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The first compilations of Proterozoic eukaryote diversity, published in the 1980s showed a dramatic peak in the Tonian Period (1000–720 Ma), interpreted as the initial radiation of eukaryotes in the marine realm. Over the decades, new discoveries filled in the older part of the record and the peak diminished, but the idea of a Tonian radiation of eukaryotes has remained strong, and is now widely accepted as fact. We present a new diversity compilation based on 181 species and 713 species occurrences from 145 formations ranging in age from 1890 Ma to 720 Ma and find a significant increase in diversity in the Tonian. However, we also find that the number of eukaryotic species through time is highly correlated with the number of formations in our dataset (i.e. eukaryote-bearing formations) through time. This correlation is robust to interpretations of eukaryote affinity, bin size, and bin boundaries. We also find that within-assemblage diversity—a measure thought to circumvent sampling bias—is related to the number of eukaryote-bearing formations through time. Biomarkers show a similar pattern to body fossils, where the rise of eukaryotic biosignatures correlates with increased sampling. We find no evidence that the proportion of eukaryote-bearing versus all fossiliferous formations changed through the Proterozoic, as might be expected if the correlation reflected an increase in eukaryote diversity driving an increase in the number of eukaryote-bearing formations. Although the correlation could reflect a common cause such as changes in sea level driving both diversification and an increase in sedimentary rock volume, we favor the explanation that the pattern of early eukaryote diversity is driven by variations in paleontological sampling.
Through the colonial period in Sāmoa, Christian morality was embedded into Samoan culture. This transformed gender relations, introducing a new, well-disciplined figure of the Samoan woman. Because of this shift, we argue for the need to develop Samoan feminist thought, which is as much a development of new thinking as it is a return to and restoration of Samoan feminist thought already in existence within Indigenous Samoan cosmologies. We contextualize this thinking within a coalition of Pacific, Indigenous, Black, and women of color feminist thinkers. As feminist scholars have established, feminism doesn’t resonate or work with a simple copy and paste to culture and context. Rather, feminisms are contextual and subjective. It is thus imperative that those from within various contexts continue to broaden understandings and conceptualizations of feminism/s, which work toward demarcating spaces for feminist thought that illuminates multiple, diverse, and intersecting subjectivities and positionalities. As such, the task for us as Samoan women, people, and communities is to develop a feminist space that encompasses and fosters a by-us, for-us, with-us approach that challenges coloniality in Sāmoa and articulates feminist possibilities and futures.
Adaptive radiotherapy (ART) is commonly used to mitigate effects of anatomical change during head and neck (H&N) radiotherapy. The process of identifying patients for ART can be subjective and resource-intensive. This feasibility project aims to design and validate a pipeline to automate the process and use it to assess the current clinical pathway for H&N treatments.
Methods:
The pipeline analysed patients’ on-set cone-beam CT (CBCT) scans to identify inter-fractional anatomical changes. CBCTs were converted into synthetic CTs, contours were automatically generated, and the original plan was recomputed. Each synthetic CT was evaluated against a set of dosimetric goals, with failed goals causing an ART recommendation.
To validate pipeline performance, a ‘gold standard’ was synthesised by recomputing patients’ original plans on a rescan-CT acquired during treatment and identifying failed clinical goals. The pipeline sensitivity and specificity compared to this ‘gold standard’ were calculated for 12 ART patients. The pipeline was then run on a cohort of 12 ART and 14 non-ART patients, and its sensitivity and specificity were instead calculated against the clinical decision made.
Results:
The pipeline showed good agreement with the synthesised ‘gold standard’ with an optimum sensitivity of 0·83 and specificity of 0·67. When run over a cohort containing both ART and non-ART patients and assessed against the subjective clinical decision made, the pipeline showed no predictive power (sensitivity: 0·58, specificity: 0·47).
Conclusions:
Good agreement with the ‘gold standard’ gives confidence in pipeline performance and disagreement with clinical decisions implies implementation could help standardise the current clinical pathway.
Late-life affective disorders (LLADs) are common and are projected to increase by 2050. There have been several studies linking late-life depression to an increased risk of dementia, but it is unclear if bipolar affective disorder or anxiety disorders pose a similar risk.
Aims
We aimed to compare the risk of LLADs progressing to all-cause dementia, and the demographic and clinical variables mediating the risk.
