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Harvest weed seed control (HWSC) is a weed management technique that intercepts and destroys weed seeds before they replenish the soil weed seedbank and can be used to control herbicide-resistant weeds in global cropping systems. Wild radish (Raphanus raphanistrum L.) is a problematic, globally distributed weed species that is considered highly susceptible to HWSC as it retains much of its seed on the plant during grain harvest. However, previous studies have demonstrated that R. raphanistrum is capable of adapting its life cycle, in particular flowering time; to allow individuals more time to mature and potentially shed seeds before harvest, thereby evading HWSC interception. This study compared the vegetative growth plus physiological and ecological fitness of an early flowering R. raphanistrum biotype with an unselected genetically related biotype to determine if physiological costs of early flowering exist, when in competition with wheat (Triticum aestivum L.). Early flowering time adaptation in R. raphanistrum did not change the relative growth rate or competitive ability of R. raphanistrum. However, the height of first flower was reduced in the early flowering time-selected population, indicating that this population would retain more pods below the typical harvest cutting height (15 cm) used in HWSC. The presence of wheat competition (160 – 200 plants m-2) increased flowering height in the early flowering time-selected population, which would likely increase the susceptibility of early flowering R. raphanistrum plants to HWSC. Overall, early-flowering adaption in R. raphanistrum is a possible strategy to escape being captured by the HWSC; however, increasing crop competition is likely to be an effective strategy to maintain the effectiveness of HWSC.
The finite-amplitude space–time mean flows that are precessionally forced in rotating finite circular cylinders are examined. The findings show that, in addition to conventional Reynolds-stress-type source terms for streaming in oscillatory forced flows, a set of Coriolis-type source terms due the background rotation also contribute. These terms result from the interaction between the equatorial component of the total rotation vector and the overturning flow that is forced by the precession, both of which have azimuthal wavenumbers $m={\pm }1$. The interaction is particular to precessing flows and does not exist in rotating flows driven by libration ($m=0$ forcing) or tides ($m={\pm }2$ forcing). By examining typical example flows in the quasi-linear weakly forced streaming regime, we are able to consider the contributions from the Reynolds-stress terms and the equatorial-Coriolis terms separately, and find that they are of similar magnitude. In the cases examined, the azimuthal component of streaming flow driven by the equatorial-Coriolis terms is everywhere retrograde, whereas that driven by Reynolds stresses may have both retrograde and prograde regions, but the total streaming flows are everywhere retrograde. Even when the forcing frequency is larger than twice the background rotation rate, we find that there is a streaming flow driven by both the Reynolds-stress and the equatorial-Coriolis terms. For cases forced at precession frequencies in near resonance with the eigenfrequencies of the intrinsic inertial modes of the linear inviscid unforced rotating cylinder flow, we quantify theoretically how the amplitude of streaming flow scales with respect to variations in Reynolds number, cylinder tilt angle and aspect ratio, and compare these with numerical simulations.
In order to maximize the utility of future studies of trilobite ontogeny, we propose a set of standard practices that relate to the collection, nomenclature, description, depiction, and interpretation of ontogenetic series inferred from articulated specimens belonging to individual species. In some cases, these suggestions may also apply to ontogenetic studies of other fossilized taxa.
The SPARC tokamak is a critical next step towards commercial fusion energy. SPARC is designed as a high-field ($B_0 = 12.2$ T), compact ($R_0 = 1.85$ m, $a = 0.57$ m), superconducting, D-T tokamak with the goal of producing fusion gain $Q>2$ from a magnetically confined fusion plasma for the first time. Currently under design, SPARC will continue the high-field path of the Alcator series of tokamaks, utilizing new magnets based on rare earth barium copper oxide high-temperature superconductors to achieve high performance in a compact device. The goal of $Q>2$ is achievable with conservative physics assumptions ($H_{98,y2} = 0.7$) and, with the nominal assumption of $H_{98,y2} = 1$, SPARC is projected to attain $Q \approx 11$ and $P_{\textrm {fusion}} \approx 140$ MW. SPARC will therefore constitute a unique platform for burning plasma physics research with high density ($\langle n_{e} \rangle \approx 3 \times 10^{20}\ \textrm {m}^{-3}$), high temperature ($\langle T_e \rangle \approx 7$ keV) and high power density ($P_{\textrm {fusion}}/V_{\textrm {plasma}} \approx 7\ \textrm {MW}\,\textrm {m}^{-3}$) relevant to fusion power plants. SPARC's place in the path to commercial fusion energy, its parameters and the current status of SPARC design work are presented. This work also describes the basis for global performance projections and summarizes some of the physics analysis that is presented in greater detail in the companion articles of this collection.
