Next Generation Advanced Video Guidance Sensor Development and Test

The Advanced Video Guidance Sensor (AVGS) was the primary docking sensor for the Orbital Express mission. The sensor performed extremely well during the mission, and the technology has been proven on orbit in other flights too. Parts obsolescence issues prevented the construction of more AVGS units, so the next generation of sensor was designed with current parts and updated to support future programs. The Next Generation Advanced Video Guidance Sensor (NGAVGS) has been tested as a breadboard, two different brassboard units, and a prototype. The testing revealed further improvements that could be made and demonstrated capability beyond that ever demonstrated by the sensor on orbit. This paper presents some of the sensor history, parts obsolescence issues, radiation concerns, and software improvements to the NGAVGS. In addition, some of the testing and test results are presented. The NGAVGS has shown that it will meet the general requirements for any space proximity operations or docking need

Wilkes Station Glaciology, 1958.

Submitted to the U.S. National Committee for the IGY, National Academy of Sciences, in partial fulfillment of IGY Project Number 4.10 - NSF Grant No. Y/4.10/285.This report contains the major part of the glaciological data collected by the 1958 wintering-over party at Wilkes Station. In several cases the measurements reported here are a continuation of those of 1957, and no attempt has been made to duplicate basic information already published in the data report for that year (Cameron et al., 1959). In conformity with IGY procedure, these first reports have been limited to data and to the information necessary for their analysis. A preliminary summary of the glaciological work at Wilkes Station in 1957 and 1958 has been published in the Journal of Glaciology (Hollin and Cameron, 1961) and is recommended as an introduction to this report.National Science Foundation Grant No. Y/4.10/285

Characterization of Kupffer cells in livers of developing mice

Abstract Background Kupffer cells are well known macrophages of the liver, however, the developmental characteristics of Kupffer cells in mice are not well understood. To clarify this matter, the characteristics of Kupffer macrophages in normal developing mouse liver were studied using light microscopy and immunocytochemistry. Methods Sections of liver tissue from early postnatal mice were prepared using immunocytochemical techniques. The Kupffer cells were identified by their immunoreactivity to the F4/80 antibody, whereas endothelial cells were labelled with the CD-34 antibody. In addition, Kupffer cells and endothelial cells were labelled by systemically injected fluorescently labelled latex microspheres. Tissue slices were examined by fluorescence microscopy. Results Intravenous or intraperitonal injections of microspheres yielded similar patterns of liver cell labelling. The F4/80 positive Kupffer cells were labelled with both large (0.2 μm) and small (0.02 μm) diameter microspheres, while endothelial cells were labelled only with the smaller diameter microspheres. Microsphere labelling of Kupffer cells appeared stable for at least 6 weeks. Cells immunoreactive for F4/80 were identified as early as postnatal day 0, and these cells also displayed uptake of microspheres. Numbers of F4/80 Kupffer cells, relative to numbers of albumin positive hepatocytes, did not show a significant trend over the first 2 postnatal weeks. Conclusions Kupffer cells of the developing mouse liver appear quite similar to those of other mammalian species, confirming that the mouse presents a useful animal model for studies of liver macrophage developmental structure and function

Risk of COVID-19 death in adults who received booster COVID-19 vaccinations in England

The emergence of the COVID-19 vaccination has been critical in changing the course of the COVID-19 pandemic. To ensure protection remains high in vulnerable groups booster vaccinations in the UK have been targeted based on age and clinical vulnerabilities. We undertook a national retrospective cohort study using data from the 2021 Census linked to electronic health records. We fitted cause-specific Cox models to examine the association between health conditions and the risk of COVID-19 death and all-other-cause death for adults aged 50-100-years in England vaccinated with a booster in autumn 2022. Here we show, having learning disabilities or Down Syndrome (hazard ratio=5.07;95% confidence interval=3.69-6.98), pulmonary hypertension or fibrosis (2.88;2.43-3.40), motor neuron disease, multiple sclerosis, myasthenia or Huntington’s disease (2.94, 1.82-4.74), cancer of blood and bone marrow (3.11;2.72-3.56), Parkinson’s disease (2.74;2.34-3.20), lung or oral cancer (2.57;2.04 to 3.24), dementia (2.64;2.46 to 2.83) or liver cirrhosis (2.65;1.95 to 3.59) was associated with an increased risk of COVID-19 death. Individuals with cancer of the blood or bone marrow, chronic kidney disease, cystic fibrosis, pulmonary hypotension or fibrosis, or rheumatoid arthritis or systemic lupus erythematosus had a significantly higher risk of COVID-19 death relative to other causes of death compared with individuals who did not have diagnoses. Policy makers should continue to priorities vulnerable groups for subsequent COVID-19 booster doses to minimise the risk of COVID-19 death

