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Increased ventilator use during the COVID-19 pandemic resurrected persistent questions regarding mechanical ventilation including the difference between physiological and artificial breathing induced by ventilators (i.e., positive- versus negative-pressure ventilation, PPV vs NPV). To address this controversy, we compare murine specimens subjected to PPV and NPV in ex vivo quasi-static loading and quantify pulmonary mechanics via measures of quasi-static and dynamic compliances, transpulmonary pressure, and energetics when varying inflation frequency and volume. Each investigated mechanical parameter yields instance(s) of significant variability between ventilation modes. Most notably, inflation compliance, percent relaxation, and peak pressure are found to be consistently dependent on the ventilation mode. Maximum inflation volume and frequency note varied dependencies contingent on the ventilation mode. Contradictory to limited previous clinical investigations of oxygenation and end-inspiratory measures, the mechanics-focused comprehensive findings presented here indicate lung properties are dependent on loading mode, and importantly, these dependencies differ between smaller versus larger mammalian species despite identical custom-designed PPV/NPV ventilator usage. Results indicate that past contradictory findings regarding ventilation mode comparisons in the field may be linked to the chosen animal model. Understanding the differing fundamental mechanics between PPV and NPV may provide insights for improving ventilation strategies and design to prevent associated lung injuries. [ABSTRACT FROM AUTHOR]

We present temperature maps derived from number density retrievals of carbon dioxide (CO2) for the upper mesosphere and lower thermosphere of Mars using limb observations from the Imaging Ultraviolet Spectrograph (IUVS) aboard NASA's Mars Atmosphere and Volatile EvolutioN (MAVEN) spacecraft. We retrieve CO2 densities using O(1S) metastable atoms that radiatively relax by emitting photons at 297.2 nm, producing a double‐peaked emission profile detectable by IUVS. Retrieved CO2 densities are used to derive altitude profiles of temperature as a function of latitude, longitude, local time, season, dust activity, and solar activity. CO2 density and temperature profiles retrieved using the O I 297.2 nm emission feature presented herein extend previous IUVS retrievals from 130–170 km down to 80 km. We validate retrieved CO2 densities and derived temperatures using coincident measurements and corresponding data products produced by MAVEN IUVS, as available. Analysis of this comprehensive data set, which spans Mars years 32–36, shows (a) a consistently well‐defined mesopause at approximately 120 km, (b) warming at high pressures (typically below ∼100 km) for a variety of geophysical conditions, (c) asymmetry in temperatures at dawn and dusk with respect to latitude during different seasons (warmer temperatures at dawn during northern hemisphere autumn/winter and cooler temperatures at dusk during spring/summer), and (d) longitudinal waves with a dominant wave‐3 component in both the upper mesosphere and lower thermosphere, with lower (80–90 km) and upper (135–145 km) atmospheric waves about 65° out of phase. Plain Language Summary: We show the first O I 297.2 nm emission‐derived temperature profiles extending from 80 to 150 km in the atmosphere of Mars obtained from observations by the Imaging Ultraviolet Spectrograph onboard NASA's Mars Atmosphere and Volatile EvolutioN spacecraft. This new analysis enables us to bridge the gap and improve our understanding of the coupling that occurs between the middle and upper atmospheres of Mars. Our analysis has revealed thermal variability in the Martian atmosphere with respect to latitude, longitude, local time, season, dust activity, and solar activity. As suggested by previous studies, waves generated in the lower atmosphere propagate to the upper atmosphere, coupling the atmospheric layers, and produce fluctuations in density (up to 40% locally) that can affect the background atmospheric temperature, which is a key parameter driving thermal escape of atomic hydrogen. The density and temperature data presented here provide an important but heretofore missing source of information that is needed to directly link weather and waves in the lower atmosphere to perturbations in composition and temperature in the upper atmosphere. Key Points: Our analysis reveals a consistently well‐defined mesopause at approximately 120 kmWe observe an asymmetry in temperatures at dawn and dusk with respect to latitude during different seasonsLongitudinal waves with dominant wave‐3 component are characterized in both the upper mesosphere and lower thermosphere [ABSTRACT FROM AUTHOR]

