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The need for geoscience students to develop a quantitative skillset is ever increasing. However, this can be difficult to implement in university-style lecture courses in a way that is both manageable for the instructor and does not involve lengthy, potentially repetitive, question sheets for the students. Here, a method for teaching dimensional analysis, basic fluid dynamics, and the interpretation and scaling of experimental data is presented for a graduate student audience. The proposed method utilizes simple fluid dynamic benchtop experiments that require a small amount of teaching space and use readily available, low cost materials. Our analysis of student performance through pre- and post-tests demonstrates that students have a better knowledge of dimensional analysis, data interpretation and experimental design after the series of practical sessions compared to instruction through a single, passive lecture. We therefore show that simple benchtop experiments can be an effective way to improve and integrate quantitative learning into a graduate geoscience class.

ObjectivesTo report the results of the Nit-Occlud PDA prospective postapproval study (PAS) along with a comparison to the results of the pivotal and continued access trials.BackgroundThe Nit-Occlud PDA (PFM Medical, Cologne, Germany), a nitinol coil patent ductus arteriosus (PDA) occluder, was approved by the Food and Drug Administration in 2013.MethodsThe PAS enrolled a total of 184 subjects greater than 6 months of age, weighing at least 5 kg, with PDAs less than 4 mm by angiography at 11 centers. Patients were followed prospectively at 2 months, 12 months, and 24 months postprocedure. These outcomes were compared to the 357 subjects enrolled in the pivotal and continued access protocols. Efficacy and safety data were reported.ResultsAmong 184 subjects enrolled for the PAS between 2014 and 2017, 180 (97.8%) had successful device implantation. After 12 months, 98.7% (150/152) had trivial or no residual shunt by echocardiography and two subjects had only small residual shunts. There were three device embolizations that were all retrieved by snare without clinical consequence. Together with the pivotal and continued access study, 97.4% (449/461) had complete echocardiographic closure at 12 months in 541 enrolled subjects. The composite success was 94.4%. There were no mortalities and no serious device-related adverse events.ConclusionsThe Nit-Occlud PDA is a safe and effective device for closure of a small to moderate sized PDA. There were no serious device-related adverse events in a large cohort of three clinical trials.

Owing to the rapid and robust clinical effects, electroconvulsive therapy (ECT) represents an optimal model to develop and test treatment predictors for major depressive disorders (MDDs), whereas imaging markers can be informative in identifying MDD patients who will respond to a specific antidepressant treatment or not. Here we aim to predict post-ECT depressive rating changes and remission status using pre-ECT gray matter (GM) in 38 MDD patients and validate in two independent data sets. Six GM regions including the right hippocampus/parahippocampus, right orbitofrontal gyrus, right inferior temporal gyrus (ITG), left postcentral gyrus/precuneus, left supplementary motor area, and left lingual gyrus were identified as predictors of ECT response, achieving accuracy of 89, 90 and 86% for remission prediction in three independent, age-matched data sets, respectively. For MDD patients, GM density increases only in the left supplementary motor cortex and left postcentral gyrus/precuneus after ECT. These results suggest that treatment-predictive and treatment-responsive regions may be anatomically different but functionally related in the context of ECT response. To the best of our knowledge, this is the first attempt to quantitatively identify and validate the ECT treatment biomarkers using multi-site GM data. We address a major clinical challenge and provide potential opportunities for more effective and timely interventions for electroconvulsive treatment.

Purpose: To determine whether competitive performance, as defined by International Biathlon Union (IBU) and International Ski Federation (FIS) points in biathlon and cross-country (XC) skiing, respectively, can be projected using a combination of anthropometric and physiological metrics. Shooting accuracy was also included in the biathlon models. Methods: Data were analyzed using multivariate methods from 45 (23 female and 22 male) biathletes and 202 (86 female and 116 male) XC skiers who were all members of senior national teams, national development teams, or ski-university or high school invite-only programs (age range: 16–36 y). Anthropometric and physiological characteristics were assessed via dual-energy X-ray absorptiometry and incremental roller-ski treadmill tests, respectively. Shooting accuracy was assessed via an outdoor standardized testing protocol. Results: Valid projective models were identified for female biathletes' IBU points (R2 =.80/Q2 =.65) and female XC skiers' FIS distance (R2 =.81/Q2 =.74) and sprint (R2 =.81/Q2 =.70) points. No valid models were identified for the men. The most important variables for the projection of IBU points were shooting accuracy, speeds at blood lactate concentrations of 4 and 2 mmol·L−1, peak aerobic power, and lean mass. The most important variables for the projection of FIS distance and sprint points were speeds at blood lactate concentrations of 4 and 2 mmol·L−1 and peak aerobic power. Conclusions: This study highlights the relative importance of specific anthropometric, physiological, and shooting-accuracy metrics in female biathletes and XC skiers. The data can help to identify the specific metrics that should be targeted when monitoring athletes' progression and designing training plans. [ABSTRACT FROM AUTHOR]

