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Several filamentary discharges can be applied to a combustible mixture, which can then ignite. The energy density of this discharge is a vital parameter, as it directly influences the local temperature rise and radical production. The goal of this article is to investigate how a previous discharge affects the energy density of a second discharge. To investigate the pulse-to-pulse coupling of filamentary discharges a one-dimensional numerical model is developed. In the developed model, the compressible Navier-Stokes equations are coupled to a plasma model. The plasma model is used to estimate the local energy density, while the compressible Navier-Stokes equations model the reactive flow. As a first step, skeletal air plasma chemistry is used, which includes fast gas heating, slow gas heating and the rapid generation of radicals. The skeletal plasma chemistry is combined with a detailed hydrogen combustion mechanism. Simulations in both air and hydrogen/air are conducted at several discharge energies and pressures. From the analysis of these results, we conclude that the main mechanism of pulse-to-pulse coupling is the reduction in molar density due to temperature rise.

Purpose: We compared hemodynamic parameters between subjects with marked, intermediate and minimal cardioinhibition during vasovagal syncope.Methods: The study included subjects with a decrease in heart rate while experiencing a complete vasovagal syncope during tilt-table testing. The subjects were classified as having marked, intermediate or minimal cardioinhibition, based on tertile values of the decrease in heart rate. Hemodynamic parameters between these groups were compared before tilt in the supine position, shortly after tilt and during cardioinhibition. Results:A total of 149 subjects with a median age of 43 (interquartile range 24–60) years were included in the study. Among the three groups with different levels of cardioinhibition, the highest heart rate was observed in subjects with marked cardioinhibition both before and shortly after tilt and at the start of cardioinhibition. The heart rate decrease in these subjects was both larger and faster compared to subjects with minimal and intermediate cardioinhibition. Conclusion: Subjects with marked cardioinhibition have both a larger and faster decrease in heart rate compared to subjects with intermediate and minimal cardioinhibition, as early as from the start of cardioinhibition. Marked cardioinhibition is related to differences in hemodynamic profiles already present well before the start of cardioinhibition.

Sown field margins can improve the conservation of biodiversity in rural areas and can contribute to the aesthetics of rural landscapes, thereby potentially increasing public support for agri-environmental measures. However, these two functions do not necessarily coincide. This raises the question whether field margins that are appreciated for their contribution to landscape aesthetics also deliver on the conservation of biodiversity. We conducted choice experiments with different groups of citizens and collected biodiversity data in the Netherlands, to investigate if the number of colors and vegetation cover in field margins increased respondents’ appreciation for them, and how these visual cues correlated with taxonomic diversity and abundance of plants and invertebrates in those field margins. Using manipulated photos, we also assessed whether the presence of colorful field margins in a range of different rural landscapes increased respondents’ appreciation of those landscapes. Respondents preferred colorful margins with high vegetation cover and showed a preference for green rural landscapes with colorful field margins. The presence of colorful field margins increased landscape aesthetics most in the least appreciated landscapes. The number of colors correlated positively with the diversity of sown and spontaneous plant species, and overall invertebrate abundance and abundance of predatory invertebrates, but was not related to invertebrate diversity. Our results show for the first time that colorful field margins support both public appreciation and diversity of plants and abundance of ground-dwelling invertebrates, with potential advantages to farmers in terms of natural pest control, at least in intensively used agricultural landscapes. However, management practices to maintain a high number of colors over time may be detrimental for invertebrate diversity. To optimize the different functions, we recommend that field margin layouts should consist of a perennia