The recent onset of the COVID-19 pandemic has had a pervasive impact on all economies and indeed housing markets. This research investigates the regional impact of the pandemic on the Northern Ireland housing market and provides a unique opportunity to measure short-term reactions to epidemic shocks. Applying a unique dataset, the research measures whether price switching effects are evident as a consequence of the epidemic, and to what extent. In order to achieve this, the research applies spatial lag models to account for the effect of COVID-19 on housing market pricing behaviour. The findings show that the autocorrelation of house prices increased after COVID-19, revealing price persistence driven by behavioural changes. The results further show that a price divergent effect is observable, with the detached sector 'leading' the price changes. This price divergence is also apparent for rural dwellings and for neighbourhoods with higher socio-economic standing making them more resistant to the outbreak of COVID-19. This is an important finding as it reveals that epidemics of this nature impact upon housing markets in a heterogeneous way in the short-term, with a clear premium observed for larger housing in healthier and wealthier areas, which may serve to reinforce housing market inequalities. [ABSTRACT FROM AUTHOR]

The main purpose of this paper is to design an innovative ship handling simulation program by combining the development of Quest3D software and the Google earth harbor terrain software. The paper describes the usage of the Google earth program to retrieve the latitude and longitude elevation, through GIS conversion and 3D graphical model to generate the Quest 3D harbor construction blueprint. Projectors display the image with build-in formula calculated angle settings to achieve a better perspective for the projectors installation. A 3D virtual reality scene was built by using the Maya Model, and then we overlap with the harbor module to complete the famous world ports. The results will be tested in the ship handling simulator machine at the 3D virtual reality software development laboratory. [ABSTRACT FROM AUTHOR]

The ε(0,0) (D [sup 2]Σ[sup +]–X [sup 2]Π[sub r]) band of NO has been recorded by using a vacuum ultraviolet Fourier transform spectrometer from Imperial College, London, with synchrotron radiation at the Photon Factory, KEK, Japan, as a continuum light source. Analysis of the ε(0,0) band provides accurate rotational line positions and term values as well as the photoabsorption cross sections. Molecular constants of the v=0 level of the D [sup 2]Σ state have been determined as T[sub 0]=53 291.10±0.10 cm[sup -1], B[sub 0]=1.991 07±0.000 05 cm[sup -1], and D[sub 0]=(6.6±0.1)×10[sup -6] cm[sup -1]. Accurate rotational line strengths have also been obtained and the sum of the line strengths for all rotational lines is determined as 2.18×10[sup -15] cm[sup 2] cm[sup -1]. The band oscillator strength of the ε(0,0) band is determined to be (2.47±0.12)×10[sup -3]. © 2003 American Institute of Physics. [ABSTRACT FROM AUTHOR]

The β(6,0) (B [sup 2]Π[sub r]–X [sup 2]Π[sub r]) and γ(3,0) (A [sup 2]Σ[sup +]–X [sup 2]Π[sub r]) bands of NO have been recorded using a vacuum ultraviolet Fourier transform spectrometer with synchrotron radiation as light source. The analysis of the β(6,0) and γ(3,0) bands of NO provides accurate rotational line positions and term values. Molecular constants of the v=6 level of the B [sup 2]Π[sub r] and v=3 level of the A [sup 2]Σ[sup +] have been determined. Accurate rotational line strengths have also been obtained. The band oscillator strength of the β(6,0) and γ(3,0) bands are determined to be 0.48×10[sup -4] and 2.69×10[sup -4], respectively. © 2002 American Institute of Physics. [ABSTRACT FROM AUTHOR]

A general formula is found to predict thermoluminescence emission over a wide range of heating profiles. This is particularly useful for rapid laser heating which generates very nonlinear temperature-time profiles. Special cases of the general formula are considered for power-law and logarithmic temperature-time curves. The results compare well to previous CO[sub 2] laser heated thermoluminescence experiments. The agreement between theory and experiment extends over several orders of magnitude change in the heating rate. © 2001 American Institute of Physics. [ABSTRACT FROM AUTHOR]

The dynamics of debris in a buffer gas after ejection from the solid target during laser-plasma soft x-ray generation is studied. Analytical formulas for the flight range of cylindrical and spherical debris are derived using the incompressible flow theory. The validity range of the formulas and the related error margins are discussed. Finally, the flight range formula for spherical particles is extended to two times the Mach number at the expenses of a somewhat higher error margin (up to 25%). © 2001 American Institute of Physics. [ABSTRACT FROM AUTHOR]

