A trajectory generation and system characterization model for cislunar low-thrust spacecraft. Volume 2: Technical manual

The documentation of the Trajectory Generation and System Characterization Model for the Cislunar Low-Thrust Spacecraft is presented in Technical and User's Manuals. The system characteristics and trajectories of low thrust nuclear electric propulsion spacecraft can be generated through the use of multiple system technology models coupled with a high fidelity trajectory generation routine. The Earth to Moon trajectories utilize near Earth orbital plane alignment, midcourse control dependent upon the spacecraft's Jacobian constant, and capture to target orbit utilizing velocity matching algorithms. The trajectory generation is performed in a perturbed two-body equinoctial formulation and the restricted three-body formulation. A single control is determined by the user for the interactive midcourse portion of the trajectory. The full spacecraft system characteristics and trajectory are provided as output

Diffusion et migration de l'eau polluée le long des plages belges: nouvelle expérience avec rejet de 100 kg de rhodamine B: conclusions préliminaires

A solution of one hundred kilograms of B rhodamine was introduced in a sewer which discharges into the sea. The dispersion of the discharge was observed and located by means of 4 optical theodolites and by air photographs. Water samples were collected in the coloured plume and on its boundaries during a whole tidal cycle. They were analysed by spectrofluorimetry. The results demonstrate the complexity of the factors that affect water movements. The drift seems to be mainly due to the wind. The predominating winds contribute to maintain the waste water closely to the water line over a distance of several miles

Amino acid substitutions within the heptad repeat domain 1 of murine coronavirus spike protein restrict viral antigen spread in the central nervous system.

Targeted recombination was carried out to select mouse hepatitis viruses (MHVs) in a defined genetic background, containing an MHV-JHM spike gene encoding either three heptad repeat 1 (HR1) substitutions (Q1067H, Q1094H, and L1114R) or L1114R alone. The recombinant virus, which expresses spike with the three substitutions, was nonfusogenic at neutral pH. Its replication was significantly inhibited by lysosomotropic agents, and it was highly neuroattenuated in vivo. In contrast, the recombinant expressing spike with L1114R alone mediated cell-to-cell fusion at neutral pH and replicated efficiently despite the presence of lysosomotropic agents; however, it still caused only subclinical morbidity and no mortality in animals. Thus, both recombinant viruses were highly attenuated and expressed viral antigen which was restricted to the olfactory bulbs and was markedly absent from other regions of the brains at 5 days postinfection. These data demonstrate that amino acid substitutions, in particular L1114R, within HR1 of the JHM spike reduced the ability of MHV to spread in the central nervous system. Furthermore, the requirements for low pH for fusion and viral entry are not prerequisites for the highly attenuated phenotype

Using discrete-event simulation to study the influence of log yard sorting on sawmill processing efficiency of small-diameter timber

A sawmill is similar to other manufacturing enterprises when it comes to making decisions, scheduling production and meeting customer demands. In order to help sawmills achieve their goals, and because there is such a high degree of variability in the raw material used in this industry, computer simulation has proven to be a very valuable tool to help improve productivity and processing efficiency. Raw material variability is expected to be an increasing issue in coming years due to an increase in small-diameter timber on the market resulting from the thinning of overstocked forest stands. These changes are expected to result in a significant decrease in production for mills that are not equipped to process this type of material. As a means of analyzing the influence of these changes, this thesis details the development and use of a discrete-event computer simulation model of the Warm Springs Forest Products Industries sawmill in Warm Springs, OR. This research is part of a larger project in which other improvement scenarios were studied (Salichon 2005). The simulation model was first used to identify some possible areas of improvement and to optimize the current overall process and production of the sawmill while operating with its current log distribution. The study identified a number of opportunities for improvement. It was demonstrated that increasing the unscrambler maximum capacity up to 800 boards resulted in an increase in piece count production ranging from 2.6 to 5.3%. The influence of machines downtimes as well as the influence of having a second operator assisting at the horizontal resaw were also investigated. Past studies have shown that log sorting is an essential condition to achieve high production in a sawmill. The simulation model was used to evaluate sorting strategies that would minimize the decrease in production resulting from introducing small-diameter timber (5 to 7 inches) into the log supply. Different small-diameter distributions were tried and different sorting solutions were tested for each of the log distributions. It was shown that the mill would suffer a decrease in piece count production ranging from 10.1 to 13.1% if their current two decks sort is retained. However, it was demonstrated that implementing a three decks sort would considerably reduce this drop in production to only 4.7 to 6.4%. Simulation has been shown to be a very valuable tool that sawmills can use to investigate production and other log supply issues. While piece count production was sufficient for analyzing current mill efficiency changes, the introduction of smaller diameter logs will also reduce the board feet per piece ratio. Due to the loss of the trimmer data during the test run, no information can be provided about board footage and thus the results and statistics in this research were based on piece count only. However, future work could be done with log breakdown models like BOF or SAW3D to determine board footage. Future research could also focus on studying the influence of the trimmer's downtimes on the unscrambler queue and other machine utilization rates as well as testing mathematical algorithms that will search for other optimized sorting and feeding strategies