The demand for transparency about the microeconomic sources of environmental pollution has surged recently, causing carbon disclosure to rise to the top of the global climate change discourse. In this study, we empirically investigate how the environmental performance of firm production technologies shapes their voluntary carbon disclosure behaviour and how key stakeholders influence the performance‐disclosure relationship. Using a panel of 1,547 firms across 24 countries covering 2006–20, we find that firms with the most efficient technologies for reducing emissions tend to disclose their carbon impact, especially when they face more stringent environmental regulations. These high‐performing firms demonstrate a tendency for non‐disclosure when faced with intense shareholder and environmental activist pushback against pollution. Our findings also highlight the existence of a profitability penalty for transparent high‐efficiency firms relative to comparable firms that adopt strategic silence. [ABSTRACT FROM AUTHOR]

To infer adaptation of plant material, restoration practitioners often consider only surrogate geographic or climatic information. However, empirical biomass data could assist in deciding what material to use where. To test this approach, we transplanted seven bluebunch wheatgrass (BBWG; Pseudoroegneria spicata) and five Snake River wheatgrass (SRWG; Elymus wawawaiensis) populations to three sites ranging from low to high precipitation (LPPT, MPPT, and HPPT). We measured establishment‐year (2011) biomass at all sites and 2012–16 biomass at MPPT and HPPT. When data were standardized by site, P‐7 and Anatone produced the most BBWG biomass across sites and Wahluke the least in both 2011 and 2012–16, while E‐58X produced the most SRWG biomass and Secar and E‐49X the least in 2011 and 2012–16, respectively. Among BBWG populations in 2011, relative performance of P‐7 (G6 generation) and Goldar increased and Whitmar decreased at wetter sites, while Columbia was stable (high) and Wahluke was stable (low) over sites. Among SRWG populations in 2011, Secar, Secar78, and E‐58X increased at drier sites and Discovery at wetter sites. However, once established, populations of both species were much more similar for trend. In 2012–16, trend somewhat increased for five BBWG populations from MPPT to HPPT, was stable for Wahluke, but declined for Columbia, while all five SRWG populations declined at HPPT. These results suggest that, once established, BBWG is mostly stable across sites, while SRWG is less adapted to wetter sites. In 2012–16, BBWG populations originating at drier (or wetter) sites mostly performed relatively better at MPPT (or HPPT), suggesting adaptation to site. However, in the establishment year (2011), this relationship did not hold, suggesting seedling vigor and immature growth rate play a stronger role than precipitation at the site of origin. [ABSTRACT FROM AUTHOR]

Magma fragmentation is an essential process driving explosive volcanic eruptions, generating a distribution of pyroclasts with characteristic shape and grain size. These characteristics are often used to inform on the energetics of magma fragmentation and the associated eruption style and intensity. However, a portion of these pyroclasts, droplets when still in the molten state, are likely to be generated through impact mechanisms (i.e., collisions), and subsequent secondary fragmentation (i.e., splashing). Here, we successfully apply and dynamically scale concepts and findings of liquid droplet impacts in engineering to magma fragmentation processes in volcanology. We compile and model physical data for two mafic melt compositions (kimberlite and basalt) and use specific eruption examples from Igwisi Hills, Kīlauea and Stromboli volcanoes to define composition‐specific impact dynamics. Pyroclast impact dynamics have a direct control on in‐conduit processes, eruption dynamics, and ash dispersal. For low viscosity mafic melts such as kimberlite and basalt, pyroclast impacts can lead to both splash and deposition on the conduit wall, resulting either in conduit clearing or conduit narrowing, respectively. In both cases, shifting the impact regime toward surface deposition will lead to an inexorable decay in explosiveness, potentially switching the eruption style to effusive behavior. This has direct consequences for the transport of volcanic ash at the surface and inferring magma fragmentation processes (e.g., energies) from the depositional record. Plain Language Summary: During explosive eruptions, magma is ripped apart to form a distribution of incandescent fragments, termed pyroclasts, of different sizes and shapes. These characteristics are often used to forensically reconstruct eruption dynamics. For explosive volcanic eruptions of low viscosity magmas, fragmentation dynamics often resemble water spraying with the generation of droplets. In volcanoes, and under certain conditions, magma droplets can impact a surface or each other and further fragment, splashing into finer droplets. Such liquid impact dynamics have been long researched in engineering but seldom considered in volcanology. Here, we apply and scale the concepts of liquid impacts from engineering to volcanic processes. We compiled data for ultramafic and mafic magma compositions, which are characterized by different physical properties that influence the impact outcomes (e.g., splash vs. surface deposition). Droplet impacts may lead to splashing or sticking against the conduit wall. For example, under prolonged deposition conditions, progressive narrowing of the conduit could lead to eruption termination or switch to pure lava effusion. Finally, we show that droplet impacts are likely to control the final size of pyroclasts produced during ultramafic and mafic explosive eruptions, and therefore must be considered when interpreting the rock record from related past events. Key Points: Liquid droplet impacts are relevant to magma fragmentation processes in volcanologyMagma composition and ejection velocity are the main factors controlling pyroclast impact dynamicsTransitions between pyroclast splash and deposition can contribute to eruption style transitions and eruption dynamics [ABSTRACT FROM AUTHOR]