bluuebunny/crossref_metadata_2025_split huggingface dataset:
Modelling and control of nonlinear negative imaginary systems
Authors: Choudhary Santosh Kumar , Chokkadi Shreesha , Sudhakara G. 
Published: May 2022

AbstractThis article investigates mathematical modelling and control of a nonlinear negative imaginary system using an illustrative benchmark physical example of a quadrotor dynamic model. A generalized methodology based on Euler–Lagrange equation is applied to obtain nonlinear negative imaginary dynamic model for the quadrotor. In this method, the Kronecker product is employed to formulate the Coriolis matrix, which is then used to construct a mathematical model of a quadrotor. This article further presents nonlinear negative imaginary systems theory-based analysis and synthesis framework to find the control solution for quadrotor’s attitude stability problem while hovering. The multi-loop control scheme is applied to the quadrotor that directly uses the Euler angles (angular positions) instead of angular velocity measurements. Numerical simulation results of this paper show that the investigated control strategy ensures the asymptotic stabilization of quadrotor attitude system model in the presence of external disturbance.
Treatment for Moral Injury: Impact of Killing in War
Authors: Burkman Kristine , Gloria Rebecca , Mehlman Haley , Maguen Shira 
Published: May 2022

Abstract
Purpose of Review
Veterans who kill in war are at risk of developing negative mental health problems including moral injury, PTSD, spiritual distress, and impairments in functioning. Impact of Killing (IOK) is a novel, cognitive-behaviorally based treatment designed to address the symptoms associated with killing that focuses on self-forgiveness and moral repair through cultivation of self-compassion and perspective-taking exercises, such as letter writing, and active participation in values-driven behavior.

Recent Findings
In a pilot trial assessing IOK, participants demonstrated a reduction in multiple mental health symptoms and improvement in quality-of-life measures, and they reported IOK was acceptable and feasible. Furthermore, trauma therapists have reported that moral injury is relevant to their clinical work, expressed a desire for additional training on the impact of killing, and identified barriers that make addressing killing in clinical settings challenging. Data are currently being collected in a national multi-site trial to examine the efficacy of IOK, compared to a control condition.

Summary
IOK fills a critical treatment gap by directly addressing the guilt, shame, self-sabotaging behaviors, functional difficulties, impaired self-forgiveness, and moral/spiritual distress directly associated with killing in war. Typically provided following some initial trauma-processing treatment, IOK can be integrated in existing systems of trauma care, creating a pathway for a stepped model of treatment for moral injury.
Facilitatory Effect of Extending the Course Duration on Dissemination of Educational Content
Authors: Satoh Hiromasa , Tamalu Fuminobu , Hirosawa Narumi , Hirasawa Hajime , Nagane Mitsuo , Saito Ryohei , Watanabe Shu-Ichi , Miwa Naofumi 
Published: May 2022

AbstractThe physiological practice course at Saitama Medical University provides students with the opportunity to learn physiological principles through wet labs and discussions. To develop a more effective method for maximizing learning outcomes, we extended the course’s schedule from one day (1d) to two days (2d) per theme, evaluated self-administered questionnaires between two different years (pre and post-change), and examined whether the increased course length affected learning outcomes. Within the 2018 curriculum year, every theme of the course was completed in a day, including experiments in the wet lab and discussions. In 2019, each theme was assessed for two days. The second-year undergraduate medical students anonymously submitted the self-assessment questionnaire that addressed several aspects, such as understanding of the theme, through a 5-point Likert scale. The average Likert scores varied from 4 to 4.5 point for all questions, and significant differences were not found between the 1d and 2d courses. However, the ratio of students with the highest points increased for one question of the 2d course: 43.6% (1d) to 53.4% (2d) for understanding. Further, the standard deviation (SD) values decreased in the 2d course for every question: 0.29 (1d) to 0.15 (2d) for interest, 0.33 (1d) to 0.19 (2d) for understanding, 0.30 (d) to 0.17 (d) for communication, 0.34 (1d) to 0.19 (2d) for general evaluation. This reduction in the SD values indicated that the educational content was imparted more efficiently to students in the 2d course. Thus, we concluded that extending the course time facilitated dissemination of educational content for every theme.
Ginsenoside Rg2 Attenuates Doxorubicin-induced Cardiomyocyte Apoptosis via the PI3K/Akt Pathway
Authors: Qiu Boyong , Mao Meijiao , Ma Zilin , Deng Bing , Shen Lin , Zhou Duan , Zheng Wang , Wei Yihong 
Published: May 2022

