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The effects of three types of flight simulator visual scene detail on detection of altitude change were evaluated in three experiments. Across all experiments and with a variety of tasks and display conditions, speed and accuracy of detecting altitude change improved with increases in the density of vertical objects in scenes. Adding detail to individual objects to increase their natural appearance produced no consistent effects on performance. In Experiment 3 complex texture distributed globally on terrain surfaces improved detection of altitude change but did not alleviate the need for high object density. These results indicate that available computer image generator processing capacity would be used more effectively by increasing the density of objects in scenes, rather than by increasing the complexity and detail of individual objects. Complex texture is used more effectively when distributed globally on terrain surfaces, rather than when allocated to individual objects. [ABSTRACT FROM AUTHOR]

Background: Extracorporeal membrane oxygenation (ECMO) is a lifesaving therapy in patients with acute respiratory distress syndrome (ARDS). Hemostatic complications are frequently observed in patients on ECMO and limit the success of this therapy. Platelets are key mediators of hemostasis enabling activation, aggregation, and thrombus formation by coming in contact with exposed matrix proteins via their surface receptors such as glycoprotein (GP) VI or GPIb/V/IX. Recent research has elucidated a regulatory role of the GPV subunit. The cleaved soluble GPV (sGPV) ectodomain was identified to spatiotemporally control fibrin formation through complex formation with thrombin., Objectives: We aimed to decipher the impact of ECMO on platelet phenotype and function, including the role of GPV and plasmatic sGPV., Methods: We recruited 36 patients with ARDS in the wake of COVID-19 pneumonia and performed a longitudinal comparison of platelet phenotype and function in non-ECMO (n = 23) vs ECMO (n = 13) compared with those of healthy controls. Patients were assessed at up to 3 time points (t 1  = days 1-3; t 2  = days 4-6; and t 3  = days 7-14 after cannulation/study inclusion)., Results: Agonist-induced platelet activation was assessed by flow cytometry and revealed decreased GPIIb/IIIa activation and α-granule release in all ARDS patients. During ECMO treatment, agonist-induced δ-granule release continuously decreased, which was independently confirmed by electron microscopy and was associated with a prolonged in vitro bleeding time. GPV expression on the platelet surface markedly decreased in ECMO patients compared with that in non-ECMO patients. Plasma sGPV levels were increased in ECMO patients and were associated with poor outcome., Conclusion: Our data demonstrate an ECMO-intrinsic platelet δ-granule deficiency and hemostatic dysfunction beyond the underlying ARDS., Competing Interests: Declaration of competing interests There are no competing interests to disclose., (Copyright © 2024 International Society on Thrombosis and Haemostasis. Published by Elsevier Inc. All rights reserved.)

The rapid advancement of biosensor technology has revolutionized healthcare, offering improved sensitivity, specificity, and portability. We have developed an optical cavity-based biosensor (OCB) as a promising solution due to its label-free detection, high sensitivity, real-time monitoring, multiplexing capability, and versatility. The OCB consists of an optical cavity structure (OCS), optical components, and a low-cost camera. The OCS is created by two partially reflective surfaces separated by a small gap, where the interaction between target analytes and immobilized receptors leads to a shift in the resonance transmission spectrum, caused by minute changes in the local refractive index (RI). In our previous work, we successfully detected these small changes with a simple OCS and cost-effective components using a differential detection method. Building upon these achievements, this study focuses on optimizing the OCS, improving the camera settings, and enhancing the differential detection approach. By increasing the reflectance of the surfaces and optimizing the optical cavity widths correspondingly, we achieved an improved limit of detection (LOD). We also investigated how the charge-coupled device (CCD) camera shutter time affects the LOD. Additionally, we introduced a new differential equation to further enhance the sensitivity of our system. Through these advancements, we could improve the LOD of the OCB by 7.2 times, specifically for an OCS with a cavity thickness of 9.881 μ m and a silver thickness of 46.87 nm. These findings not only contribute to the ongoing effort of optimizing the OCB, but also pave the way for the development of advanced point-of-care biosensors with enhanced detection capabilities.

