1,045 research outputs found
A DEVSECOPS APPROACH FOR DEVELOPING AND DEPLOYING CONTAINERIZED CLOUD-BASED SOFTWARE ON SUBMARINES
There are unique challenges for using secure cloud services in disconnected resource-constrained environments and with controlled data. To address those challenges, this thesis introduces a tactical-edge platform-as-a-service (PaaS) solution with a declarative-delivery method for submarine Consolidated Afloat Network Enterprise Services (CANES) operating systems. The PaaS is adapted from the Department of Defense’s Big Bang core elements for submarine-focused outcomes. Using the Team Submarine Project Blue initiative as a case study, this thesis consists of a feasibility study for running containerized applications on different submarine-compatible baselines and applying a prototype declarative software-delivery method called ZARF. We demonstrated the feasibility of using ZARF for packaging and automated deployment of the Project Blue PaaS and its software to the submarine CANES infrastructure. This research culminated in successful integration tests on a current and future submarine hardware and software baseline. The thesis documents the execution of the research, lessons learned, and recommendations for the Navy’s path forward for development of secure software and declarative deployment in air-gapped environments.Outstanding ThesisLieutenant, United States NavyApproved for public release. Distribution is unlimited
The Viking rocket: A memoir
The development and testing of the Viking rocket series is reviewed. These twelve sounding rockets were launched from 1949 to 1954
Effect of Buffer Layer and III/V Ratio on the Surface Morphology of GaN Grown by MBE
The surface morphology of GaN is observed by atomic force microscopy for growth on GaN and AlN buffer layers and as a function of III/V flux ratio. Films are grown on sapphire substrates by molecular beam epitaxy using a radio frequency nitrogen plasma source. Growth using GaN buffer layers leads to N-polar films, with surfaces strongly dependent on the flux conditions used. Flat surfaces can be obtained by growing as Ga-rich as possible, although Ga droplets tend to form. Ga-polar films can be grown on AlN buffer layers, with the surface morphology determined by the conditions of buffer layer deposition as well as the III/V ratio for growth of the GaN layer. Near-stoichiometric buffer layer growth conditions appear to support the flattest surfaces in this case. Three defect types are typically observed in GaN films on AlN buffers, including large and small pits and "loop" defects. It is possible to produce surfaces free from large pit defects by growing thicker films under more Ga-rich conditions. In such cases the surface roughness can be reduced to less than 1 nm RMS
Step-wedge cluster-randomised community-based trials: An application to the study of the impact of community health insurance
This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.BACKGROUND: We describe a step-wedge cluster-randomised community-based trial which has been conducted since 2003 to accompany the implementation of a community health insurance (CHI) scheme in West Africa. The trial aims at overcoming the paucity of evidence-based information on the impact of CHI. Impact is defined in terms of changes in health service utilisation and household protection against the cost of illness. Our exclusive focus on the description and discussion of the methods is justified by the fact that the study relies on a methodology previously applied in the field of disease control, but never in the field of health financing. METHODS: First, we clarify how clusters were defined both in respect of statistical considerations and of local geographical and socio-cultural concerns. Second, we illustrate how households within clusters were sampled. Third, we expound the data collection process and the survey instruments. Finally, we outline the statistical tools to be applied to estimate the impact of CHI. CONCLUSION: We discuss all design choices both in relation to methodological considerations and to specific ethical and organisational concerns faced in the field. On the basis of the appraisal of our experience, we postulate that conducting relatively sophisticated trials (such as our step-wedge cluster-randomised community-based trial) aimed at generating sound public health evidence, is both feasible and valuable also in low income settings. Our work shows that if accurately designed in conjunction with local health authorities, such trials have the potential to generate sound scientific evidence and do not hinder, but at times even facilitate, the implementation of complex health interventions such as CHI
Nesting Common Eider (Somateria mollissima) Population Quintuples in Northwest Greenland