Owing to its high magnetic field, high power, and compact size, the SPARC experiment will operate with divertor conditions at or above those expected in reactor-class tokamaks. Power exhaust at this scale remains one of the key challenges for practical fusion energy. Based on empirical scalings, the peak unmitigated divertor parallel heat flux is projected to be greater than 10 GW m−2. This is nearly an order of magnitude higher than has been demonstrated to date. Furthermore, the divertor parallel Edge-Localized Mode (ELM) energy fluence projections (~11–34 MJ m−2) are comparable with those for ITER. However, the relatively short pulse length (~25 s pulse, with a ~10 s flat top) provides the opportunity to consider mitigation schemes unsuited to long-pulse devices including ITER and reactors. The baseline scenario for SPARC employs a ~1 Hz strike point sweep to spread the heat flux over a large divertor target surface area to keep tile surface temperatures within tolerable levels without the use of active divertor cooling systems. In addition, SPARC operation presents a unique opportunity to study divertor heat exhaust mitigation at reactor-level plasma densities and power fluxes. Not only will SPARC test the limits of current experimental scalings and serve for benchmarking theoretical models in reactor regimes, it is also being designed to enable the assessment of long-legged and X-point target advanced divertor magnetic configurations. Experimental results from SPARC will be crucial to reducing risk for a fusion pilot plant divertor design.
In order to inform core performance projections and divertor design, the baseline SPARC tokamak plasma discharge is evaluated for its expected H-mode access, pedestal pressure and edge-localized mode (ELM) characteristics. A clear window for H-mode access is predicted for full field DT plasmas, with the available 25 MW of design auxiliary power. Additional alpha heating is likely needed for H-mode sustainment. Pressure pedestal predictions in the developed H-mode are surveyed using the EPED model. The projected SPARC pedestal would be limited dominantly by peeling modes and may achieve pressures in excess of 0.3 MPa at a density of approximately 3 × 1020 m−3. High pedestal pressure is partially enabled by strong equilibrium shaping, which has been increased as part of recent design iterations. Edge-localized modes (ELMs) with >1 MJ of energy are projected, and approaches for reducing the ELM size, and thus the peak energy fluence to divertor surfaces, are under consideration. The high pedestal predicted for SPARC provides ample margin to satisfy its high fusion gain (Q) mission, so that even if ELM mitigation techniques result in a 2× reduction of the pedestal pressure, Q > 2 is still predicted.
SPARC is designed to be a high-field, medium-size tokamak aimed at achieving net energy gain with ion cyclotron range-of-frequencies (ICRF) as its primary auxiliary heating mechanism. Empirical predictions with conservative physics indicate that SPARC baseline plasmas would reach $Q\approx 11$, which is well above its mission objective of $Q>2$. To build confidence that SPARC will be successful, physics-based integrated modelling has also been performed. The TRANSP code coupled with the theory-based trapped gyro-Landau fluid (TGLF) turbulence model and EPED predictions for pedestal stability find that $Q\approx 9$ is attainable in standard H-mode operation and confirms $Q > 2$ operation is feasible even with adverse assumptions. In this analysis, ion cyclotron waves are simulated with the full wave TORIC code and alpha heating is modelled with the Monte–Carlo fast ion NUBEAM module. Detailed analysis of expected turbulence regimes with linear and nonlinear CGYRO simulations is also presented, demonstrating that profile predictions with the TGLF reduced model are in reasonable agreement.
Prehospital intramuscular (IM) ketamine is increasingly used for chemical restraint of agitated patients. However, few studies have assessed emergency department (ED) follow-up of patients receiving prehospital ketamine for this indication, with previous reports suggesting a high rate of post-administration intubation. This study examines the rate of and reasons for intubation and other airway interventions in agitated patients who received ketamine by Emergency Medical Services (EMS).
Methods:
This retrospective cohort study included patients who received prehospital ketamine for agitation and were transported to two community hospital EDs. Charts were reviewed for demographics, ketamine dose, and airway intervention by EMS or in the ED. Characteristics of patients who were intubated versus those who did not receive airway intervention were analyzed.
