The response of the ionosphere-thermosphere system to the August 21, 2017 solar eclipse

We simulated the effects of the 21 August 2017 total solar eclipse on the ionosphere‐thermosphere system with the Global Ionosphere Thermosphere Model (GITM). The simulations demonstrate that the horizontal neutral wind modifies the eclipse‐induced reduction in total electron content (TEC), spreading it equatorward and westward of the eclipse path. The neutral wind also affects the neutral temperature and mass density responses through advection and the vertical wind modifies them further through adiabatic heating/cooling and compositional changes. The neutral temperature response lags behind totality by about 35 min, indicating an imbalance between heating and cooling processes during the eclipse, while the ion and electron temperature responses have almost no lag, indicating they are in quasi steady state. Simulated ion temperature and vertical drift responses are weaker than observed by the Millstone Hill Incoherent Scatter Radar, while simulated reductions in electron density and temperature are stronger. The model misses the observed posteclipse enhancement in electron density, which could be due to the lack of a plasmasphere in GITM. The simulated TEC response appears too weak compared to Global Positioning System TEC measurements, but this might be because the model does not include electron content above 550‐km altitude. The simulated response in the neutral wind after the eclipse is too weak compared to Fabry Perot interferometer observations in Cariri, Brazil, which suggests that GITM recovers too quickly after the eclipse. This could be related to GITM heating processes being too strong and electron densities being too high at low latitudes

A year long comparison of GPS TEC and global ionosphere-thermosphere models

The prevalence of GPS total electron content (TEC) observations has provided an opportunity for extensive global ionosphere‐thermosphere model validation efforts. This study presents a year‐long data‐model comparison using the Global Ionosphere‐Thermosphere Model (GITM) and the Thermosphere‐Ionosphere‐Electrodynamics General Circulation Model (TIE‐GCM). For the entire year of 2010, each model was run and compared to GPS TEC observations. The results were binned according to season, latitude, local time, and magnetic local time. GITM was found to overestimate the TEC everywhere, except on the midlatitude nightside, due to high O/N2 ratios. TIE‐GCM produced much less TEC and had lower O/N2 ratios and neutral wind speeds. Seasonal and regional biases in the models are discussed along with ideas for model improvements and further validation efforts

Future Climate Change in the Thermosphere Under Varying Solar Activity Conditions

Increasing carbon dioxide concentrations in the mesosphere and lower thermosphere are increasing radiative cooling in the upper atmosphere, leading to thermospheric contraction and decreased neutral mass densities at fixed altitudes. Previous studies of the historic neutral density trend have shown a dependence upon solar activity, with larger F10.7 values resulting in lower neutral density reductions. To investigate the impact on the future thermosphere, the Whole Atmosphere Community Climate Model with ionosphere and thermosphere extension has been used to simulate the thermosphere under increasing carbon dioxide concentrations and varying solar activity conditions. These neutral density reductions have then been mapped onto the Shared Socioeconomic Pathways published by the Intergovernmental Panel on Climate Change. The neutral density reductions can also be used as a scaling factor, allowing commonly used empirical models to account for CO2 trends. Under the “best case” SSP1-2.6 scenario, neutral densities reductions at 400 km altitude peak (when CO2 = 474 ppm) at a reduction of 13%–30% (under high and low solar activity respectively) compared to the year 2000. Higher CO2 concentrations lead to greater density reductions, with the largest modeled concentration of 890 ppm resulting in a 50%–77% reduction at 400 km, under high and low solar activity respectively

An Integrated Agent Model Addressing Situation Awareness and Functional State in Decision Making

In this paper, an integrated agent model is introduced addressing mutually interacting Situation Awareness and Functional State dynamics in decision making. This shows how a human's functional state, more specific a human's exhaustion and power, can influence a human's situation awareness, and in turn the decision making. The model is illustrated by a number of simulation scenarios. © 2011 Springer-Verlag

Psychometrics of the patient-reported outcomes measurement information system measures in hemophilia:the applicability of the pediatric item banks