AbstractDoxorubicin, sold under the brand name Adriamycin among others, is an important drug for cancer therapy; however, its use is limited by its cardiotoxicity. Ginsenoside Rg2 is extracted from Panax ginseng C.A.Mey., Araliaceae, which is believed to have cardioprotective properties. However, to date, there have been no reports on whether ginsenoside Rg2 could protect cardiomyocytes against doxorubicin. In this study, we investigated the action and the underlying mechanisms of cardioprotection of ginsenoside Rg2 upon doxorubicin treatment. Cell counting kit-8 was used to determine cell viability; in addition, terminal deoxynucleotidyl transferase–mediated dUTP nick-end labeling staining was used to detect apoptotic cells. Western blotting was used to investigate the relevant pathways. LY294002, a phosphatidylinositol 3-kinase inhibitor, was also used in this study. Ginsenoside Rg2 significantly (p < 0.01) neutralized cardiomyocyte apoptosis induced by doxorubicin in a dose-dependent manner, but this effect was blocked by LY294002. Furthermore, ginsenoside Rg2 upregulated protein kinase B phosphorylation through the phosphatidylinositol 3-kinase/protein kinase B pathway and inhibited p53 expression. These results suggest that ginsenoside Rg2 could attenuate doxorubicin-induced cardiomyocyte apoptosis via the phosphatidylinositol 3-kinase/protein kinase B pathway.
Graphical abstract
Synthesis and characterization of alkali-activated materials containing biomass fly ash and metakaolin: effect of the soluble salt content of the residue
Authors: Jurado-Contreras S. , Bonet-Martínez E. , Sánchez-Soto P. J. , Gencel O. , Eliche-Quesada D. 
Published: May 2022

AbstractThe present study investigates the production and characterization of alkali-activated bricks prepared with mixing metakaolin (MK) and biomass fly ash from the combustion of a mix of pine pruning, forest residues and energy crops (BFA). To use this low cost and high availability waste, different specimens were prepared by mixing MK with different proportions of BFA (25, 50 and 75 wt%). Specimens containing only metakaolin and biomass fly ash were produced for the purpose of comparison. Effects of the alkali content of biomass fly ash, after a washing pretreatment (WBFA), as well as the concentration of NaOH solution on the physical, mechanical and microstructural properties of the alkali-activated bricks were studied. It was observed that up to 50 wt% addition of the residue increases compressive strength of alkali-activated bricks. Alkalinity and soluble salts in fly ash have a positive effect, leading materials with the improved mechanical properties. Concentration of NaOH 8 M or higher is required to obtain optimum mechanical properties. The compressive strength increases from 23.0 MPa for the control bricks to 44.0 and 37.2 MPa with the addition of 50 wt% BFA and WBFA, respectively, indicating an increase of more than 60%. Therefore, the use of biomass fly ash provides additional alkali (K) sources that could improve the dissolution of MK resulting in high polycondensation. However, to obtain optimum mechanical properties, the amount of BFA cannot be above 50 wt%.
Gender bias in the medical school admission system in Japan
Authors: Fukami Kayo , Okoshi Kae , Tomizawa Yasuko 
Published: May 2022

AbstractThe 2018 Japanese Ministry of Education, Culture, Sports, Science, and Technology (MEXT) survey revealed discrimination against women in the admissions process of four Japanese medical schools, although it is not known how unusual the trend is for entire medical schools to enroll men and women. Therefore, this paper aims to examine how women are disadvantaged when they take entrance examinations for medical schools in Japan, compared to other academic disciplines. A null hypothesis that the average enrollment rates by gender in each academic discipline from 2015 to 2020 are the same was used to test the population ratio, and p-values were calculated. The results showed that no significant gender differences were found in the other disciplines, but the male enrollment rate was significantly higher only in medical schools (p < 0.01). This could be because the academic performance of men exceeds that of women in admissions. However, the percentage of women who passed the national examination for medical practitioners has been consistently high since 1997, suggesting that women were subjected to more difficult admission standards than their male counterparts or may have performed better during their years at medical school. As university entrance examinations in Japan are conducted in a closed environment, further information is expected to be disclosed as the matter continues to attract social attention for a better admission system.
Civil War Settlers
Authors: Rasmussen Anders Bo 
Published: May 2022