Results:
Over 28 months, 86 patients received ketamine for agitation. Fourteen (16.3%) underwent endotracheal intubation. Patients with a higher temperature and a lower Glasgow Coma Score (GCS) were more likely to require intubation. There was no age or dose-dependent association on intubation rate. Intubated patients averaged 39 years old versus 44 for patients not intubated (negative five-year difference; 95% CI, -16 to 6). The mean ketamine dose was 339.3mg in patients intubated versus 350.7mg in patients not (-11.4mg difference; 95% CI, -72.4 to 49.6). The mean weight-based ketamine dose was 4.44mg/kg in patients intubated versus 4.96mg/kg in patients not (-0.53mg/kg difference; 95% CI, -1.49 to 0.43).
Conclusions:
The observed rate of intubation in patients receiving prehospital ketamine for agitation was 16.3%. Study data did not reveal an age or dose-dependent rate of intubation. Further research should be conducted to compare the airway intervention rate of agitated patients receiving ketamine versus other sedatives in a controlled fashion.
Few studies have examined burnout in psychosocial oncology clinicians. The aim of this systematic review was to summarize what is known about the prevalence and severity of burnout in psychosocial clinicians who work in oncology settings and the factors that are believed to contribute or protect against it.
Method
Articles on burnout (including compassion fatigue and secondary trauma) in psychosocial oncology clinicians were identified by searching PubMed/MEDLINE, EMBASE, PsycINFO, the Cumulative Index to Nursing and Allied Health Literature, and the Web of Science Core Collection.
Results
Thirty-eight articles were reviewed at the full-text level, and of those, nine met study inclusion criteria. All were published between 2004 and 2018 and included data from 678 psychosocial clinicians. Quality assessment revealed relatively low risk of bias and high methodological quality. Study composition and sample size varied greatly, and the majority of clinicians were aged between 40 and 59 years. Across studies, 10 different measures were used to assess burnout, secondary traumatic stress, and compassion fatigue, in addition to factors that might impact burnout, including work engagement, meaning, and moral distress. When compared with other medical professionals, psychosocial oncology clinicians endorsed lower levels of burnout.
Significance of results
This systematic review suggests that psychosocial clinicians are not at increased risk of burnout compared with other health care professionals working in oncology or in mental health. Although the data are quite limited, several factors appear to be associated with less burnout in psychosocial clinicians, including exposure to patient recovery, discussing traumas, less moral distress, and finding meaning in their work. More research using standardized measures of burnout with larger samples of clinicians is needed to examine both prevalence rates and how the experience of burnout changes over time. By virtue of their training, psychosocial clinicians are well placed to support each other and their nursing and medical colleagues.
Pollen-mediated gene flow (PMGF) refers to the transfer of genetic information (alleles) from one plant to another compatible plant. With the evolution of herbicide-resistant (HR) weeds, PMGF plays an important role in the transfer of resistance alleles from HR to susceptible weeds; however, little attention is given to this topic. The objective of this work was to review reproductive biology, PMGF studies, and interspecific hybridization, as well as potential for herbicide resistance alleles to transfer in the economically important broadleaf weeds including common lambsquarters, giant ragweed, horseweed, kochia, Palmer amaranth, and waterhemp. The PMGF studies involving these species reveal that transfer of herbicide resistance alleles routinely occurs under field conditions and is influenced by several factors, such as reproductive biology, environment, and production practices. Interspecific hybridization studies within Amaranthus and Ambrosia spp. show that herbicide resistance allele transfer is possible between species of the same genus but at relatively low levels. The widespread occurrence of HR weed populations and high genetic diversity is at least partly due to PMGF, particularly in dioecious species such as Palmer amaranth and waterhemp compared with monoecious species such as common lambsquarters and horseweed. Prolific pollen production in giant ragweed contributes to PMGF. Kochia, a wind-pollinated species can efficiently disseminate herbicide resistance alleles via both PMGF and tumbleweed seed dispersal, resulting in widespread occurrence of multiple HR kochia populations. The findings from this review verify that intra- and interspecific gene flow can occur and, even at a low rate, could contribute to the rapid spread of herbicide resistance alleles. More research is needed to determine the role of PMGF in transferring multiple herbicide resistance alleles at the landscape level.