Common eider (Somateria mollissima) populations in Greenland severely declined throughout the 20th century. As a result, in 2001, harvest regulations were changed and the length of the hunting season was reduced. Recent data suggest that these changes have been successful, and population regrowth is occurring. In the Avanersuaq District, northwest Greenland, only one systematic survey quantifying the number of nesting eiders had previously been conducted, in 1997 and 1998. Although this district had historically been identified as having the largest number of breeding eiders in Greenland, the 1997–98 survey results showed a relatively small estimated population of 5000 pairs. However, it is not known to what extent changes in hunting regulations have affected nesting abundance in this area. Therefore, the Avanersuaq District was systematically resurveyed during the 2009 breeding season, approximately 11 years after the previous survey. These results showed that the population had increased to 5.4 times its 1997–98 size, with an annual compounded growth rate of 15.3%. On a single island, nearly 4500 active nests were observed. Five islands had more than 2600 nests each and comprised 75% of the total nests counted. Along with historical information to account for additional nesting habitat not surveyed, the observed population growth rate from this study suggests that the overall Avanersuaq common eider breeding population size ranges from 25 000 to 30 000 pairs, or roughly half of the total estimated West Greenland breeding population. Despite the significance of the Avanersuaq District as a breeding area for common eiders, we have only limited information about this population. The effects of recent extensions of the hunting season on this population are also unknown, and the only wintering location information is based on a few individuals banded in the 1920s and 1940s. Additional research on migratory movements is suggested before any further changes are made to hunting regulations.Au cours du XXe siècle, les populations d’eiders à duvet (Somateria mollissima) ont connu un déclin considérable au Groenland. C’est pourquoi en 2001, le règlement relatif à la chasse a été modifié et la saison de chasse a été raccourcie. Selon des données récentes, ces changements ont porté fruits en ce sens que la population s’est accrue. Dans le district d’Avanersuaq, dans le nord-ouest du Groenland, seulement un relevé systématique ayant pour but de quantifier le nombre d’eiders nicheurs a été fait, et c’était en 1997-1998. Bien qu’au fil des ans, ce district a compté le plus grand nombre d’eiders reproducteurs du Groenland, le relevé de 1997-1998 avait établi que la population était relativement petite, avec une estimation de 5 000 paires. On ne sait toutefois pas dans quelle mesure la modification du règlement sur la chasse a eu des effets sur l’abondance d’eiders nichant dans la région. Par conséquent, le district d’Avarsuaq a systématiquement fait l’objet d’un autre relevé pendant la saison de reproduction de 2009, soit environ 11 ans après le relevé d’origine. Les résultats ont permis de constater que la population s’était accrue dans une mesure de 5,4 fois par rapport à sa taille de 1997-1998, ce qui correspondait à un taux d’accroissement annuel composé de 15,3 %. Sur une seule île, près de 4 500 nids actifs ont été observés. Cinq îles comptaient plus de 2 600 nids par île, ce qui représentait 75 % du nombre total de nids répertoriés. Jumelé aux données historiques tenant compte de l’habitat de nidification supplémentaire et non relevé, le taux d’accroissement de la population observé à partir de cette étude suggère que la taille de la population globale d’eiders à duvet nicheurs d’Avanersuaq varie de 25 000 à 30 000 paires, ce qui correspond à environ la moitié du total estimé de la population nicheuse de l’ouest du Groenland. Malgré l’importance que revêt le district d’Avanersuaq comme aire de reproduction de l’eider à duvet, nous ne possédons que des renseignements restreints au sujet de cette population. Les effets qu’aura le prolongement récent de la saison de chasse sur cette population sont également inconnus, et la seule information concernant la localisation de l’aire d’hivernage dont nous disposons a trait à quelques individus qui avaient été bagués dans les années 1920 et 1940. Par conséquent, il est suggéré de pousser les recherches relatives aux mouvements migratoires plus loin avant d’apporter d’autres changements au règlement de chasse
Genomic imbalances are confined to non-proliferating cells in paediatric patients with acute myeloid leukaemia and a normal or incomplete karyotype