Science plays a crucial role in identifying transformative change trajectories that are positive for biodiversity and human well-being. The concept of transformative change for biodiversity is receiving increased attention both within the political as well as in the scientific arena, but what transformative change entails still remains scientifically unclear. In this paper we report on a research priority exercise undertaken at the 2022 Alternet conference in which conference participants within each session were asked to jointly propose research gaps relevant to transformative change. Thirteen research priorities are identified, emphasising the need to learn from doing through transdisciplinary participatory action research, involving multiple disciplines including social sciences and building on existing research on, for example, nature-based solutions, OneHealth and climate change. The identified research priorities were later analysed under the umbrella of transformative change principles as a proxy for science to act as a lever to realise transformative change for biodiversity. Mobilising scientific research, interdisciplinarity and co-construction with stakeholders and decision-makers is a necessary step forward to make transformative progress in developing the biodiversity research agenda. In this respect, transformative action by the scientific community to develop the research agenda in an all-inclusive participatory process can be seen as a lever of transformative change for biodiversity. Such an all-inclusive participatory process for the development of a long-term biodiversity research agenda is in accordance with building on an integrated and whole-of-society approach as included in the EU Biodiversity Strategy’s aims and priorities around enabling transformative change.

The injection of electron cyclotron (EC) waves fulfills a number of important tasks in nuclear fusion devices for which detailed knowledge of the spatial power deposition profile is critical. This deposition profile is commonly determined using forward models such as beam or ray tracing. Recent numerical and experimental studies have shown that small-angle scattering of the EC beam as it passes through the turbulent plasma edge can cause significant broadening of the effective deposition profile, leading to considerable underestimation of the deposition width by forward methods. However, traditional inverse methods to determine the deposition profile from measurements overestimate the deposition profile width due to transport broadening. In this work, we implement three novel methods to resolve the EC power deposition profile from measurements that counteract transport broadening by simultaneously resolving transport and power deposition. We validate their assumptions and compare the results from these methods to the traditional break-in-slope method as well as to the TORAY ray-tracing code in a set of DIII-D discharges spanning five different confinement modes. We show that the four different inverse methods, novel and established, paint a consistent picture of deposition broadening. Specifically, we show that the measured power deposition profile is between 1.6 and 3.6 times wider than the TORAY profiles. Moreover, we show the considerable consequences that this level of broadening can have for ITER.

BACKGROUND Short-term neck pain after posterior cervical foraminotomy (posterior surgery) compared with anterior cervical discectomy with fusion (anterior surgery) treating cervical radiculopathy has only been assessed once, retrospectively, to our knowledge. The aim of this study was to prospectively evaluate the course of neck pain for 6 weeks after both treatments. METHODS This is a secondary analysis of the multicenter Foraminotomy ACDF Cost-Effectiveness Trial (FACET), conducted from January 2016 to May 2020. Of 389 patients who had single-level, 1-sided cervical radiculopathy and were screened for eligibility, 265 were randomly assigned to undergo posterior surgery (n = 132) or anterior surgery (n = 133). The primary outcome of the present analysis was neck pain, assessed weekly for 6 weeks using the visual analog scale (VAS), on a scale of 0 to 100. The secondary outcomes were arm pain, neck disability, work ability, quality of life, treatment satisfaction, motor and sensory changes, and hospital length of stay. Data were analyzed with mixed model analysis in intention-to-treat samples using 2-sided 95% confidence intervals (CIs). RESULTS In the first postoperative week, the mean VAS for neck pain was 56.2 mm (95% CI, 51.7 to 60.8 mm) after posterior surgery and 46.7 mm (95% CI, 42.2 to 51.2 mm) after anterior surgery. The mean between-group difference was 9.5 mm (95% CI, 3.3 to 15.7 mm), which gradually decreased to 2.3 mm (95% CI, -3.6 to 8.1 mm) at postoperative week 6. As of postoperative week 5, there was no significant difference between groups. Responder analyses confirmed this result. Secondary outcomes showed small differences between groups. CONCLUSIONS Insight into the course of neck pain during the first 6 weeks after posterior compared with anterior surgery is provided. Despite initially more neck pain after posterior surgery, patients swiftly improved and, as of postoperative week 5, results similar to those after anterior surgery were observed.