The Spoon-billed Sandpiper Calidris pygmaea is a ‘Critically Endangered’ migratory shorebird. The species faces an array of threats in its non-breeding range, making conservation intervention essential. However, conservation efforts are reliant on identifying the species’ key stopover and wintering sites. Using Maximum Entropy models, we predicted Spoon-billed Sandpiper distribution across the non-breeding range, using data from recent field surveys and satellite tracking. Model outputs suggest only a limited number of stopover sites are suitable for migrating birds, with sites in the Yellow Sea and on the Jiangsu coast in China highlighted as particularly important. All the previously known core wintering sites were identified by the model including the Ganges-Brahmaputra Delta, Nan Thar Island and the Gulf of Mottama. In addition, the model highlighted sites subsequently found to be occupied, and pinpointed potential new sites meriting investigation, notably on Borneo and Sulawesi, and in parts of India and the Philippines. A comparison between the areas identified as most likely to be occupied and protected areas showed that very few locations are covered by conservation designations. Known sites must be managed for conservation as a priority, and potential new sites should be surveyed as soon as is feasible to assess occupancy status. Site protection should take place in concert with conservation interventions including habitat management, discouraging hunting, and fostering alternative livelihoods.
We report key learning from the public health management of the first two confirmed cases of COVID-19 identified in the UK. The first case imported, and the second associated with probable person-to-person transmission within the UK. Contact tracing was complex and fast-moving. Potential exposures for both cases were reviewed, and 52 contacts were identified. No further confirmed COVID-19 cases have been linked epidemiologically to these two cases. As steps are made to enhance contact tracing across the UK, the lessons learned from earlier contact tracing during the country's containment phase are particularly important and timely.
The Clinical and Translational Science Awards (CTSA) Consortium, about 60 National Institutes of Health (NIH)-supported CTSA hubs at academic health care institutions nationwide, is charged with improving the clinical and translational research enterprise. Together with the NIH National Center for Advancing Translational Sciences (NCATS), the Consortium implemented Common Metrics and a shared performance improvement framework.
Methods:
Initial implementation across hubs was assessed using quantitative and qualitative methods over a 19-month period. The primary outcome was implementation of three Common Metrics and the performance improvement framework. Challenges and facilitators were elicited.
Results:
Among 59 hubs with data, all began implementing Common Metrics, but about one-third had completed all activities for three metrics within the study period. The vast majority of hubs computed metric results and undertook activities to understand performance. Differences in completion appeared in developing and carrying out performance improvement plans. Seven key factors affected progress: hub size and resources, hub prior experience with performance management, alignment of local context with needs of the Common Metrics implementation, hub authority in the local institutional structure, hub engagement (including CTSA Principal Investigator involvement), stakeholder engagement, and attending training and coaching.
Conclusions:
Implementing Common Metrics and performance improvement in a large network of research-focused organizations proved feasible but required substantial time and resources. Considerable heterogeneity across hubs in data systems, existing processes and personnel, organizational structures, and local priorities of home institutions created disparate experiences across hubs. Future metric-based performance management initiatives across heterogeneous local contexts should anticipate and account for these types of differences.
Youth mental health is a rapidly developing field with a focus on prevention, early identification, treatment innovation and service development. In this perspective piece, we discuss the effects of COVID-19 on young people’s mental health. The psychosocial effects of COVID-19 disproportionately affect young people. Both immediate and longer-term factors through which young people are affected include social isolation, changes to the delivery of therapeutic services and almost complete loss of all structured occupations (school, work and training) within this population group. Longer-term mechanisms include the effects of the predicted recession on young people’s mental health. Opportunities within this crisis exist for service providers to scale up telehealth and digital services that may benefit service provision for young people’s mental health in the future.
There is an increasing tendency for reasonably large heterogeneous data sets to be released digitally online as part of public inquiries or court cases. These data sets may be composed of PDF files, images and scanned handwritten documents; some voluntarily and intentionally released, others released only after requests or via leaks. The release of these data sets is often justified as necessary to improve the transparency of a process or the operations of an organisation. When the data is released willingly, the intention may be that the released evidence would support the conclusions of the investigation or inquiry, thereby reinforcing the legitimacy of the process. Where the release of documents is only in response to successful external requests for evidence, such as via a state's Freedom of Information process (FOI), the release is often part of an attempt to make the decision-making process more transparent to the public by third parties (such as researchers or journalists). When data is leaked, it is the leaker or whistle-blower who might be attempting to inform the public about a process or practice that they believe should be known. In many of these situations questions remain as to how useful the released data actually is, the politics of how accessible it is, and what the politics are behind its relative accessibility?
