instrumental support variables. Outcomes were baseline and longitudinal memory (visual and verbal episodic memory) and executive functioning (verbal fluency and working memory) composites from the Spanish and English Neuropsychological Assessment Scales (SENAS). Latent growth curve models were conducted separately in Black and Hispanic/Latinx participants to estimate effects of emotional and instrumental support on baseline cognition and subsequent change in each domain.
Results:
Black participants reported greater emotional support. There were no group differences in levels of instrumental support. Greater instrumental support was associated with better initial memory (standardized β= .194, 95%CI: [.063, .325]) among Black participants but not among Hispanic/Latinx participants. In Hispanic/Latinx participants, greater emotional support was associated with better initial executive functioning (standardized β= .215, 95%CI: [.079, .350]. Emotional support was not associated with either cognitive domain in Black participants. There were no associations between emotional or instrumental support on cognitive change in either group.
Conclusions:
Results point to differences between Black and Hispanic/Latinx older adults in the impact of specific aspects of social support on different cognitive domains. Positive associations between instrumental support and baseline memory in Black participants and between emotional support and executive functioning in Hispanic/Latinx participants suggest unique cognitive consequences of social support across groups. Differences in the role of specific types of social supports may be useful in identifying intervention targets specifically for Black and Hispanic/Latinx older adults, who are disproportionately affected by ADRD. Future research will examine these constructs using multiple group models to test these associations more rigorously.
Gender- and sexuality-minoritised (GSM) adolescents are at increased risk of self-harm and suicidal behaviours compared with their cisgender and heterosexual peers. This increased risk is thought to be explained in part by exposure to stigma and societal oppression. Dialectical behaviour therapy (DBT) is an evidence-based intervention for self-harm and suicidal behaviour that may have advantages for supporting GSM young people in distress. No study has yet sought to understand what GSM-associated difficulties may be important to consider in DBT for adolescents, or the experiences of GSM young people in a standard DBT programme. Therefore, this study aimed to understand the experiences of GSM young people in DBT and what difficulties and dilemmas associated with their gender and sexuality diversity were thought by them to be important to target in DBT. Qualitative interviews were conducted with 14 GSM young people in a comprehensive DBT programme and were analysed using reflexive thematic analysis. The analysis was supported by two further GSM young people who had finished DBT. The findings were split into three over-arching themes (Identity, Impact of Others, and Space for Sexual and Gender Identity in DBT), each with themes within. The identity-based theme included ‘identity confusion and acceptance’; the relationship-based themes included ‘cis-Heterosexism’ and ‘community connectedness’; and the space within DBT themes included ‘negotiating focus and targeting in DBT’ and ‘creating safety in DBT’. Findings are discussed in relation to implications and recommendations for therapists working with GSM young people within and outside of DBT.
Key learning aims
(1) To learn about what gender- and sexuality-minoritised (GSM) young people consider to be important GSM-associated contributors to distress and thus potential treatment targets in DBT.
(2) To learn about what GSM young people felt were barriers to negotiating GSM-associated difficulties as a focus in DBT and how safety was created in the therapeutic relationship.
(3) To consider potential implications and recommendations for improvements to practice when supporting GSM young people in therapy.