A methodology for the capture and analysis of hybrid data: a case study of program debugging

No description supplie

Reuters Institute Digital News Report 2023

Le ‘Reuters Institute’ (University of Oxford) annonce la mise en ligne de son rapport « Digital News Report 2023 » sur la consommation d’informations numériques auprès de plus de 93 000 consommateurs d’informations en ligne sur 46 pays

RNA polymerase II stalling promotes nucleosome occlusion and pTEFb recruitment to drive immortalization by Epstein-Barr virus

Epstein-Barr virus (EBV) immortalizes resting B-cells and is a key etiologic agent in the development of numerous cancers. The essential EBV-encoded protein EBNA 2 activates the viral C promoter (Cp) producing a message of ~120 kb that is differentially spliced to encode all EBNAs required for immortalization. We have previously shown that EBNA 2-activated transcription is dependent on the activity of the RNA polymerase II (pol II) C-terminal domain (CTD) kinase pTEFb (CDK9/cyclin T1). We now demonstrate that Cp, in contrast to two shorter EBNA 2-activated viral genes (LMP 1 and 2A), displays high levels of promoter-proximally stalled pol II despite being constitutively active. Consistent with pol II stalling, we detect considerable pausing complex (NELF/DSIF) association with Cp. Significantly, we observe substantial Cp-specific pTEFb recruitment that stimulates high-level pol II CTD serine 2 phosphorylation at distal regions (up to +75 kb), promoting elongation. We reveal that Cp-specific pol II accumulation is directed by DNA sequences unfavourable for nucleosome assembly that increase TBP access and pol II recruitment. Stalled pol II then maintains Cp nucleosome depletion. Our data indicate that pTEFb is recruited to Cp by the bromodomain protein Brd4, with polymerase stalling facilitating stable association of pTEFb. The Brd4 inhibitor JQ1 and the pTEFb inhibitors DRB and Flavopiridol significantly reduce Cp, but not LMP1 transcript production indicating that Brd4 and pTEFb are required for Cp transcription. Taken together our data indicate that pol II stalling at Cp promotes transcription of essential immortalizing genes during EBV infection by (i) preventing promoter-proximal nucleosome assembly and ii) necessitating the recruitment of pTEFb thereby maintaining serine 2 CTD phosphorylation at distal regions

Implementation of U.K. Earth system models for CMIP6

We describe the scientific and technical implementation of two models for a core set of experiments contributing to the sixth phase of the Coupled Model Intercomparison Project (CMIP6). The models used are the physical atmosphere-land-ocean-sea ice model HadGEM3-GC3.1 and the Earth system model UKESM1 which adds a carbon-nitrogen cycle and atmospheric chemistry to HadGEM3-GC3.1. The model results are constrained by the external boundary conditions (forcing data) and initial conditions.We outline the scientific rationale and assumptions made in specifying these. Notable details of the implementation include an ozone redistribution scheme for prescribed ozone simulations (HadGEM3-GC3.1) to avoid inconsistencies with the model's thermal tropopause, and land use change in dynamic vegetation simulations (UKESM1) whose influence will be subject to potential biases in the simulation of background natural vegetation.We discuss the implications of these decisions for interpretation of the simulation results. These simulations are expensive in terms of human and CPU resources and will underpin many further experiments; we describe some of the technical steps taken to ensure their scientific robustness and reproducibility