Methods
We used the South London and Maudsley National Health Service Foundation Trust Clinical Records Interactive Search system to identify patients aged 60 years or older with a diagnosis of any affective disorder. Cox proportional hazard models were used to determine differences in dementia risk between late-life anxiety disorders versus late-life depression, and late-life bipolar disorder versus late-life depression. Demographic and clinical characteristics associated with the risk of dementia were investigated.
Results
Some 5695 patients were identified and included in the final analysis. Of these, 388 had a diagnosis of bipolar affective disorder, 1365 had a diagnosis of an anxiety disorder and 3942 had a diagnosis of a depressive disorder. Bipolar affective disorder was associated with a lower hazard of developing dementia compared to depression (adjusted model including demographics and baseline cognition, hazard ratio: 0.60; 95% CI: 0.41–0.87). Anxiety disorders had a similar hazard of developing dementia (adjusted hazard ratio: 1.05; 95% CI: 0.90–1.22). A prior history of a depressive disorder reduced the risk of late-life depression progressing to dementia – suggesting the new onset of a depressive disorder in later life is associated with higher risk – but a prior history of anxiety disorders or bipolar affective disorder did not alter risk.
Conclusions
LLADs have a differential risk of developing all-cause dementia, with demographic- and illness-related factors influencing the risk. Further prospective cohort studies are needed to explore the link between LLADs and dementia development, and mediators of the lower risk of dementia associated with late-life bipolar disorder compared to late-life depression.
The governance of farm animal welfare is led, in certain countries and sectors, by industry organisations. The aim of this study was to analyse the legitimacy of industry-led farm animal welfare governance focusing on two examples: the Code of Practice for the Care and Handling of Dairy Cattle and the Animal Care module of the proAction programme in Canada, and the Animal Care module of the Farmers Assuring Responsible Management (FARM) programme in the United States (US). Both are dairy cattle welfare governance programmes led by industry actors who create the standards and audit farms for compliance. We described the normative legitimacy of these systems, based on an input, throughput, and output framework, by performing a document analysis on publicly available information from these organisations’ websites and found that the legitimacy of both systems was enhanced by their commitment to science, the presence of accountability systems to enforce standards, and wide participation by dairy farms. The Canadian system featured more balanced representation, and their standard development process uses a consensus-based model, which bolsters legitimacy compared to the US system. However, the US system was more transparent regarding audit outcomes than the Canadian system. Both systems face challenges to their legitimacy due to heavy industry representation and limited transparency as to how public feedback is addressed in the standards. These Canadian and US dairy industry standards illustrate strengths and weakness of industry-led farm animal welfare governance.
Introductions of new crops can provide alternate market opportunities, but also may pose ecological risks. New crops lack established management, have uncertain performance issues, and may become weedy in their introduced region. The introduction of hemp (Cannabis sativa L.) into southern Florida poses a unique introduction scenario because of the subtropical climate and no commercial production on record, unlike in other eastern and midwestern U.S. states. We assessed the escape from cultivation for hemp by tracking establishment and reproduction of volunteer plants from the earliest modern hemp planting in Florida. Hemp is a weed across much of the United States matching its historical distribution and has been assessed to be of high invasion risk for Florida because of its biological attributes, history of escape, and colonization in other states and countries. We conducted monitoring of volunteer plants and a seed establishment experiment in southern Florida finding that hemp volunteer plants occurred in pulses over time, with variable and declining germination. Volunteer plants persisted for up to 2 yr and appeared in areas that were disked and mowed according to USDA-approved hemp crop termination procedures. In the seed establishment experiment, we found that hemp established in disturbed soils (∼9% of seeds planted) and that mean plant heights and seed counts were positively related to soil disturbance and nutrient addition. These findings showed that hemp plantings should be monitored for volunteer establishment, and containment plans should be in place to control the establishment of volunteer hemp plants in agricultural fields. Our study further illustrates the need for multiyear monitoring and repeat termination procedures to ensure containment of hemp volunteers. There was limited evidence of volunteer establishment in surrounding areas and on undisturbed land. However, seed containment, equipment cleaning, and the monitoring of nearby fields and seed transportation routes remains warranted.