Debate is ongoing on the efficacy of cognitive behavior therapy (CBT) for myalgic encephalomyelitis or chronic fatigue syndrome (ME/CFS). With an individual patient data (IPD) meta-analysis we investigated whether the effect of CBT varied by patient characteristics. These included post-exertional malaise (PEM), a central feature of ME/CFS according to many. We searched for randomized controlled trials similar with respect to comparison condition, outcomes and treatment-protocol. Moderation on fatigue severity (Checklist Individual Strength, subscale fatigue severity), functional impairment (Sickness Impact Profile-8) and physical functioning (Short Form-36, subscale physical functioning) was investigated using linear mixed model analyses and interaction tests. PROSPERO (CRD42022358245). Data from eight trials (n = 1298 patients) were pooled. CBT showed beneficial effects on fatigue severity (β = −11.46, 95% CI −15.13 to −7.79); p < 0.001, functional impairment (β = −448.40, 95% CI −625.58 to −271.23); p < 0.001; and physical functioning (β = 9.64, 95% CI 3.30 to 15.98); p < 0.001. The effect of CBT on fatigue severity varied by age (pinteraction = 0.003), functional impairment (pinteraction = 0.045) and physical activity pattern (pinteraction = 0.027). Patients who were younger, reported less functional impairments and had a fluctuating activity pattern benefitted more. The effect on physical functioning varied by self-efficacy (pinteraction = 0.025), with patients with higher self-efficacy benefitting most. No other moderators were found. It can be concluded from this study that CBT for ME/CFS can lead to significant reductions of fatigue, functional impairment, and physical limitations. There is no indication patients meeting different case definitions or reporting additional symptoms benefit less from CBT. Our findings do not support recent guidelines in which evidence from studies not mandating PEM was downgraded.
Scalable methods are required for population dietary monitoring. The Supermarket Transaction Records In Dietary Evaluation (STRIDE) study compares dietary estimates from supermarket transactions with an online FFQ.
Design:
Participants were recruited in four waves, accounting for seasonal dietary variation. Purchases were collected for 1 year during and 1 year prior to the study. Bland–Altman agreement and limits of agreement (LoA) were calculated for energy, sugar, fat, saturated fat, protein and sodium (absolute and relative).
Setting:
This study was partnered with a large UK retailer.
Participants:
Totally, 1788 participants from four UK regions were recruited from the retailer’s loyalty card customer database, according to breadth and frequency of purchases. Six hundred and eighty-six participants were included for analysis.
Results:
The analysis sample were mostly female (72 %), with a mean age of 56 years (sd 13). The ratio of purchases to intakes varied depending on amounts purchased and consumed; purchases under-estimated intakes for smaller amounts on average, but over-estimated for larger amounts. For absolute measures, the LoA across households were wide, for example, for energy intake of 2000 kcal, purchases could under- or over-estimate intake by a factor of 5; values could be between 400 kcal and 10000 kcal. LoA for relative (energy-adjusted) estimates were smaller, for example, for 14 % of total energy from saturated fat, purchase estimates may be between 7 % and 27 %.
Conclusions:
Agreement between purchases and intake was highly variable, strongest for smaller loyal households and for relative values. For some customers, relative nutrient purchases are a reasonable proxy for dietary composition indicating utility in population-level dietary research.
Adverse childhood experiences (ACEs) may be a risk factor for later-life cognitive disorders such as dementia; however, few studies have investigated underlying mechanisms, such as cardiovascular health and depressive symptoms, in a health disparities framework.
Method:
418 community-dwelling adults (50% nonHispanic Black, 50% nonHispanic White) aged 55+ from the Michigan Cognitive Aging Project retrospectively reported on nine ACEs. Baseline global cognition was a z-score composite of five factor scores from a comprehensive neuropsychological battery. Depressive symptoms were assessed using the Center for Epidemiologic Studies Depression Scale. Cardiovascular health was operationalized through systolic blood pressure. A mediation model controlling for sociodemographics, childhood health, and childhood socioeconomic status estimated indirect effects of ACEs on global cognition via depressive symptoms and blood pressure. Racial differences were probed via t-tests and stratified models.
Results:
A negative indirect effect of ACEs on cognition was observed through depressive symptoms [β = −.040, 95% CI (−.067, −.017)], but not blood pressure, for the whole sample. Black participants reported more ACEs (Cohen’s d = .21), reported more depressive symptoms (Cohen’s d = .35), higher blood pressure (Cohen’s d = .41), and lower cognitive scores (Cohen’s d = 1.35) compared to White participants. In stratified models, there was a negative indirect effect through depressive symptoms for Black participants [β = −.074, 95% CI (−.128, −.029)] but not for White participants.
Conclusions:
These results highlight the need to consider racially patterned contextual factors across the life course. Such factors could exacerbate the negative impact of ACEs and related mental health consequences and contribute to racial disparities in cognitive aging.
