Advanced Emissions Solutions (United States)

Background/Objectives: Prediction models are implemented frequently, yet, compared with other study designs, their incorporation of clinical measurements (CMs; i.e., vital signs and laboratory results) is rather underdeveloped. The purpose is to describe methods used and illustrate clinical utility in parameters systematically derived from CMs; as a case study, we use the risk of all-cause mortality following coronavirus disease 2019 (COVID-19) as the basis for prognosis. Methods: We identified cases through the Department of Veterans Affairs COVID-19 Shared Data Resource, utilizing data from the first visit until 14 days before testing positive. Thirteen parameters were derived from each of the 11 CMs, capturing departures from normality considering variability and time. The 143 candidate predictors were used to generate the main logistic regression model. The area under the receiver operating characteristic curve (AUROC) analysis was performed to assess discrimination between those who lived and died for subset and main regressions; for comparison, this was performed for an age-only model and the Charlson Comorbidity and Elixhauser Indices. Results: There were 329,491 patients. The main model's AUROC (0.785 ± 0.002) was similar to the age-only model (0.783 ± 0.002; p > 0.05) and significantly greater than the comorbidity indices' (range: 0.675 ± 0.002 to 0.729 ± 0.002; p < 0.001 each). Conclusions: The study found several parameters were significant determinants of mortality following COVID-19, highlighting the importance of a systematic approach for multivariate modeling to obtain informative insights into underlying pathophysiology. The main model outperforms common comorbidity indices as a summary metric for pre-existing conditions in this case study. If validated, this approach could revolutionize the way CMs are handled in multivariate models.

Patients with Postural Orthostatic Tachycardia Syndrome (POTS) and Orthostatic Intolerance (OI) commonly present with symptoms suggestive of Pelvic Venous Disorders (PeVD). The presence of PeVD may contribute to orthostatic symptoms in these patients due to venous obstruction with stasis and pooling. Iliac vein compression, a PeVD, has historically been treated with iliac venous stenting. The authors hypothesize that patients with POTS frequently have findings of PeVD, that venous outflow obstruction from iliac vein compression exacerbates POTS/OI symptomatology, and that treating PeVD improves POTS/OI symptoms. This paper reports results from two studies at two different institutions with a partially overlapping patient population. The first was a retrospective cross-sectional observational study of patients with POTS/OI who presented to Emory University Cardiology (Atlanta, GA, USA) from October 2019 to June 2023. We aimed to evaluate the prevalence of concurrent POTS/OI and PeVD using screening pelvic venous ultrasound, MR and/or CT, compared to venogram with intravascular ultrasound (IVUS). We secondarily evaluated the efficacy of each imaging modality in screening accuracy for PeVD. The second study was a retrospective review of medical records for 271 female patients with POTS/OI who received treatment of PeVD with iliac vein stenting from June 2019 to November 2024 at Minimally Invasive Procedure Specialists (Highlands Ranch, CO). The primary objective of this study was to explore quality of life (QoL) outcomes in female patients with POTS/OI before and after treatment. The secondary objective was to record the prevalence of associated pelvic pain, systemic symptoms, and response to therapy in this population. In the first cohort, 129 patients (84% cis female) with a diagnosis of POTS/OI and symptoms of PeVD were assessed by standard imaging for venous pathology. 107 patients (83%) had confirmed pelvic venous compression (iliac vein, renal vein, or both) or pelvic venous congestion on imaging with at least one screening modality. All screening modalities were relatively insensitive in detecting iliac venous compression compared with venography and IVUS. In the second cohort, following iliac vein stenting, significant improvements were seen in Orthostatic Hypotension Questionnaire (OHQ) composite scores at three months (p < 0·001) and at 12 months (p < 0·001). The OHQ Symptom Assessment (OHSA) and Daily Activities Scale (OHDAS) subscores, International Pelvic Pain Society (IPPS) score, Pelvic Congestion Syndrome (PCS) score, Pelvic Pain and Urgency/Frequency Symptom Scale (PUF) score, and Ancillary symptom score all demonstrated statistically significant decreases at three months that persisted at 12 months (all p < 0·001) as well. The high prevalence of PeVD in POTS/OI patients suggests an association between the two diagnoses. In the absence of expert clinical review, screening with US, CT, and MR may not be sufficient to rule out PeVD. Significant improvements were seen in QoL in patients with POTS/OI and PeVD who underwent iliac vein stenting. These results call for additional trials to examine the clinical and hemodynamic effects of venous stenting on POTS/OI symptomatology and associated systemic symptoms, including pelvic pain. These studies received no funding.