A CFD Study on High‐Thrust Corrections for Blade Element Momentum Models

This paper presents a reanalysis of four axial‐flow rotor simulation datasets to study the relationship between thrust and axial induction factor. We concentrate on high‐thrust conditions and study variations in induction factor and loads across the span of the different rotor blades. The datasets consist of three different axial‐flow rotors operating at different tip‐speed ratios and, for one dataset, also at different blockage ratios. The reanalysis shows differences between the blade‐resolved CFD results and a widespread empirical turbulent wake model (TWM) used within blade element momentum (BEM) turbine models. These differences result in BEM models underestimating thrust and especially power for axial‐flow rotors operating in high‐thrust regimes. The accuracy of BEM model predictions are improved substantially by correcting this empirical TWM, producing better agreement with blade‐resolved CFD simulations for thrust and torque across most of the span of the blades of the three rotors. Additionally, the paper highlights deficiencies in tiploss modelling in common BEM implementations and highlights the impact of blockage on the relationship between thrust and axial induction factors

A Meta-Analysis on the Effects of Hydroxychloroquine on COVID-19.

Introduction Since December 2019, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has rapidly spread throughout the world with a large medical and economic impact. On March 12, 2020, the World Health Organization (WHO) classified SARS-CoV-2 as a pandemic. As a result of this worldwide public health crisis, politicians, elected officials, and healthcare professionals emergently began trialing hydroxychloroquine (HCQ) in efforts to treat and prevent the transmission of the virus. This meta-analysis was performed to assess the effects of HCQ on patients with COVID-19. Methods This meta-analysis adheres to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRIMA) guidelines. Selected articles published between December 2019 and July 2020 were found utilizing the following search engines: PubMed, Google Scholar, Cochrane Library, DisasterLit, Clinicaltrials.gov, Medrxiv, and Embase. Two independent physician reviewers screened eligible articles that met the inclusion and exclusion criteria of the analysis. The outcome measures analyzed were mortality rate, rate of disease progression/improvement, rate of disease severity, and adverse effects of treatment. Six out of 14 studies that met the study\u27s eligibility criteria were selected and further analyzed, with a total of 381 participants (n= 381). Conclusion From the studies analyzed, it was found that groups treated with HCQ had an overall mortality rate that was 2.5 times greater than that of the control group. HCQ treated patients had higher rates of adverse clinical outcomes and side effects compared with the control populations. Lastly, there was a 1.2 times higher rate of improvement in the group of HCQ treated patients with mild to moderate symptoms as compared to the control group