Civil War Settlers is the first comprehensive analysis of Scandinavian Americans and their participation in the US Civil War. Based on thousands of sources in multiple languages, that have to date been inaccessible to most US historians, Anders Bo Rasmussen brings the untold story of Scandinavian American immigrants to life by focusing on their lived community experience and positioning it within the larger context of western settler colonialism. Associating American citizenship with liberty and equality, Scandinavian immigrants openly opposed slavery and were among the most enthusiastic foreign-born supporters of the early Republican Party. However, the malleable concept of citizenship was used by immigrants to resist draft service, and support a white man's republic through territorial expansion on American Indian land and into the Caribbean. Consequently, Scandinavian immigrants after emancipation proved to be reactionary Republicans, not abolitionists. This unique approach to the Civil War sheds new light on how whiteness and access to territory formed an integral part of American immigration history. Also available as open access on Cambridge Core.
Possible Control of Earth's Boron Budget by Metallic Iron
Authors: Yuan Liang , Steinle‐Neumann Gerd 
Published: May 2022

AbstractBoron is considered a principal tracer for crustal recycling into the depleted mantle, and high boron anomalies and isotopically light boron (10B) in mantle‐derived samples have been interpreted as the result of subduction. Using density functional theory, we predict that boron behavior changes from lithophile to siderophile, with the calculated boron partition coefficients (Dm/s) between liquid metal and silicate ranging from log10Dm/s ≤ −0.8 at low pressure–temperature conditions (10 GPa, 3000 K) to log10Dm/s ≥ 3.7 at high pressure and temperature (130 GPa, 5000 K). We further predict that the silicate becomes enriched in the heavier boron isotope (11B) by >1‰ relative to metal at high pressure–temperature. Our results suggest that Earth's core may hold >50% of Earth's boron budget and that a high boron content in deep diamonds and isotopically light boron in ocean islands basalts may reflect contributions from metallic reservoirs, rather than being attributed to crustal subduction and recycling.
Antarctic Sea Ice Projections Constrained by Historical Ice Cover and Future Global Temperature Change
Authors: Holmes C. R. , Bracegirdle T. J. , Holland P. R. 
Published: May 2022

AbstractThere is low confidence in projections of Antarctic sea ice area (SIA), due to deficiencies in climate model sea ice processes. Ensemble regression techniques can help to reduce this uncertainty. We investigate relationships between SIA climatology and 21st century change in the Coupled Model Intercomparison Project, phase 6 (CMIP6) multi‐model ensemble. In summer, under a strong forcing scenario, each model loses the majority of its sea ice. Therefore, models with greater historical SIA exhibit greater reductions, so the observed climatology of SIA strongly constrains projections. Ensemble spread in historical summer SIA is smaller than in CMIP phase 5 (CMIP5), and CMIP6 gives a more robust constraint on future SIA. In winter, by 2100 under a strong forcing scenario, 40% of SIA disappears on average, and ensemble spread in historical mean SIA explains approximately half the spread in projected change. A greater winter ice loss in CMIP6 than CMIP5 is explained by the higher climate sensitivities of some CMIP6 models.
Polar Cap Boundary Identification Using Redline Optical Data and DMSP Satellite Particle Data
Authors: Gallardo‐Lacourt B. , Wing S. , Kepko L. , Gillies D. M. , Spanswick E. L. , Roy E. A. , Donovan E. F. 
Published: May 2022

AbstractThe location of the polar cap boundary is typically determined by using low‐orbit satellite measurements in which the boundary is identified by its unique signature of a sharp decrease in energy and particle flux poleward of the auroral oval. In principle, this decrease in precipitating particles should appear as a concomitant sharp change in auroral luminosity. Based on a few events, Blanchard et al. (1995, https://doi.org/10.1029/94JA02631) suggested that a dramatic gradient in redline aurora may also be an indicator of the polar cap boundary. In recent years, advances in capabilities and the deployment of ground‐based all‐sky imagers have ushered in a new era of auroral measurements. Auroral imaging has moved well beyond the capabilities of the instrumentation in the previous study in terms of both spatial and temporal resolution. We now have access to decades of optical data from arrays spanning a huge spatial range, enabling a fresh examination of the relationship between redline aurora, particle precipitation, and the polar cap open closed boundary. In this study, we use data from the Defense Meteorological Satellite Program satellites in conjunction with the University of Calgary's Redline Emission Geospace Observatory (630.0 nm) data to assess the viability of automated detection of the 2‐dimensional polar cap boundary. Our results exhibit good agreement between the optical and particle polar cap boundary and suggest that a luminosity in redline emission could serve as a reasonable proxy for the location of the electron poleward boundary, while providing both high temporal and spatial resolution maps of the open‐closed boundary.
Satellites Suggest Rising Tropical High Cloud Altitude: 2002–2021
Authors: Richardson M. T. , Roy R. J. , Lebsock M. D. 
Published: May 2022