In the UK, the COVID-19 Genomics UK Consortium (COG-UK) established a real-time national genomic surveillance system during the COVID-19 pandemic, producing centralized data for monitoring severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). As a COG-UK partner, Quadram Institute Bioscience in Norfolk sequenced over 87,000 SARS-CoV-2 genomes as part of the national effort, contributing to the region becoming densely sequenced. Retrospective analysis of SARS-CoV-2 lineage dynamics in this region may contribute to preparedness for future pandemics. In total, 29,406 SARS-CoV-2 whole genome sequences and corresponding metadata from Norfolk were extracted from the COG-UK dataset, sampled between March 2020 and December 2022, representing 9.9% of regional COVID-19 cases. Sequences were lineage typed using Pangolin, with subsequent lineage analysis carried out in R using RStudio and related packages, including graphical analysis using ggplot2. In total, 401 global lineages were identified, with 69.8% appearing more than once and 31.2% over ten times. Temporal clustering identified six lineage communities based on first lineage emergence. Alpha, Delta and Omicron variants of concern (VOCs) accounted for 8.6, 34.9 and 48.5% of sequences, respectively. These formed four regional epidemic waves alongside the remaining lineages which were observed in the early pandemic prior to VOC designation and were termed 'pre-VOC' lineages. Regional comparison highlighted variability in VOC epidemic wave dates dependent on location. This study is the first to assess SARS-CoV-2 diversity in Norfolk across a large timescale within the COVID-19 pandemic. SARS-CoV-2 was both highly diverse and dynamic throughout the Norfolk region between March 2020 and December 2022, with a strong VOC presence within the latter two-thirds of the study period. The study also displays the utility of incorporating genomic epidemiological methods into pandemic response.

Enhanced real-time onboard orbit determination for low-Earth-orbit satellites is essential for autonomous spacecraft operations. However, the accuracy of such systems is often limited by signal propagation delays between GPS satellites and the user spacecraft. These delays, primarily due to Earth’s rotation and ionospheric effects become particularly significant in high-dynamic LEO environments, leading to considerable errors in range and range rate measurements, and consequently, in position and velocity estimation. To mitigate these issues, this paper proposes a real-time orbit determination algorithm that applies Earth rotation correction and dual-frequency (L1 and L2) ionospheric compensation to raw GPS measurements. The enhanced orbit determination method is processed directly in the Earth-centered Earth-fixed frame, eliminating repeated coordinate transformations and improving integration with ground-based systems. The proposed method employs a reduced-dynamic orbit determination strategy to balance model fidelity and computational efficiency. A predictive correction model is also incorporated to compensate for GPS signal delays under dynamic motion, thereby enhancing positional accuracy. The overall algorithm is embedded within an extended Kalman filter framework, which assimilates the corrected GPS observations with a stochastic process noise model to account for dynamic modeling uncertainties. Simulation results using synthetic GPS measurements, including pseudoranges and pseudorange rates from a dual-frequency spaceborne receiver, demonstrate that the proposed method provides a significant improvement in orbit determination accuracy compared to conventional techniques that neglect signal propagation effects. These findings highlight the importance of performing orbit estimation directly in the Earth-centered, Earth-fixed reference frame, utilizing pseudoranges that are corrected for ionospheric errors, applying reduced-dynamic filtering methods, and compensating for signal delays. Together, these enhancements contribute to more reliable and precise satellite orbit determination for missions operating in low Earth orbit.

Abstract Internet service providers seek to increase revenue by reducing costs and increasing subscriptions. We take a systems security engineering approach to evaluate ways of enhancing customer modem cybersecurity, using a system dynamics model to show the impact of different solutions for improving customer modem bandwidth. The model is extensible and modifiable to test other stakeholder goals. We demonstrate this by modelling customer goodwill and solution cost. When used as a tool for planning system changes, the model can be compared to the live system before and during incremental system changes. This helps improve model validity, control risk, evaluate return on investment, and provide a platform for testing proposed system changes. Businesses with similar cyber vulnerabilities can benefit from using this system engineering approach.

The public, capital I Internet, at its heart, is a mechanism for moving data from one computer to another. The World Wide Web is a combination of servers, clients (web browsers), and code that use the Internet to move data (web pages) from servers anywhere in the world to the web browser on your phone or on your desktop computer. Email is a different application that also uses the Internet to deliver its content. The Web is not the Internet. Email is not the Internet. The web and email are applications that use the Internet.

Up until now, we’ve been focusing on getting you up to speed in Linux enough to be comfortable using Raspbian, and getting you up to speed in WiringPi enough to do things you already knew how to do with Arduino. Here’s where those two paths merge. From here on, we’ll be doing things with the Raspberry Pi that you can’t easily do with Arduino without adding a lot of (expensive) shields or buying a (somewhat expensive) Arduino Yun. The first of those things is multitasking.