We have measured the 30 and 100 eV far ultraviolet (FUV) emission cross sections of the optically allowed Fourth Positive Group (4PG) band system (A1Π → X1Σ+) of CO and the optically forbidden O (5So → 3P) 135.6 nm atomic transition by electron‐impact‐induced‐fluorescence of CO and CO2. We present a model excitation cross section from threshold to high energy for the A1Π state, including cascade by electron impact on CO. The A1Π state is perturbed by triplet states leading to an extended FUV glow from electron excitation of CO. We derive a model FUV spectrum of the 4PG band system from dissociative excitation of CO2, an important process observed on Mars and Venus. Our unique experimental setup consists of a large vacuum chamber housing an electron gun system and the Mars Atmosphere and Volatile EvolutioN (MAVEN) mission Imaging Ultraviolet Spectrograph optical engineering unit, operating in the FUV (110–170 nm). The determination of the total O i (5So) at 135.6 nm emission cross section is accomplished by measuring the cylindrical glow pattern of the metastable emission from electron impact by imaging the glow intensity about the electron beam from nominally zero to ~400 mm distance from the electron beam. The study of the glow pattern of O i (135.6 nm) from dissociative excitation of CO and CO2 indicates that the O i (5So) state has a kinetic energy of ~1 eV by modeling the radial glow pattern with the published lifetime of 180 μs for the O i (5So) state. Plain Language Summary: Both Mars and Venus have upper atmospheres that are similar in composition: mostly CO2, CO, and N2 are dominant molecular gases, with nearly identical UV spectra. The modeling studies of atmospheric UV emissions cannot presently be accurately conducted to the same accuracy as the planetary UV measurements, which avail themselves with state‐of‐the‐art calibrated spectrographs. This dichotomy in accuracy between planetary observation and model occurs because the atomic and molecular emission cross sections with uncertainties of certain transitions are greater than 100%. Furthermore, the analysis is complicated by the spectral blending of the various emissions of the low‐resolution spectral spaceborne instruments. We present in this paper a UV laboratory instrument unique in the world at the University of Colorado that can measure for the first time the excitation mechanisms with accurate emission cross sections of both allowed and optically forbidden transitions that are occurring in a planetary atmosphere. Key Points: We measured 30 and 100 eV emission cross sections of Fourth Positive band system of CO and O i (135.6 nm) from electron impact on CO and CO2We conducted a laboratory experiment measuring single‐scattering electron‐impact‐induced‐fluorescence FUV spectra from excitation of CO and CO2Fragment kinetic energy measurement for O i (5So) atoms found to be around ~1 eV from both CO and CO2 molecular dissociation [ABSTRACT FROM AUTHOR]

Background A community of practice (cop) is formally defined as a group of people who share a concern or a passion for something they do and who learn how to do it better as they interact regularly. Communities of practice represent a promising approach for improving cancer care outcomes. However, little research is available to guide the development of oncology cops. In 2015, our urban community hospital launched an oncology cop, with the goals of decreasing barriers to access, fostering collaboration, and improving practitioner knowledge of guidelines and services in cancer care. Here, we share insights from a qualitative analysis of feedback from participants in our cop. The objective of the project was to identify participant perspectives about preferred cop features, with a view to improving the quality of our community hospital's oncology cop. Methods After 5 in-person meetings of our oncology cop, participants were surveyed about what the cop should start, stop, and continue doing. Qualitative methods were used to analyze the feedback. Results The survey collected 250 comments from 117 unique cop participants, including family physicians, specialist physicians, nurses, and allied health care practitioners. Analysis identified participant perspectives about the key features of the cop and avenues for improvement across four themes: supporting knowledge exchange, identifying and addressing practice gaps, enhancing interprofessional collaboration, and fostering a culture of partnership. Conclusions Based on the results, we identified several considerations that could be helpful in improving our cop. Our findings might help guide the development of oncology cops at other institutions. [ABSTRACT FROM AUTHOR]