Thromboembolic events are frequent and life-threating complications of COVID-19 but are also observed in patients with sepsis. Disseminated thrombosis can occur despite anticoagulation, suggesting that platelets play a direct but incompletely understood role. Several studies demonstrated altered platelet function in COVID-19 with some controversial findings, while underlying disease-specific mechanisms remain ill defined. We performed a comprehensive cohort study with 111 patients, comprising 37 with COVID-19, 46 with sepsis, and 28 with infection, compared with control participants. Platelet phenotype and function were assessed under static and flow conditions, revealing unexpected disease-specific differences. From hospital admission onward, platelets in COVID-19 failed to activate the integrin glycoprotein IIb/IIa (GPIIb/IIIa) in response to multiple agonists. Dense granule release was markedly impaired due to virtually missing granules, also demonstrated by whole-mount electron microscopy. By contrast, α-granule marker CD62P exposure was only mildly affected, revealing a subpopulation of PAC-1-/CD62P+ platelets, independently confirmed by automated clustering. This uncoupling of α-granule release was not observed in patients with sepsis, despite a similar disease severity. We found overall unaltered thrombus formation in COVID-19 and sepsis samples under venous shear rates, which was dependent on the presence of tissue factor. Unexpectedly, under arterial shear rates, thrombus formation was virtually abrogated in sepsis, whereas we detected overall normal-sized and stable thrombi in blood from patients with COVID-19. These thrombi were susceptible to subthreshold levels of GPIIb/IIIa blockers, eptifibatide, or tirofiban that had only a minor effect in control participants' blood. We provide evidence that low-dose GPIIb/IIIa blockade could be a therapeutic approach in COVID-19., (© 2023 by The American Society of Hematology. Licensed under Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International (CC BY-NC-ND 4.0), permitting only noncommercial, nonderivative use with attribution. All other rights reserved.)

Asthma is one of the most common causes of school absenteeism, and many children are affected by, or encounter, it in the school setting. An integrated curriculum that presents asthma as a real world example can raise all children's awareness and understanding of asthma, not just those with the condition. A 15-lesson, asthma-based curriculum was developed to integrate with and enhance the core subjects of math, science, and communication arts. A pilot test was performed in fourth- and fifth-grade classes to assess student asthma knowledge gain, teacher acceptance, and grade appropriateness of the curriculum. During the 2006-2007 school year, 15 teachers were recruited from the St. Louis, MO, USA area to assess the curriculum through teaching and administering pre- and post-unit tests and completing a teacher evaluation for each lesson taught. Four additional classrooms served as comparisons. Paired t tests were used for each lesson taught, to evaluate pre-/post-test and classroom differences, and focus groups were used for qualitative evaluation. There was an increase in asthma knowledge between pre- and post-tests in both grades, individually and combined (p < 0.001). Intervention post-test scores were higher than comparison classroom scores (p < 0.001). Teacher feedback indicated that the lessons enhanced previously learned skills and increased students' overall understanding of asthma. Offering asthma education in the classroom can provide an opportunity for all students to gain asthma knowledge and build health literacy about a leading chronic disease in school-aged children.

Previous research indicates that pilots of most jet-fighter aircraft attend to similar elements of the natural flight environment when flying at low altitudes. However, some evidence suggests that differences may exist for pilots of certain specific types of aircraft. The present experiment examined the influence of operational factors on the perceived structure of real-world scenes viewed during low-altitude flight. Multidimensional scaling analyses with stimuli consisting of videotape segments of low-altitude flight over a variety of real-world terrains revealed differences in perceived environmental structure for pilots assigned to different types of jet-fighter aircraft. These results provide evidence that perceptual learning evolves differently under different operational conditions and suggests that training programs should be designed to reflect those differences.

In the present experiments I sought to identify the properties of visual scenes relevant for simulating low-altitude flight. The approach was first to identify the relevant properties of real-world scenes. The stimuli were videotape segments or still photographs of real-world scenes exhibiting a variety of scene properties. Ratings of similarity between stimulus pairs were submitted to multidimensional scaling analyses. Results using videotape segments provided consistent evidence for two relevant scene properties: variation in terrain shape and variation in object size or spacing. Results using still photographs were less interpretable, supporting the argument that motion information is important. Results suggest that designers of flight simulator visual scenes should focus specifically on rendering elements of terrain shape and objects in scenes.

Although there is considerable evidence that stimuli such as digits and letters are extensively processed in parallel and without capacity limitations, recent data suggest that only the features of stimuli are processed in parallel. In an attempt to reconcile this discrepancy, we used the simultaneous/successive detection paradigm with stimuli from experiments indicating parallel processing and with stimuli from experiments indicating that only features can be processed in parallel. In Experiment 1, large differences between simultaneous and successive presentations were obtained with an R target among P and Q distractors and among P and B distractors, but not with digit targets among letter distractors. As predicted by the feature integration theory of attention, false-alarm rates in the simultaneous condition were much higher than in the successive condition with the R/PQ stimuli. In Experiment 2, the possibility that attention is required for any difficult discrimination was ruled out as an explanation of the discrepancy between the digit/letter results and the R/PQ and R/PB results. Experiment 3A replicated the R/PQ and R/PB results of Experiment 1, and Experiment 3B extended these findings to a new set of stimuli. In Experiment 4, we found that large amounts of consistent practice did not generally eliminate capacity limitations. From this series of experiments we strongly conclude that the notion of capacity-free letter perception has limited generality.