Aerodynamic stiffness of an unbound eccentric whirling centrifugal impeller with an infinite number of blades

An unbounded eccentric centrifugal impeller with an infinite number of log spiral blades undergoing synchronous whirling in an incompressible fluid is considered. The forces acting on it due to coriolis forces, centripetal forces, changes in linear momentum, changes in pressure due to rotating and changes in pressure due to changes in linear momentum are evaluated

Hydraulic forces on a centrifugal impeller undergoing synchronous whirl

High speed centrifugal rotating machinery with large vibrations caused by aerodynamic forces on impellers was examined. A method to calculate forces in a two dimensional orbiting impeller in an unbounded fluid with nonuniform entering flow was developed. A finite element model of the full impeller is employed to solve the inviscid flow equations. Five forces acting on the impeller are: Coriolis forces, centripetal forces, changes in linear momentum, changes in pressure due to rotation and pressure changes due to linear momentum. Both principal and cross coupled stiffness coefficients are calculated for the impeller

NEUROWAR IS HERE!

Mysterious attacks on the human brain have begun plaguing U.S. diplomats and officials with increasing frequency, ranging from overseas diplomatic outposts to right here in the United States. Known in the media as Havana Syndrome, these attacks appear to be signaling a new form of warfare—one that is focused on enhancing, targeting, and weaponizing the human brain—neurowarfare. Indeed, the human brain is at the center of a biotechnological revolution currently underway. At the same time, great power competition has returned to the forefront of international relations, as China and Russia seek to contest America’s global leadership. In an increasingly globalized and interconnected world, this contest is ultimately a battle of ideas and influence, with more value placed on information and non-lethal means to manipulate and control both adversaries and domestic populations alike. The battle for influence begins and ends in the human mind, where reality is perceived. The implications of these developments point to both a new form and domain of warfare centering on the human brain. By highlighting recent attacks targeting the brain and revealing research from the United States and its two main competitors—China and Russia—this thesis seeks to argue that neurowar is not just coming, but rather is already here and is likely to fundamentally alter conflict and warfare.Lieutenant Colonel, United States Air ForceMajor, United States Air ForceApproved for public release. Distribution is unlimited

Thresholds for surfactant use in preterm neonates: a network meta-analysis

Objective: To perform a network meta-analysis of randomised controlled trials of different surfactant treatment strategies for respiratory distress syndrome (RDS) to assess if a certain fraction of inspired oxygen (FiO2) is optimal for selective surfactant therapy. Design: Systematic review and network meta-analysis using Bayesian analysis of randomised trials of prophylactic versus selective surfactant for RDS. Setting: Cochrane Central Register of Controlled Trials, MEDLINE, Embase and Science Citation Index Expanded. Patients: Randomised trials including infants under 32 weeks of gestational age. Interventions: Intratracheal surfactant, irrespective of type or dose. Main outcome measures: Our primary outcome was neonatal mortality, compared between groups treated with selective surfactant therapy at different thresholds of FiO2. Secondary outcomes included respiratory morbidity and major complications of prematurity. Results: Of 4643 identified references, 14 studies involving 5298 participants were included. We found no statistically significant differences between 30%, 40% and 50% FiO2 thresholds. A sensitivity analysis of infants treated in the era of high antenatal steroid use and nasal continuous positive airway pressure as initial mode of respiratory support showed no difference in mortality, RDS or intraventricular haemorrhage alone but suggested an increase in the combined outcome of major morbidities in the 60% threshold. Conclusion: Our results do not show a clear benefit of surfactant treatment at any threshold of FiO2. The 60% threshold was suggestive of increased morbidity. There was no advantage seen with prophylactic treatment. Randomised trials of different thresholds for surfactant delivery are urgently needed to guide clinicians and provide robust evidence. PROSPERO registration number: CRD42020166620