Background Communities of practice (cops) have been shown to be effective models for achieving quality outcomes in health care. Objective Here, we describe the application of the cop model to the Canadian oncology context. Methods We established an oncology cop at our urban community hospital and its networks. Goals were to decrease barriers to access, foster collaboration, and improve knowledge of guidelines in cancer care. We hosted 6 in-person multidisciplinary meetings, focusing on screening, diagnosis, and management of common solid tumours. Health care providers affiliated with our hospital were invited to attend and to complete post-meeting surveys. Likert scales assessed whether cop goals were realized. Results Meetings attracted a mean of 57 attendees (range: 48-65 attendees), with a mean of 84% completing the surveys and consenting to the analysis. Attendees included family physicians (mean: 41%), specialist physicians (mean: 24%), nurses (mean: 10%), and allied health care providers (mean: 22%). Repeat attendance increased during the series, with 85% of attendees at the final meeting having attended 1 or more prior meetings. Across the series, most participants agreed or strongly agreed that the cop reduced barriers (mean: 76.0% ± 7.9%) and improved access to cancer care services (mean: 82.4% ± 8.1%) and subject matter experts (mean: 91.7% ± 4.2%); fostered teamwork (mean: 84.5% ± 6.8%) and a culture of collaboration (mean: 94.8% ± 4.2%); improved knowledge of cancer care services (mean: 93.3% ± 4.8%), standards of practice (mean: 92.3% ± 3.1%), and quality indicators (mean: 77.5% ± 6.3%); and improved cancer-related practice (mean: 88.8% ± 4.6%) and satisfaction in caring for cancer patients (mean: 82.9% ± 6.8%). Participant feedback carried a potential for bias. Conclusions We demonstrated the feasibility of oncology cops and found that participants perceived their value in reducing barriers to access, fostering collaboration, and improving knowledge of guidelines in cancer care. [ABSTRACT FROM AUTHOR]

The goal of this contribution is to show the capabilities of relatively fast computation techniques which can be advantageously used in design optimization procedures of electrical machines. The computation of cogging torque, for rotating machines, and force, for linear machines, being very sensitive to the accuracy of used models, its estimation is then used as an indicator for the efficacy and correctness of these techniques. A finite-element (FE) model will be used as a reference model. The first technique is based on a reluctance network (RN) generated from a mesh of studied structure. The second technique consists of coupling RNs obtained from a mesh of some parts of studied structure and an analytical model of magnetic field in other parts. These techniques are used for the modeling of a linear tubular flux-switching permanent magnet (LTFSPM) machine. LTFSPM machines are relatively complicated to model, and their modeling using these two techniques has never been reported yet in the scientific literature. The two models are both validated by comparisons with FE analyses. [ABSTRACT FROM AUTHOR]

Focuses on a study conduted using simplified kinetic models to investigate the mechanism of negative differential conductivity (NDC) in an electron-beam sustained gas discharge of pure xenon (Xe). Calculation of the drift velocity of electrons in Xe; What model calculations involves; Definition of NDC; Discussion on the influence of the uncertainty in the momentum transfer cross sections and the small impurity of Xe on NDC observation.

Presents information on a study which described the use of thermal deposition of silicon[sub2]hydrogen[sub6] in a hydrogen or helium flow for the deposition of alpha-silicon:hydrogen films on Corning 7059 glass substrates. Deposition of the films; Electrical conductivity of the films.

Abstract: We report the detection of bright aurora spanning Mars' nightside during the space weather event occurring in September 2017. The phenomenon was similar to diffuse aurora detected previously at Mars, but 25 times brighter and detectable over the entire visible nightside. The observations were made with the Imaging UltraViolet Spectrograph, a remote sensing instrument on the Mars Atmosphere and Volatile EvolutioN spacecraft orbiting Mars. Images show that the emission was brightest around the limb of the planet, with a fairly uniform faint glow against the disk itself. Spectra identified four molecular emissions associated with aurora, and limb scans show the emission originated from an altitude of ~60 km in the atmosphere. Both are consistent with very high energy particle precipitation. The auroral brightening peaked around 13 September, when the flux of solar energetic electrons and protons both peaked. During the declining phase of the event, faint but statistically significant auroral emissions briefly appeared against the disk of the planet in the form of narrow wisps and small patches. These features are approximately aligned with predicted open field lines in the region of strong crustal magnetic fields in Mars' southern hemisphere. [ABSTRACT FROM AUTHOR]

Abstract: We report the response of the Martian upper atmosphere to a strong X‐class flare on 10 September 2017 as observed by the Imaging Ultraviolet Spectrograph (IUVS) instrument aboard the Mars Atmosphere Volatile EvolutioN (MAVEN) mission. The solar flare peaked at 16:24 hr UT, and IUVS dayglow observations were taken about an hour after the flare peak. Retrieved temperatures from IUVS dayglow observations show a significant increase during the flare orbit, with a mean value of ∼270 K and a maximum value of ∼310 K. The retrieved temperatures during the flare orbit also show a strong latitudinal gradient, indicating that the flare‐induced heating is limited between low and middle latitudes. During this event IUVS observed an ∼70% increase in the observed brightness of CO 2 + ultraviolet doublet and CO Cameron band emission at 90 km, where high‐energy photons (< 10 nm) deposit most of their energy. [ABSTRACT FROM AUTHOR]