AbstractTropical upper‐troposphere clouds are expected to rise under global warming, contributing a positive radiative feedback. Here we show that Moderate Resolution Imaging Spectroradiometer (MODIS) retrievals over 2002–2021 from the Terra and Aqua satellites report a tropical‐mean high‐cloud altitude increase of 6.9 ± 2.7 m yr−1 (±2σ), while atmospheric models report 5.6 ± 3.0 m yr−1 over 1979–2014. During their common overlap period, however, the observed trend is greater than that of the models. The atmospheric models also show a tropically confined cloud‐height response to El Nino, whereas the observed cloud height response peak extends into the subtropics. Poleward of the mid‐latitudes, Aqua and Terra MODIS have cloud‐height drifts relative to each other, highlighting the need for deeper investigation of potential time‐dependent biases in MODIS cloud retrievals. Both sensors report significant tropical cloud height increases since 2002, which are statistically consistent with those simulated by climate models.
Impact of Rainfall on Tropical Cyclone‐Induced Sea Surface Cooling
Authors: Balaguru Karthik , Foltz Gregory R. , Leung L. Ruby , Hagos Samson M. 
Published: May 2022

AbstractTropical cyclones (TCs) are often accompanied by strong winds and torrential rains. While the winds associated with TCs tend to enhance mixing in the upper ocean, the freshwater input from rain can stratify the water column and limit mixing. However, the extent to which the stabilizing effect of rainfall can compete with wind‐induced mixing and to what degree it modulates TC‐induced sea surface cooling remain unknown. Here we show, using a suite of observations, that heavy rains under weak TCs can significantly reduce the magnitude of cold wakes induced by them. When compared to storms with low rain rates, the ocean surface under TCs with high rain rates freshens significantly and cools less. High‐resolution climate model simulations and idealized experiments with an ocean mixed layer model support these results and reveal that oceanic mixing processes are primarily responsible for reduced cooling under TCs, with a lesser role for surface fluxes.
Seismic Evidence for Stepwise Lithospheric Delamination Beneath the Tibetan Plateau
Authors: Wu Yingkai , Bao Xuewei , Zhang Bingfeng , Xu Yixian , Yang Wencai 
Published: May 2022

AbstractSeveral models were proposed to account for the tectonic evolution of Tibetan Plateau, among which delamination of the Tibetan lithosphere is suggested to be a leading process. However, direct evidence for the removed Tibetan lithosphere in the deep mantle remains highly lacking. Here we image the mantle transition zone (MTZ) structure beneath western Tibet and Himalaya by common conversion point stacking of 25254 receiver functions (RFs) with unprecedented clarity. One striking feature is the significant depression (15–20 km) of 660‐km discontinuity beneath Himalaya, which indicates the presence of the detached Lhasa lithospheric mantle (∼26 Ma) at the bottom of the MTZ. Our results also show ∼15 km uplift of 410‐km discontinuity (d410) and small d410 amplitude beneath western Tibet, which we ascribe to the more recently delaminated Qiangtang lithosphere (∼15 Ma). Furthermore, the small dependence of d410 amplitude on frequency indicates that the MTZ is anhydrous in the study area.
Geomagnetic Activity Index Hpo
Authors: Yamazaki Y. , Matzka J. , Stolle C. , Kervalishvili G. , Rauberg J. , Bronkalla O. , Morschhauser A. , Bruinsma S. , Shprits Y. Y. , Jackson D. R. 
Published: May 2022

AbstractThe geomagnetic activity index Kp is widely used but is restricted by low time resolution (3‐hourly) and an upper limit. To address this, new geomagnetic activity indices, Hpo, are introduced. Similar to Kp, Hpo expresses the level of planetary geomagnetic activity in units of thirds (0o, 0+, 1−, 1o, 1+, 2−, …) based on the magnitude of geomagnetic disturbances observed at subauroral observatories. Hpo has a higher time resolution than Kp. 30‐min (Hp30) and 60‐min (Hp60) indices are produced. The frequency distribution of Hpo is designed to be similar to that of Kp so that Hpo may be used as a higher time‐resolution alternative to Kp. Unlike Kp, which is capped at 9o, Hpo is an open‐ended index and thus can characterize severe geomagnetic storms more accurately. Hp30, Hp60 and corresponding linearly scaled ap30 and ap60 are available, in near real time, at the GFZ website (https://www.gfz-potsdam.de/en/hpo-index).
Impact of Strong and Weak Stratospheric Polar Vortices on the Mesosphere and Lower Thermosphere
Authors: Pedatella N. M. , Harvey V. L. 
Published: May 2022