Microseismic Monitoring of the Mounds Drill Cuttings Injection Tests

This paper describes the microseismic mapping of repeated injections of drill cuttings into two separate formations at a test site near Mounds, OK. Injections were performed in sandstone and shale formations at depths of 830 and 595 m, respectively. Typical injection disposal was simulated using multiple small-volume injections over a three-day period, with long shut-in periods interspersed between the injections. Microseismic monitoring was achieved using a 5-level array of wireline-run, triaxial- accelerometer receivers in a monitor well 76 m from the disposed well. Results of the mapped microseismic locations showed that the disposal domti W= generally aligns with the major horizontal stress with some variations in azimuth and that wide variations in height and length growth occurred with continued injections. These experiments show that the cuttings injection process cm be adequately monitored from a downhole, wireline-run receiver array, thus providing process control and environmental assurance

Extent of alteration, paleomagnetic history, and infrared spectral properties of the Tarda ungrouped carbonaceous chondrite

Tarda is an ungrouped, hydrated carbonaceous chondrite (C2‐ung) that was seen to fall in Morocco in 2020. Early studies showed that Tarda chemically resembles another ungrouped chondrite, Tagish Lake (C2‐ung), which has previously been linked to the dark D‐type asteroids. Samples of D‐type asteroids provide an important opportunity to investigate primitive conditions in the outer solar system. We show that Tarda contains few intact chondrules and refractory inclusions and that its composition is dominated by secondary Mg‐rich phyllosilicates (>70 vol%), carbonates, oxides, and Fe‐sulfides that formed during extensive water–rock reactions. Quantitative assessment of first‐order reversal curve (FORC) diagrams shows that Tarda's magnetic mineralogy (i.e., framboidal magnetite) is comparable to that of the CI chondrites and differs notably from that of most CM chondrites. These traits support a common formation process for magnetite in Tarda and the CI chondrites. Furthermore, Tarda's pre‐terrestrial paleomagnetic remanence is similar to that of Tagish Lake and samples returned from asteroid Ryugu, with a very weak paleointensity (5.4–8.3 AU. An origin in the cold, outer regions of the solar system is further supported by the presence of distinct, porous clasts enriched in aliphatic‐rich organics that potentially retain a pristine interstellar composition. Together, our observations support a genetic relationship between Tarda and Tagish Lake

Design of design: Learning dynamics in design degree

Though different College’s curriculums in Design point to different objectives, there may be low awareness about different stakeholder’s real needs in issues like design relevance, planning, production, marketing, selling and recycling of designed products. The curricular programs include the approximation of the Design students (DS) to the job market with the purpose of professional success. However, the labor-market-approach focus must also include the challenge of entrepreneurship, based on the transformation of DS projects into competitive products. Having in mind the relevance of the analysis of DS entrepreneurship predisposition, and the need to stimulate this target to transform the DS skills in order to develop business, this paper intends to: (1) profile the DS regarding their entrepreneurial competencies and capabilities, and (2) to know how to tailor Design curriculum and proposing tools (Canvas) in order to develop/align new DS skills for development/implementation of business projects.info:eu-repo/semantics/acceptedVersio

Population-based observational study of acute pancreatitis in southern England

Introduction Acute pancreatitis is a common surgical emergency. Identifying variations in presentation, incidence and management may assist standardisation and optimisation of care. The objective of the study was to document the current incidence management and outcomes of acute pancreatitis against international guidelines, and to assess temporal trends over the past 20 years. Methods A prospective four-month audit of patients with acute pancreatitis was performed across the Wessex region. The Atlanta 2012 classifications were used to define cases, severity and complications. Outcomes were recorded using validated systems and correlated against guideline standards. Case ascertainment was validated with clinical coding and hospital episode statistics data. Results A total of 283 patient admissions with acute pancreatitis were identified. Aetiology included 153 gallstones (54%), 65 idiopathic (23%), 29 alcohol (10%), 9 endoscopic retrograde cholangiopancreatography (3%), 6 drug related (2%), 5 tumour (2%) and 16 other (6%). Compliance with guidelines had improved compared with our previous regional audit. Results were 6.5% mortality, 74% severity stratification, 23% idiopathic cases, 65% definitive treatment of gallstones within 2 weeks, 39% computed tomography within 6–10 days of severe pancreatitis presentation and 82% severe pancreatitis critical care admission. The Atlanta 2012 severity criteria significantly correlated with critical care stay, length of stay, development of complications and mortality (2% vs 6% vs 36%, P < 0.0001). Conclusions The incidence of acute pancreatitis in southern England has risen substantially. The Atlanta 2012 classification identifies patients with severe pancreatitis who have a high risk of fatal outcome. Acute pancreatitis management is seen to have evolved in keeping with new evidence and updated clinical guidelines