Constraining νΛ\nu \LambdaCDM with density-split clustering

The dependence of galaxy clustering on local density provides an effective method for extracting non-Gaussian information from galaxy surveys. The two-point correlation function (2PCF) provides a complete statistical description of a Gaussian density field. However, the late-time density field becomes non-Gaussian due to non-linear gravitational evolution and higher-order summary statistics are required to capture all of its cosmological information. Using a Fisher formalism based on halo catalogues from the Quijote simulations, we explore the possibility of retrieving this information using the density-split clustering (DS) method, which combines clustering statistics from regions of different environmental density. We show that DS provides more precise constraints on the parameters of the $\nu \Lambda$CDM model compared to the 2PCF, and we provide suggestions for where the extra information may come from. DS improves the constraints on the sum of neutrino masses by a factor of $8$ and by factors of 5, 3, 4, 6, and 6 for $\Omega_m$, $\Omega_b$, $h$, $n_s$, and $\sigma_8$, respectively. We compare DS statistics when the local density environment is estimated from the real or redshift-space positions of haloes. The inclusion of DS autocorrelation functions, in addition to the cross-correlation functions between DS environments and haloes, recovers most of the information that is lost when using the redshift-space halo positions to estimate the environment. We discuss the possibility of constructing simulation-based methods to model DS clustering statistics in different scenarios.Comment: Submitted to MNRAS. Source code for all figures in the paper is provided in the caption

Contrôle exécutif, cognition sociale, émotions et métacognition

Cette synthèse aborde la question de la cognition sociale (théorie de l’esprit en particulier), du traitement des émotions et de la métacognition dans une perspective de neuropsychologie clinique. Nous nous attardons sur les études examinant les relations qu’entretiennent ces différents aspects du comportement humain avec les fonctions exécutives et les structures frontales. Les résultats rapportés montrent que les liens potentiels entre la théorie de l’esprit et le fonctionnement exécutif font encore beaucoup débat, et que l’étude des relations entre théorie de l’esprit et lobe frontal mérite d’être affinée. Les lésions frontales perturbent le traitement des émotions, mais les relations entre perturbation des fonctions exécutives et troubles du traitement des émotions restent inexplorées. La métacognition a été peu étudiée chez les patients dysexécutifs par lésions frontales, si ce n’est au travers de quelques études sur la métamémoire qui montrent que les patients frontaux ont globalement tendance à surestimer leurs performances. Cette surestimation ne semble pas nécessairement procéder d’un déficit exécutif, d’une incapacité de jugement, ni d’une méconnaissance du fonctionnement mnésique normal et pathologique. Il ne s’agit pas non plus d’une difficulté d’utilisation de connaissances. De plus, les différentes mesures métamnésiques obtenues chez les patients frontaux corrèlent peu entre elles, indiquant qu’elles engagent probablement des processus du contrôle métamnésique relativement indépendants qu’il conviendrait de spécifier. Enfin, il faudra aussi vérifier, avec des malades porteurs de lésions frontales et/ou de syndromes dysexécutifs, les propositions théoriques les plus récentes voulant que les concepts de théorie de l’esprit et de métacognition soient finalement assez proches

Recombinant human erythropoietin in the treatment of chemotherapy-induced anemia and prevention of transfusion requirement associated with solid tumors: A randomized, controlled study

Background: Anemia is a common side effect of anticancer chemotherapy. Blood transfusion, previously the only available treatment for chemotherapy-induced anemia, may result insome clinical or subclinical adverse effects in the recipients. Recombinant human erythropoietin (rhEPO) provides a new treatment modality for chemotherapy-induced anemia. Patients and methods: To evaluate the effect of rhEPO onthe need for blood transfusions and on hemoglobin (Hb)concentrations, 227 patients with solid tumors and chemotherapy-induced anemia were enrolled in a randomized, controlled, clinical trial. Of 189 patients evaluable for efficacy, 101 received 5000 IU rhEPO daily s.c, while 88 patients received no treatment during the 12-week controlled phase of the study. Results: The results demonstrate a statistically significant reduction in the need for blood transfusions (28% vs. 42%, P = 0.028) and in the mean volume of packed red blood cells transfused (152 ml vs. 190 ml, p = 0.044) in patients treated with rhEPO compared to untreated controls. This effect was even more pronounced in patients receiving platinum-based chemotherapy (26% vs. 45%, % 0.038). During the controlled treatment phase, the median Hb values increased in the rhEPO patients while remaining unchanged in the control group. The response was seen in all tumor types. Conclusions: RhEPO administration at a dose of 5000 IU daily s.c. increases hemoglobin levels and reduces transfusionrequirements in chemotherapy-induced anemia, especially during platinum-based chemotherap