Copyright @ 2011 Ballabio et al.Leukaemia is often associated with genetic alterations such as translocations, amplifications and deletions, and recurrent chromosome abnormalities are used as markers of diagnostic and prognostic relevance. However, a proportion of acute myeloid leukaemia (AML) cases have an apparently normal karyotype despite comprehensive cytogenetic analysis. Based on conventional cytogenetic analysis of banded chromosomes, we selected a series of 23 paediatric patients with acute myeloid leukaemia and performed whole genome array comparative genome hybridization (aCGH) using DNA samples derived from the same patients. Imbalances involving large chromosomal regions or entire chromosomes were detected by aCGH in seven of the patients studied. Results were validated by fluorescence in situ hybridization (FISH) to both interphase nuclei and metaphase chromosomes using appropriate bacterial artificial chromosome (BAC) probes. The majority of these copy number alterations (CNAs) were confirmed by FISH and found to localize to the interphase rather than metaphase nuclei. Furthermore, the proliferative states of the cells analyzed by FISH were tested by immunofluorescence using an antibody against the proliferation marker pKi67. Interestingly, these experiments showed that, in the vast majority of cases, the changes appeared to be confined to interphase nuclei in a non-proliferative status.This work was supported by a grant from Leukaemia Research UK (grant no. 0253). SJLK and RR were supported by the NIHR Biomedical Research
Centre, Oxford, with funding from the Department of Health’s NIHR Biomedical Research Centres funding schemeThis article is available through the Brunel Open Access Publishing Fund
Innate Structure of DNA Foci Restricts the Mixing of DNA from Different Chromosome Territories
The distribution of chromatin within the mammalian nucleus is constrained by its organization into chromosome territories (CTs). However, recent studies have suggested that promiscuous intra- and inter-chromosomal interactions play fundamental roles in regulating chromatin function and so might define the spatial integrity of CTs. In order to test the extent of DNA mixing between CTs, DNA foci of individual CTs were labeled in living cells following incorporation of Alexa-488 and Cy-3 conjugated replication precursor analogues during consecutive cell cycles. Uniquely labeled chromatin domains, resolved following random mitotic segregation, were visualized as discrete structures with defined borders. At the level of resolution analysed, evidence for mixing of chromatin from adjacent domains was only apparent within the surface volumes where neighboring CTs touched. However, while less than 1% of the nuclear volume represented domains of inter-chromosomal mixing, the dynamic plasticity of DNA foci within individual CTs allows continual transformation of CT structure so that different domains of chromatin mixing evolve over time. Notably, chromatin mixing at the boundaries of adjacent CTs had little impact on the innate structural properties of DNA foci. However, when TSA was used to alter the extent of histone acetylation changes in chromatin correlated with increased chromatin mixing. We propose that DNA foci maintain a structural integrity that restricts widespread mixing of DNA and discuss how the potential to dynamically remodel genome organization might alter during cell differentiation
Health Communication as a Public Health Training and Workforce Development Issue
Effective communication is one of the core competencies for public health professionals and is required for local health department (LHD) accreditation. Public health communication specialists play a critical role as conduits of health information, particularly with regard to managing relationships with media and the message that is ultimately represented by news outlets. However, capacity for engagement with traditional media in community health improvement at the local level has not been well-described. As part of a larger study examining the use and impact of the County Health Rankings in North Carolina, LHD media staffing and interaction with traditional media were examined through a cross-sectional, online survey, administered to North Carolina LHDs. Results indicate that most LHDs in North Carolina have staff designated to work with media, but few have dedicated staff or staff with an educational background in mass communication. Most communication staff enter their position with less than one year of experience, though almost all receive some training once on the job. Press releases are issued relatively infrequently, which implies that media engagement and message management are underdeveloped at the local level. These results suggest that health communication specialists are underutilized in LHDs and these skills should be emphasized in LHD hiring practices and in public health workforce development
3D genome organization
Copyright © The Author(s) 2022. Our genomes are highly organized spatially in three-dimensions (3D). In interphase nuclei, the genome is anchored and regulated by various nuclear scaffolds and structures, including the nuclear lamina at the nuclear edge, and nucleoli located more internally within the nucleoplasm. Recently, great effort has been made to understand the intricacies of 3D genome organization and its relevance to genomic and nuclear function. Over the years, many concepts, mathematical models, visual and biochemical methods, and analysis pipelines have been presented to study various aspects of this organization in a multidisciplinary manner, such as is also reflected within this collection
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