Background: The use of patient-reported outcomes measures (PROMs) is important in hemophilia care, as it facilitates communication between patients and clinicians and promotes patient-centered care. Currently, a variety of PROMs with insufficient psychometric properties are used. Patient-reported outcomes measurement information system (PROMIS) measures, including Computer Adaptive Tests, were designed to measure generically and more efficiently and, therefore, are an alternative for the existing PROMs. Objectives: To assess the feasibility, measurement properties, and outcomes of 8 PROMIS pediatric measures for boys with hemophilia. Methods: In this multicenter study, boys with hemophilia completed 8 PROMIS measures and 2 legacy instruments. Feasibility was determined by the number of completed items and floor or ceiling effects (percentage of participants that achieved the lowest or highest possible score). Reliability was assessed as the percentage of scores with a SE ≤ 4.5. Construct validity was evaluated by comparing the PROMIS measures with the legacy instruments. Mean PROMIS T-scores were calculated and compared with the Dutch general population. Results: In total, 77 boys with hemophilia participated. Reliability was good for almost all PROMIS measures and legacy instruments. The total number of completed items varied from 49 to 90 for the PROMIS pediatric measures, while the legacy instruments contained 117 to 130 items. Floor and ceiling effects were observed in both the PROMIS measures (0-39.5%) and legacy instruments (0-66.7%), but were higher for the legacy instruments. Conclusions: The PROMIS pediatric measures are feasible to use for boys with hemophilia. With the use of the PROMIS measures in clinical care and research, a step toward worldwide standardization of PROM administration can be taken.</p

In Vivo T1 of Blood Measurements in Children with Sickle Cell Disease Improve Cerebral Blood Flow Quantification from Arterial Spin-Labeling MRI

Children with sickle cell disease have low hematocrit and elevated CBF, the latter of which can be assessed with arterial spin-labeling MR imaging. Quantitative CBF values are obtained by using an estimation of the longitudinal relaxation time of blood (T1blood). Because T1blood depends on hematocrit in healthy individuals, we investigated the importance of measuring T1blood in vivo with MR imaging versus calculating it from hematocrit or assuming an adult fixed value recommended by the literature, hypothesizing that measured T1blood would be the most suited for CBF quantification in children with sickle cell disease. Four approaches for T1blood estimation were investigated in 39 patients with sickle cell disease and subsequently used in the CBF quantification from arterial spin-labeling MR imaging. First, we used 1650 ms as recommended by the literature (T1blood-fixed); second, T1blood calculated from hematocrit measured in patients (T1blood-hematocrit); third, T1blood measured in vivo with a Look-Locker MR imaging sequence (T1blood-measured); and finally, a mean value from T1blood measured in this study in children with sickle cell disease (T1blood-sickle cell disease). Quantitative flow measurements acquired with phase-contrast MR imaging served as reference values for CBF. T1blood-measured (1818 ± 107 ms) was higher than the literature recommended value of 1650 ms, was significantly lower than T1blood-hematocrit (2058 ± 123 ms, P < .001), and, most interesting, did not correlate with hematocrit measurements. Use of either T1blood-measured or T1blood-sickle cell disease provided the best agreement on CBF between arterial-spin labeling and phase-contrast MR imaging reference values. This work advocates the use of patient-specific measured T1blood or a standardized value (1818 ms) in the quantification of CBF from arterial spin-labeling in children with SC

Analytical variation in factor VIII one-stage and chromogenic assays: Experiences from the ECAT external quality assessment programme

Background: Both one-stage (OSA) and chromogenic substrate assays (CSA) are used to measure factor VIII (FVIII) activity. Factors explaining analytical variation in FVIII activity levels are still to be completely elucidated. Aim: The aim of this study was to investigate and quantify the analytical variation in OSA and CSA. Methods: Factors determining analytical variation were studied in sixteen lyophilized plasma samples (FVIII activity <0.01-1.94 IU/mL) and distributed by the ECAT surveys. To elucidate the causes of OSA variation, we exchanged deficient plasma between three company set-ups. Results: On average, 206 (range 164-230) laboratories used the OSA to measure FVIII activity and 30 (range 12-51

Proteomic landscapes of inherited platelet disorders with different etiologies

BackgroundInherited platelet disorders (IPDs) are a heterogeneous group of rare diseases that are caused by the defects in early megakaryopoiesis, proplatelet formation, and/or mature platelet function. Although genomic sequencing is increasingly used to identify genetic variants underlying IPD, this technique does not disclose resulting molecular changes that impact platelet function. Proteins are the functional units that shape platelet function; however, insights into how variants that cause IPDs impact platelet proteomes are limited.ObjectivesThe objective of this study was to profile the platelet proteomics signatures of IPDs.MethodsWe performed unbiased label-free quantitative mass spectrometry (MS)–based proteome profiling on platelets of 34 patients with IPDs with variants in 13 ISTH TIER1 genes that affect different stages of platelet development.ResultsIn line with the phenotypical heterogeneity between IPDs, proteomes were diverse between IPDs. We observed extensive proteomic alterations in patients with a GFI1B variant and for genetic variants in genes encoding proteins that impact cytoskeletal processes (MYH9, TUBB1, and WAS). Using the diversity between IPDs, we clustered protein dynamics, revealing disrupted protein-protein complexes. This analysis furthermore grouped proteins with similar cellular function and location, classifying mitochondrial protein constituents and identifying both known and putative novel alpha granule associated proteins.ConclusionsWith this study, we demonstrate a MS–based proteomics perspective to IPDs. By integrating the effects of IPDs that impact different aspects of platelet function, we dissected the biological contexts of protein alterations to gain further insights into the biology of platelet (dys)function.Immunobiology of allogeneic stem cell transplantation and immunotherapy of hematological disease