Thirteen overwintered juvenile hedgehogs (six male, seven female) were released in an area of farm land and gardens on Jersey, Channel Islands. Six (three of each sex) were originally from the same area, the rest came from other parts of the island. They were radio-tracked and monitored regularly for 6 weeks to investigate survival and especially whether ‘site-native’ animals and those from elsewhere differed in respect of their propensity to disperse widely following release. All animals survived at least 4 weeks and 10 were known to be alive after 6 weeks. The fate of the others is unknown, but there is no reason to believe that any of them suffered an early death.
Male hedgehogs used new nests more frequently than females. All remained within 400m of the release point for at least a month, some were still within 200m 6 weeks post-release. Five hedgehogs dispersed, travelling at least 400m from the release point. Four of these were males, including one recaptured 5.2km away. Dispersal seemed to be more related to sex than origin. All animals lost weight initially, but most stabilized after 2-3 weeks; proportionately more weight was lost by larger animals. None was seen to use supplementary food put out for them, despite weight losses, and no aggressive interactions with wild conspecifics were noted. Despite all the animals being naïve juveniles, with little or no previous experience of life in the wild, none were killed by road traffic. Positive conclusions from previous studies concerning the success and welfare implications of releasing hedgehogs after care in captivity are confirmed.
Full ‘rehabilitation’ of sick and injured wild animals should include restoration to the wild. Few attempts have been made to discover the fate of released ‘rehabilitated’ animals, a significant omission in terms of animal welfare. They may die, unable to find adequate food or nest sites in unfamiliar places. They may be ostracized or even attacked by wild resident conspecifics.
Eight ‘rehabilitated’ hedgehogs (Erinaceus europaeus) were released into farmland and radio-tracked to monitor their movements and nesting; they were also weighed frequently. Three wild hedgehogs caught on site were studied in parallel.
Only one animal remained close to the release site throughout the eight week study. The rest scattered, perhaps seeking more familiar terrain. One animal died, possibly not having fully recovered from its original disorder. Of the seven others, three survived at least seven weeks, but two then met with accidental deaths (drowning and road kill). Contact was lost with four animals, but circumstances suggested that they were probably still alive at least five weeks after release. There was no evidence of negative interaction with local wild hedgehogs nor any indication of difficulty with foraging, nesting or finding their nests again. Body-weights were generally maintained or increased. It is concluded that rehabilitated adult hedgehogs can probably cope well with release.
Many juvenile hedgehogs (Erinaceus europaeus) are ‘rehabilitated’ with little or no previous experience of life in the wild. A study is described in which twelve such animals were monitored after release in Devon. They quickly learned their way about, built nests and found them again, and interacted normally with each other and with wild conspecifics. While several showed significant weight loss, this represented only the excess accumulated in captivity. Deaths caused by a predator (badger) and motor cars suggest that captives destinedfor release should not be allowed to become tame and unwary. However, deaths are to be expected in natural circumstances and at least one third of these animals survived beyond the nine-week study, despite having no previous experience of life in the wild. This supports the belief that, although deaths are to be expected, rehabilitating hedgehogs (even naïve juveniles) is possible and worthwhile.
Insomnia and disturbed sleep are more common in autistic adults compared with non-autistic adults, contributing to significant social, psychological and health burdens. However, sleep intervention research for autistic adults is lacking.
Aims:
The aim of the study was to implement an acceptance and commitment therapy group insomnia intervention (ACT-i) tailored for autistic adults to examine its impact on insomnia and co-occurring mental health symptoms.
Method:
Eight individuals (6 male, 2 female) aged between 18 and 70 years, with a clinical diagnosis of autism spectrum disorder, and scores ranging from 9 to 26 on the Insomnia Severity Index (ISI) participated in the trial. Participants were assigned to one of two intervention groups (4 per group) within a multiple baseline over time design for group. Participants completed questionnaires pre-intervention, post-intervention, and at 2-month follow-up, actigraphy 1 week prior to intervention and 1 week post-intervention, and a daily sleep diary from baseline to 1 week post-intervention, and 1 week at follow-up.