DyeVert™ PLUS EZ System for Preventing Contrast-Induced Acute Kidney Injury in Patients Undergoing Diagnostic Coronary Angiography and/or Percutaneous Coronary Intervention: A UK-Based Cost–Utility Analysis

Background: Contrast-induced acute kidney injury (CI-AKI) is a complication commonly associated with invasive angiographic procedures and is considered the leading cause of hospital-acquired acute kidney injury. CI-AKI can lead to a prolonged hospital stay, with a substantial economic impact, and increased mortality. The DyeVert™ PLUS EZ system (FDA approved and CE marked) is a device that has been developed to divert a portion of the theoretical injected contrast media volume (CMV), reducing the overall volume of contrast media injected and aortic reflux, and potentially improving long-term health outcomes. Objectives: To assess the long-term costs and health outcomes associated with the introduction of the DyeVert™ PLUS EZ system into the UK health care service for the prevention of CI-AKI in a cohort of patients with chronic kidney disease (CKD) stage 3–4 undergoing diagnostic coronary angiography (DAG) and/or percutaneous coronary intervention (PCI), and to compare these costs and outcomes with those of the current practice. Methods: A de novo economic model was developed based on the current pathway of managing patients undergoing DAG and/or PCI and on evidence related to the clinical effectiveness of DyeVert™ in terms of its impact on relevant clinical outcomes and health service resource use. Clinical data used to populate the model were derived from the literature or were based on assumptions informed by expert clinical input. Costs included in the model were from the NHS and personal social services perspective and obtained from the literature and UK-based routine sources. Probabilistic distributions were assigned to the majority of model parameters so that a probabilistic analysis could be undertaken, while deterministic sensitivity analyses were also carried out to explore the impact of key parameter variation on the model results. Results: Base-case results indicate that the intervention leads to cost savings (− £435) and improved effectiveness (+ 0.028 QALYs) over the patient’s lifetime compared with current practice. Output from the probabilistic analysis points to a high likelihood of the intervention being cost-effective across presented willingness-to-pay (WTP) thresholds. The overall long-term cost saving for the NHS associated with the introduction of the DyeVert™ PLUS EZ system is over £19.7 million for each annual cohort of patients. The cost savings are mainly driven by a lower risk of subsequent diseases and their associated costs. Conclusions: The introduction of the DyeVert™ PLUS EZ system has the potential to reduce costs for the health care service and yield improved clinical outcomes for patients with CKD stage 3–4 undergoing angiographic procedures

A Kernel to Exploit Informative Missingness in Multivariate Time Series from EHRs

A large fraction of the electronic health records (EHRs) consists of clinical measurements collected over time, such as lab tests and vital signs, which provide important information about a patient's health status. These sequences of clinical measurements are naturally represented as time series, characterized by multiple variables and large amounts of missing data, which complicate the analysis. In this work, we propose a novel kernel which is capable of exploiting both the information from the observed values as well the information hidden in the missing patterns in multivariate time series (MTS) originating e.g. from EHRs. The kernel, called TCK$_{IM}$, is designed using an ensemble learning strategy in which the base models are novel mixed mode Bayesian mixture models which can effectively exploit informative missingness without having to resort to imputation methods. Moreover, the ensemble approach ensures robustness to hyperparameters and therefore TCK$_{IM}$ is particularly well suited if there is a lack of labels - a known challenge in medical applications. Experiments on three real-world clinical datasets demonstrate the effectiveness of the proposed kernel.Comment: 2020 International Workshop on Health Intelligence, AAAI-20. arXiv admin note: text overlap with arXiv:1907.0525