Using clean numerical simulation (CNS) in which artificial numerical noise is negligible over a finite, sufficiently long interval of time, we provide evidence, for the first time, that artificial numerical noise in direct numerical simulation (DNS) of turbulence is approximately equivalent to thermal fluctuation and/or stochastic environmental noise. This confers physical significance on the artificial numerical noise of DNS of the Navier–Stokes equations. As a result, DNS on a fine mesh should correspond to turbulence under small internal/external physical disturbance, whereas DNS on a sparse mesh corresponds to turbulent flow under large physical disturbance. The key point is that all of them have physical meanings and so are correct in terms of their deterministic physics, even if their statistics are quite different. This is illustrated herein. Our paper provides a positive viewpoint regarding the presence of artificial numerical noise in DNS.
Self-injurious behaviors (SIB) are common in autistic people. SIB is mainly studied as a broad category, rather than by specific SIB types. We aimed to determine associations of distinct SIB types with common psychiatric, emotional, medical, and socio-demographic factors.
Methods
Participants included 323 autistic youth (~50% non−/minimally-speaking) with high-confidence autism diagnoses ages 4–21 years. Data were collected by the Autism Inpatient Collection during admission to a specialized psychiatric inpatient unit (www.sfari.org/resource/autism-inpatient-collection/). Caregivers completed questionnaires about their child, including SIB type and severity. The youth completed assessments with clinicians. Elastic net regressions identified associations between SIB types and factors.
Results
No single factor relates to all SIB types. SIB types have unique sets of associations. Consistent with previous work, more repetitive motor movements and lower adaptive skills are associated with most types of SIB; female sex is associated with hair/skin pulling and self-rubbing/scratching. More attention-deficit/hyperactivity disorder symptoms are associated with self-rubbing/scratching, skin picking, hair/skin pulling, and inserts finger/object. Inserts finger/object has the most medical condition associations. Self-hitting against surface/object has the most emotion dysregulation associations.
Conclusions
Specific SIB types have unique sets of associations. Future work can develop clinical likelihood scores for specific SIB types in inpatient settings, which can be tested with large community samples. Current approaches for SIB focus on the behavior functions, but there is an opportunity to further develop interventions by considering the specific SIB type in assessment and treatment. Identifying factors associated with specific SIB types may aid with screening, prevention, and treatment of these often-impairing behaviors.
The changing climate, land use, and agronomic practices are driving shifts in weed biology and management across Australia’s grain production systems. A stakeholder survey was conducted to identify key weed species, adaptations, and factors influencing future research priorities in three major cropping regions. The most problematic and adaptive species included rigid ryegrass (Lolium rigidum Gaudin), hairy fleabane [Conyza bonariensis (L.) Cronquist; syn.: Erigeron bonariensis L.], Bromus spp. (ripgut brome [Bromus diandrus Roth; syn.: Bromus rigidus Roth]), annual sowthistle (Sonchus oleraceus L.), wild radish (Raphanus raphanistrum L.), and feather fingergrass (Chloris virgata Sw.). These weeds also ranked high for future research focus. Observed adaptive traits included changes in dormancy and emergence patterns, shifts in phenology, and a shift toward year-round growth driven by warmer winters and increased summer rainfall. Regional responses varied slightly, with soil and crop management practices ranked as the primary driver of changing weed biology (88%), followed by climatic factors (56%), while soil factors (13%) were not considered to be significant. Participants in the Northern region highlighted climate change (67%) as a major driver, while those in the Western region emphasized management practices (95%) and soil-related factors (32%). Sixty percent of participants noted that climatic changes were introducing new weeds, and 69% believed that changing weed biology was reducing control efficacy. National research priorities included understanding weed emergence dynamics (73%), effects of climate on herbicide efficacy (71%), and better understanding of weed ecology (68%). These findings highlight the trends in weed evolution and need for future research on changing weed biology and adaptive management strategies. Surveys of agronomists, farm advisors, researchers, and farmers provide a cost-effective method to monitor new weed adaptations. Refining survey methodologies and enhancing field data collection could improve the ability to track and manage weed adaptations to shifts in climate and management practices.
The aim of this policy article is twofold: (i) to provide a summary and update of recent important policy developments, in particular relevant guidance on the use of real-world data/real-world evidence (RWD/RWE) by health technology assessment (HTA) bodies and (ii) to set out our policy recommendations on how the different elements of an “RWE framework” we have previously developed could support, further enhance and facilitate the use of RWE for HTA purposes and by HTA bodies and payers.