This chapter looks at two case studies to highlight some aspects of these issues. It argues that the tools normally associated with the analysis of much larger big data sets can be successfully applied to improve the accessibility of inquiries and similar processes. The two cases that we draw on are the court-martial of Private Chelsea Manning in the US (Burgess 2012), and the Leveson Inquiry into the Culture, Practice and Ethics of the Press (Leveson Report) in the UK (Inquiry et al. 2012). We briefly also touch upon the materials that Manning leaked from US Army databases to WikiLeaks that lead to her court-martial.
The Manning trial of 2013 provides an example of a process whereby the supporting evidence, in the form of court exhibits and records, was released largely via a systematic process of FOI requests filed by a small number of individuals.
An Al–Cu–Li aerospace alloy has been investigated to determine the order in which corrosion at different types of sites occurs in AA2099-T83. Specifically, the sequence of galvanic attack on intermetallic (IM) particles and other sites of AA2099-T83 was determined as a function of time, in 0.1 M NaCl, through the use of scanning electron microscopy and electron backscatter diffraction characterization techniques. The earliest attack occurred at isolated grains and grain boundaries and on Li-containing dispersoids. Similarly, some constituent IM particles showed evidence of trenching in the surrounding alloy matrix. These IM particles included Al7Cu2Fe and another group of unidentified particles which displayed complete trenching within the first 10 min of exposure. Al13(Fe, Mn)4 were next most active followed by Al37Fe12Cu2 with Al6(Fe,Mn) and large TiB2 particles being the least active.
Spinal muscular atrophy (SMA) is a devastating rare disease that affects individuals regardless of ethnicity, gender, and age. The first-approved disease-modifying therapy for SMA, nusinursen, was approved by Health Canada, as well as by American and European regulatory agencies following positive clinical trial outcomes. The trials were conducted in a narrow pediatric population defined by age, severity, and genotype. Broad approval of therapy necessitates close follow-up of potential rare adverse events and effectiveness in the larger real-world population.
Methods:
The Canadian Neuromuscular Disease Registry (CNDR) undertook an iterative multi-stakeholder process to expand the existing SMA dataset to capture items relevant to patient outcomes in a post-marketing environment. The CNDR SMA expanded registry is a longitudinal, prospective, observational study of patients with SMA in Canada designed to evaluate the safety and effectiveness of novel therapies and provide practical information unattainable in trials.
Results:
The consensus expanded dataset includes items that address therapy effectiveness and safety and is collected in a multicenter, prospective, observational study, including SMA patients regardless of therapeutic status. The expanded dataset is aligned with global datasets to facilitate collaboration. Additionally, consensus dataset development aimed to standardize appropriate outcome measures across the network and broader Canadian community. Prospective outcome studies, data use, and analyses are independent of the funding partner.
Conclusion:
Prospective outcome data collected will provide results on safety and effectiveness in a post-therapy approval era. These data are essential to inform improvements in care and access to therapy for all SMA patients.
The Centers for Disease Control and Prevention (CDC), Division of State and Local Readiness (DSLR), Public Health Emergency Preparedness(PHEP) program funds 62 recipients to strengthen capability standards to prepare for and respond to public health emergencies. Recipients use these PHEP resources in addition to CDC’s administrative and scientific guidance to support preparedness and response program planning and requirements. It is expected that public health agencies develop and maintain comprehensive emergency preparedness and response plans in preparation for disasters such as hurricanes. The 2017 historic hurricane season highlighted how emergency planning and collaborative operational execution is important for public health agencies to effectively prepare for and respond to both the immediate and long-term population health consequences of these disasters. In 2017, the southeastern United States (US) and US Caribbean territories experienced 3 Category 4 or higher Atlantic hurricanes (Harvey, Irma, and Maria) within a 5-week period. This paper highlights selected case studies that illustrate the contributions and impact of jurisdictional emergency management planning and operational capacity supported by capability standards during the 2017 hurricane season. Although the magnitude of the 2017 hurricanes required public health officials to seek additional assistance, the following case studies describe the use of public health preparedness systems and recovery resources supported by the PHEP program.