AbstractThe impact of strong and weak Northern Hemisphere stratospheric polar vortices on the zonal mean and atmospheric tides in the mesosphere and lower thermosphere (MLT) is investigated using Specified Dynamics Whole Atmosphere Community Climate Model (WACCM) with thermosphere‐ionosphere eXtension (SD‐WACCM‐X) simulations and Aura Microwave Limb Sounder observations. The observed and simulated zonal mean anomalies during strong and weak vortices are in good agreement. Zonal mean and tidal anomalies during weak polar vortex events are consistent with those known to occur during sudden stratospheric warmings. Generally opposite, though weaker, anomalies are found to occur when the stratospheric polar vortex is strong. The most notable impact in the MLT is a reduction in the migrating semidiurnal tide of ∼25%–35% during strong polar vortex times. The results demonstrate that, in addition to weak polar vortex events, a strong stratospheric polar vortex can also have an appreciable impact on the middle and upper atmosphere.
Stability of a Mixed‐Valence Hydrous Iron‐Rich Oxide: Implications for Water Storage and Dynamics in the Deep Lower Mantle
Authors: Liu Lu , Yang Ziqiang , Yuan Hongsheng , Meng Yue , Giordano Nico , Sun Junliang , Du Xueyan , Dalladay‐Simpson Philip , Wang Junyue , Zhang Li 
Published: May 2022

AbstractIncorporation of water into mantle compositions can have significant effects on the phase relations in the systems. In this study, we synthesized an iron‐rich hexagonal hydrous phase (referred to as “HH1‐phase”) under the high pressure‐temperature (P‐T) conditions of the deep lower mantle and determined the crystal structure of the HH1‐phase at 79 GPa using the multigrain crystallography method. The chemical formula obtained was Fe12.76O18Hx (x ∼ 4.5) in the Fe‐O‐H system. To demonstrate the role of HH1‐phase for water storage in multicomponent systems relevant to mantle compositions, we investigated the stability of HH1‐phase in both MgO‐rich pyrolitic and SiO2‐rich basaltic compositions. Our results indicate that the HH1‐phase serves as major water storage in a pyrolitic composition, whereas the Al‐rich CaCl2‐type δ‐phase and SiO2 phase are major water storage phases in a SiO2‐rich basaltic composition. Incorporation of considerable amounts of SiO2, MgO, and Al2O3 into the HH1‐phase expands its stability field from 98 GPa in the Fe‐Al‐O‐H system to at least 108 GPa (corresponding to ∼2,400 km depth) in the Mg‐Si‐Al‐Fe‐O‐H system. Plumes of hot upwelling rock rooted at the base of the lower mantle have been proposed as a possible origin of hotspot volcanoes. The hydrous Fe‐rich HH1‐phase, if included into the material of upwelling plumes, will decompose on its rising to the upper part of the lower mantle and release water. Our results should provide constraints on water storage in the deep lower mantle and have implications for deep mantle dynamics.
High Resolution Map of Water in the Martian Regolith Observed by FREND Neutron Telescope Onboard ExoMars TGO
Authors: Malakhov A. V. , Mitrofanov I. G. , Golovin D. V. , Litvak M. L. , Sanin A. B. , Djachkova M. V. , Lukyanov N. V. 
Published: May 2022

AbstractStudies of water content in the Martian subsurface by means of neutron spectroscopy is a well‐known technique, very sensitive to water abundance. The FREND instrument onboard the ExoMars TGO is the latest experiment of that kind. Its major characteristic and advantage compared to the predecessors is its capability of high spatial resolution measurements – massive collimator shields FREND's detectors, allowing for a narrow field of view. In this study we present a global map of Water Equivalent Hydrogen (WEH) in the upper meter of the Martian subsurface, which is built based on the FREND data. We show that it contains more local features and reveals more structure than analogous maps from omnidirectional experiments, available previously. Further analysis shows that local water‐rich regions can be located through the analysis of the FREND data, some of these containing about 20 wt% of WEH – a very unusual amount for regions at moderate latitudes, where free water and water ice are thought to be unstable in the shallow subsurface.