Methods
We undertook a targeted review and analysis of recent important policy developments. The aim was to build on our recommendations from previous work on the “RWE Framework,” and consider how the relevant tools from our Framework can further enhance and facilitate the use of RWE for HTA purposes and by HTA bodies/payers.
Results
We provide eight conditions that we argue would, in combination, constitute the optimal use and acceptance of RWD/RWE for HTA. We believe that, should the eight conditions hold, RWD/RWE would enable more efficient access to medicines and healthcare technologies for patients.
Conclusions
High-quality, fit-for-purpose RWD/RWE can and should be used more frequently in HTA. Multi-stakeholder and cross-geography collaborative partnerships are needed to align on best practices to optimize the evidence that needs to be generated to satisfy all stakeholders’ needs.
During the COVID-19 pandemic, Chile enacted three exceptional laws allowing withdrawals from affiliates’ pension accounts. We analyze how these withdrawals affected pension savings and the projected retirement income of affiliates and their households, finding that lower-income households withdrew a higher percentage of their savings. Simulations of worker contributions until retirement show an average reduction of 21% in contributory pensions, but increased non-contributory pension benefits reduce the average total income loss to 8%. Under a no-reform scenario, these withdrawals and higher non-contributory pensions may imply fiscal costs around 15.8% of the pre-pandemic gross domestic product (GDP). The current pension reform should reduce it to 12.4% of pre-pandemic GDP.
Findings from contemporary clinical trials suggest that psychedelics are generally safe and may be effective in the treatment of various psychiatric disorders. However, less is known about the risks associated with psychedelic use outside of medically supervised contexts, particularly in populations that are typically excluded from participation in clinical trials.
Methods
Using a preregistered longitudinal observational research design with a purposive sample of US residents between 18 and 50 years old (N=21,990), we investigated associations between self-reported naturalistic psychedelic use and psychotic and manic symptoms, with emphasis on those with psychiatric histories of schizophrenia or bipolar I disorder.
Results
The follow-up survey was completed by 12,345 participants (56% retention), with 505 participants reporting psychedelic use during the 2-month study period. In covariate-adjusted regression models, psychedelic use during the study period was associated with increases in the severity of psychotic and manic symptoms. However, such increases were only observed for those who reported psychedelic use in an illegal context. While increases in the severity of psychotic symptoms appeared to depend on the frequency of use and the intensity of challenging psychedelic experiences, increases in the severity of manic symptoms appeared to be moderated by a personal history of schizophrenia or bipolar I disorder and the subjective experience of insight during a psychedelic experience.
Conclusions
The findings suggest that naturalistic psychedelic use specifically in illegal contexts may lead to increases in the severity of psychotic and manic symptoms. Such increases may depend on the frequency of use, the acute subjective psychedelic experience, and psychiatric history.
Consider, for any integer $n\ge 3$, the set $\operatorname {\mathrm {Pos}}_n$ of all n-periodic tree patterns with positive topological entropy and the set $\operatorname {\mathrm {Irr}}_n\subset \operatorname {\mathrm {Pos}}_n$ of all n-periodic irreducible tree patterns. The aim of this paper is to determine the elements of minimum entropy in the families $\operatorname {\mathrm {Pos}}_n$, $\operatorname {\mathrm {Irr}}_n$ and $\operatorname {\mathrm {Pos}}_n\setminus \operatorname {\mathrm {Irr}}_n$. Let $\unicode{x3bb} _n$ be the unique real root of the polynomial $x^n-2x-1$ in $(1,+\infty )$. We explicitly construct an irreducible n-periodic tree pattern $\mathcal {Q}_n$ whose entropy is $\log (\unicode{x3bb} _n)$. We prove that this entropy is minimum in $\operatorname {\mathrm {Pos}}_n$. Since the pattern $\mathcal {Q}_n$ is irreducible, $\mathcal {Q}_n$ also minimizes the entropy in the family $\operatorname {\mathrm {Irr}}_n$. We also prove that the minimum positive entropy in the set $\operatorname {\mathrm {Pos}}_n\setminus \operatorname {\mathrm {Irr}}_n$ (which is non-empty only for composite integers $n\ge 6$) is $\log (\unicode{x3bb} _{n/p})/p$, where p is the least prime factor of n.