Results:
At a group level there were significant improvements in ISI (λ2=10.17, p=.006) and HADS-A (anxiety) (λ2=8.40, p=.015) scores across the three time points. Clinically reliable improvement occurred for ISI scores (n=5) and HADS-A scores (n=4) following intervention. Client satisfaction indicated that ACT-i was an acceptable intervention to the participants (median 4 out of 5).
Conclusions:
This pilot study with eight autistic adults indicates that ACT-i is both an efficacious and acceptable intervention for reducing self-reported insomnia and anxiety symptoms in autistic adults.
Educational attainment is a well-documented predictor of later-life cognition, but less is known about upstream contextual factors. This study aimed to identify which early-life contextual factors uniquely predict later-life global cognition and whether educational attainment mediates these relationships.
Method:
Participants were drawn from the Michigan Cognitive Aging Project (N = 485; Mage = 63.51; SDage = 3.13; 50% non-Hispanic Black). Early-life exposures included U.S. region of elementary school (Midwest, South, Northeast), average parental education, household composition (number of adults (1, 2, 3+), number of children), school racial demographics (predominantly White, predominantly Black, diverse), self-reported educational quality, and school type (public/private). Later-life global cognition was operationalized with a factor score derived from a comprehensive neuropsychological battery. Sequential mediation models controlling for sociodemographics estimated total, direct, and indirect effects of early-life contextual factors on cognition through educational attainment (years).
Results:
Higher educational quality, higher parental education, and attending a private school were each associated with better cognition; attending a predominantly Black or diverse school and reporting three or more adults in the household were associated with lower cognition. After accounting for educational attainment, associations remained for educational quality, school type, and reporting three or more adults in the household. Indirect effects through educational attainment were observed for school region, educational quality, school racial demographics, and parental education.
Conclusions:
School factors appear to consistently predict later-life cognition more than household factors, highlighting the potential long-term benefits of school-level interventions for cognitive aging. Future research should consider additional mediators beyond educational attainment such as neighborhood resources and childhood adversity.
Myringoplasty success rate is estimated to be between 60 and 90 per cent. Factors predicting success include the choice of graft and use of auditory canal packing. This study aimed to determine the intra-operative factors associated with endoscopic myringoplasty success.
Methods
A retrospective review of all endoscopic myringoplasty cases between January 2017 and January 2020 was undertaken. Data were collected on: patient demographics, tympanic membrane perforation size, intra-operative details, audiology and post-operative outcomes.
Results
There was no significant difference in graft success rates between cases using bismuth iodoform paraffin paste and Spongostan packing (86.7 per cent vs 84.9 per cent, respectively). Conchal cartilage graft had a higher success rate (100.0 per cent) compared with Biodesign grafting biomaterial (66.7 per cent), but was not superior to tragal cartilage (84.6 per cent) or temporalis fat or fascia (80.0 per cent).
Conclusion
Spongostan packing is equivalent to bismuth iodoform paraffin paste in terms of endoscopic myringoplasty success rate. Although conchal cartilage graft had higher success rates, it was not statistically significantly different from tragal cartilage.
Constant-flux gravity currents of viscoplastic fluid remain axisymmetric when extruded onto a dry horizontal plane. However, if the plane is coated with a shallow layer of water, the current suffers a dramatic non-axisymmetric instability in which localized $v$-shaped cuts appear in the outer edge where the viscoplastic fluid is in contact with water. These ‘fractures’ lengthen and guide the subsequent radial outflow, leading to distinctive flower-like patterns. This pattern formation process is illustrated for two viscoplastic materials, an aqueous suspension of Carbopol, and a mixture of water and joint compound (a kaolin-based, commercially available product). The fracturing spreads over the entire upper surface of the current when deeper water baths are used, complicating the extrusion patterns. The instability can be removed entirely when the ambient water layer is replaced by an immiscible liquid of comparable viscosity, indicating that the presence of water at the surface is key to the pattern formation process. We conjecture that the underlying mechanism is the fracture under tension of the viscoplastic material, exacerbated by the ambient water.