The Ufm1 conjugation system is a novel ubiquitin-like modification system, consisting of Ufm1, Uba5 (E1), Ufc1 (E2) and poorly characterized E3 ligase(s). RCAD/Ufl1 (also known as KIAA0776, NLBP and Maxer) was reported to function as a Ufm1 E3 ligase in ufmylation (Ufm1-mediated conjugation) of DDRGK1 and ASC1 proteins. It has also been implicated in estrogen receptor signaling, unfolded protein response (UPR) and neurodegeneration, yet its physiological function remains completely unknown. In this study, we report that RCAD/Ufl1 is essential for embryonic development, hematopoietic stem cell (HSC) survival and erythroid differentiation. Both germ-line and somatic deletion of RCAD/Ufl1 impaired hematopoietic development, resulting in severe anemia, cytopenia and ultimately animal death. Depletion of RCAD/Ufl1 caused elevated endoplasmic reticulum stress and evoked UPR in bone marrow cells. In addition, loss of RCAD/Ufl1 blocked autophagic degradation, increased mitochondrial mass and reactive oxygen species, and led to DNA damage response, p53 activation and enhanced cell death of HSCs. Collectively, our study provides the first genetic evidence for the indispensable role of RCAD/Ufl1 in murine hematopoiesis and development. The finding of RCAD/Ufl1 as a key regulator of cellular stress response sheds a light into the role of a novel protein network including RCAD/Ufl1 and its associated proteins in regulating cellular homeostasis. [ABSTRACT FROM AUTHOR]

The present study adopts a volume-of-solid (VOS)-based immersed-boundary method (IBM) to simulate viscous incompressible flows interacting with moving solids using a numerical model based on the Navier-Stokes equations. The flow equations, with velocity–pressure variables, are discretized by a finite–element method on a nonuniform Cartesian grid, with the solutions obtained using a decoupled numerical scheme. Geometries featuring flexible solid obstacles in the flow are embedded in the Cartesian grid, with special treatments inside the embedded cell to ensure the accuracy of the solutions in the cut cells. In order to satisfy the no-slip condition of the body surface, a volume fraction is estimated to calculate the discretized body force inside the cut cell. More reasonable results for flow problems, including flows past a non-control/control circular cylinder and two cylinders moving against each other, are obtained by the present method. The time histories of drag and lift coefficients, as well as the vortex shedding frequencies, are extensively examined to demonstrate that the proposed method can be suitably combined with the fractional-step algorithm. Moreover, the temporal variations of velocity and vorticity fields are presented to demonstrate the capability of the present formulation in solving flow problems involving complex geometries, and the significance of the solid body forces on the flows. [ABSTRACT FROM PUBLISHER]

Upregulated expression of nucleolar GTPase nucleostemin (NS) has been associated with increased cellular proliferation potential and tumor malignancy during cancer development. Recent reports attribute the growth regulatory effects of NS protein to its role in facilitating ribosome production. However, the oncogenic potential of NS remains unclear, as imbalanced levels of NS have been reported to exert growth inhibitory effect by modulating p53 tumor-suppressor activity. It also remains in questions if aberrant NS levels might have a p53-independent role in regulation of cell proliferation and growth. In this study, we performed affinity purification and mass spectrometry analysis to explore protein-protein interactions influencing NS growth regulatory properties independently of p53 tumor suppressor. We identified the alternative reading frame (ARF) protein as a key protein associating with NS and further verified the interaction through in vitro and in vivo assays. We demonstrated that NS is able to regulate cell cycle progression by regulating the stability of the ARF tumor suppressor. Furthermore, overexpression of NS suppressed ARF polyubiquitination by its E3 ligase Ubiquitin Ligase for ARF and elongated its half-life, whereas knockdown of NS led to the decrease of ARF levels. Also, we found that NS can enhance NPM stabilization of ARF. Thus, we propose that in the absence of p53, ARF can be stabilized by NS and nucleophosmin to serve as an alternative tumor-suppressor surveillance, preventing potential cellular transformation resulting from the growth-inducing effects of NS overexpression. [ABSTRACT FROM AUTHOR]