The implementation of a polymerase chain reaction-based pneumonia panel was associated with actionable results in 87% of 384 cases. In a population of mostly elderly non-intensive care unit patients with sputum samples, opportunities for antibiotic stewardship included streamlining for atypical bacteria, Pseudomonas aeruginosa, and methicillin-resistant Staphylococcus aureus coverage, with occasional opportunities to escalate antibiotic therapy.
The primary objective of this study is to assess the workload situation within Iran’s primary healthcare (PHC) sector, with an emphasis on identifying workforce needs and ascertaining any existing shortages or surpluses.
Background:
Over the past four decades, the establishment of PHC in Iran has been a significant accomplishment for the country’s healthcare system. Iran places substantial importance on achieving universal health coverage through PHC, aligning with global health goals, and acknowledging the critical role of human resources in this context. This commitment has enabled widespread and inclusive access to PHC services for both urban and rural populations across the nation. The primary objective of this study is to assess the workload situation within Iran’s PHC sector, with an emphasis on identifying workforce needs and ascertaining any existing shortages or surpluses.
Methods:
In 2023, a retrospective cross-sectional survey in Iran’s PHC sector sampled 1,212 individuals from 557 units across seven districts. Units were selected based on predetermined criteria for proportional representation of eligible occupational groups. Data was collected using tailored electronic questionnaires, covering facility and individual characteristics, working time, activities, and support tasks. Shortages or surpluses were assessed using Workload Indicators of Staffing Need (WISN) ratios under various scenarios, utilizing data from 2022 registration systems. Adjusted time data-informed workload pressure calculations.
Findings:
Customizing the WISN protocol to each country’s context is crucial, involving stakeholders in study design, including sample selection and data collection methods. Contextual facility information aids analysis, necessitating standardized data collection approaches for diverse registration systems.
In this paper, we consider the defocusing nonlinear wave equation $-\partial _t^2u+\Delta u=|u|^{p-1}u$ in $\mathbb {R}\times \mathbb {R}^d$. Building on our companion work (Self-similar imploding solutions of the relativistic Euler equations, arXiv:2403.11471), we prove that for $d=4, p\geq 29$ and $d\geq 5, p\geq 17$, there exists a smooth complex-valued solution that blows up in finite time.
High-beta magnetised plasmas often exhibit anomalously structured temperature profiles, as seen from galaxy cluster observations and recent experiments. It is well known that when such plasmas are collisionless, temperature gradients along the magnetic field can excite whistler waves that efficiently scatter electrons to limit their heat transport. Only recently has it been shown that parallel temperature gradients can excite whistler waves also in collisional plasmas. Here, we develop a Wigner–Moyal theory for the collisional whistler instability starting from Braginskii-like fluid equations in a slab geometry. This formalism is necessary because, for a large region in parameter space, the fastest-growing whistler waves have wavelengths comparable to the background temperature gradients. We find additional damping terms in the expression for the instability growth rate involving inhomogeneous Nernst advection and resistivity. They (i) enable whistler waves to re-arrange the electron temperature profile via growth, propagation and subsequent dissipation, and (ii) allow non-constant temperature profiles to exist stably. For high-beta plasmas, the marginally stable solutions take the form of a temperature staircase along the magnetic field lines. The electron heat flux can also be suppressed by the Ettingshausen effect when the whistler intensity profile is sufficiently peaked and oriented opposite the background temperature gradient. This mechanism allows cold fronts without magnetic draping, might reduce parallel heat losses in inertial fusion experiments and generally demonstrates that whistler waves can regulate transport even in the collisional limit.
This article examines some characteristics and functions of multiplex tactics in small storytelling. It uses a case-study based on three long informal interviews with a participant from the Gauteng, South Africa. Analysis and discussion raise questions of conversational resources and involvement, and thereby of a critical understanding of creativity and cooperation in interactional doing being. Multiplex tactics produce effects on several levels of interactional and discursive organisation simultaneously: signalling participative and narrative framing, footing and stance, whilst also effecting story entry and exit, or providing coherence between storied elements, for example. Multiplexity is a resource for accessing intersubjective meaning-making and narrative co-construction. Furthermore, it contributes to the vast body of work on indexicality and discourse marking. The article focuses on the creative, affective, and evolutive nature of involvement in interactional work.