Psychometrics of the patient-reported outcomes measurement information system measures in hemophilia: the applicability of the pediatric item banks

Background: The use of patient-reported outcomes measures (PROMs) is important in hemophilia care, as it facilitates communication between patients and clinicians and promotes patient-centered care. Currently, a variety of PROMs with insufficient psychometric properties are used. Patient-reported outcomes measurement information system (PROMIS) measures, including Computer Adaptive Tests, were designed to measure generically and more efficiently and, therefore, are an alternative for the existing PROMs. Objectives: To assess the feasibility, measurement properties, and outcomes of 8 PROMIS pediatric measures for boys with hemophilia. Methods: In this multicenter study, boys with hemophilia completed 8 PROMIS measures and 2 legacy instruments. Feasibility was determined by the number of completed items and floor or ceiling effects (percentage of participants that achieved the lowest or highest possible score). Reliability was assessed as the percentage of scores with a SE ≤ 4.5. Construct validity was evaluated by comparing the PROMIS measures with the legacy instruments. Mean PROMIS T-scores were calculated and compared with the Dutch general population. Results: In total, 77 boys with hemophilia participated. Reliability was good for almost all PROMIS measures and legacy instruments. The total number of completed items varied from 49 to 90 for the PROMIS pediatric measures, while the legacy instruments contained 117 to 130 items. Floor and ceiling effects were observed in both the PROMIS measures (0-39.5%) and legacy instruments (0-66.7%), but were higher for the legacy instruments. Conclusions: The PROMIS pediatric measures are feasible to use for boys with hemophilia. With the use of the PROMIS measures in clinical care and research, a step toward worldwide standardization of PROM administration can be taken

Pre-injury Comorbidities Are Associated With Functional Impairment and Post-concussive Symptoms at 3-and 6-Months After Mild Traumatic Brain Injury: A TRACK-TBI Study

Introduction: Over 70% of traumatic brain injuries (TBI) are classified as mild (mTBI), which present heterogeneously. Associations between pre-injury comorbidities and outcomes are not well-understood, and understanding their status as risk factors may improve mTBI management and prognostication. Methods: mTBI subjects (GCS 13–15) from TRACK-TBI Pilot completing 3- and 6-month functional [Glasgow Outcome Scale-Extended (GOSE)] and post-concussive outcomes [Acute Concussion Evaluation (ACE) physical/cognitive/sleep/emotional subdomains] were extracted. Pre-injury comorbidities >10% incidence were included in regressions for functional disability (GOSE ≤ 6) and post-concussive symptoms by subdomain. Odds ratios (OR) and mean differences (B) were reported. Significance was assessed at p < 0.0083 (Bonferroni correction). Results: In 260 subjects sustaining blunt mTBI, mean age was 44.0-years and 70.4% were male. Baseline comorbidities >10% incidence included psychiatric-30.0%, cardiac (hypertension)-23.8%, cardiac (structural/valvular/ischemic)-20.4%, gastrointestinal15.8%, pulmonary-15.0%, and headache/migraine-11.5%. At 3- and 6-months separately, 30.8% had GOSE ≤ 6. At 3-months, psychiatric (GOSE ≤ 6: OR = 2.75, 95% CI [1.44–5.27]; ACE-physical: B = 1.06 [0.38–1.73]; ACE-cognitive: B = 0.72 [0.26–1.17]; ACE-sleep: B = 0.46 [0.17–0.75]; ACE-emotional: B = 0.64 [0.25–1.03]), headache/migraine (GOSE ≤ 6: OR = 4.10 [1.67–10.07]; ACE-sleep: B = 0.57 [0.15–1.00]; ACE-emotional: B = 0.92 [0.35–1.49]), and gastrointestinal history (ACE-physical: B = 1.25 [0.41–2.10]) were multivariable predictors of worse outcomes. At 6-months, psychiatric (GOSE ≤ 6: OR = 2.57 [1.38–4.77]; ACE-physical: B = 1.38 [0.68–2.09]; ACE-cognitive: B = 0.74 [0.28–1.20]; ACE-sleep: B = 0.51 [0.20–0.83]; ACE-emotional: B = 0.93 [0.53–1.33]), and headache/migraine history (ACE-physical: B = 1.81 [0.79–2.84]) predicted worse outcomes. Conclusions: Pre-injury psychiat