4,865 research outputs found
Architecture for Cognitive Networking within NASAs Future Space Communications Infrastructure
Future space mission concepts and designs pose many networking challenges for command, telemetry, and science data applications with diverse end-to-end data delivery needs. For future end-to-end architecture designs, a key challenge is meeting expected application quality of service requirements for multiple simultaneous mission data flows with options to use diverse onboard local data buses, commercial ground networks, and multiple satellite relay constellations in LEO, MEO, GEO, or even deep space relay links. Effectively utilizing a complex network topology requires orchestration and direction that spans the many discrete, individually addressable computer systems, which cause them to act in concert to achieve the overall network goals. The system must be intelligent enough to not only function under nominal conditions, but also adapt to unexpected situations, and reorganize or adapt to perform roles not originally intended for the system or explicitly programmed. This paper describes architecture features of cognitive networking within the future NASA space communications infrastructure, and interacting with the legacy systems and infrastructure in the meantime. The paper begins by discussing the need for increased automation, including inter-system collaboration. This discussion motivates the features of an architecture including cognitive networking for future missions and relays, interoperating with both existing endpoint-based networking models and emerging information-centric models. From this basis, we discuss progress on a proof-of-concept implementation of this architecture as a cognitive networking on-orbit application on the SCaN Testbed attached to the International Space Station
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Using Participatory Mapping to Diagnose Upstream Determinants of Health and Prescribe Downstream Policy-Based Interventions
Participatory mapping is a powerful methodology for working with community residents to examine social and environmental determinants of public health disparities. However, this empowering methodology has only been applied sparingly in public health research and practice, with limited examples in the literature. To address this literature gap, we 1) review participatory mapping approaches that may be applied to exploring place-based factors that affect community health, and 2) present a mixed-methods participatory geographic information systems (PGIS) examination of neighborhood assets (eg, streetlights) and challenges (eg, spaces of crime and violence) related to access to public parks in South Los Angeles, California. By taking a participatory, fine-grained spatial approach to examining public park access with input from 40 South Los Angeles adolescent and adult residents, our community-engaged PGIS approach identified tobacco shops as previously unrecognized community institutions that are associated with increased neighborhood crime and violence. Our investigation revealed unique challenges in community-level public park access that would likely have been overlooked by conventional spatial epidemiology and social science methods, such as surveys and questionnaires. Furthermore, our granular community-informed approach supported resident and stakeholder advocacy efforts toward reducing the proliferation of tobacco shops through community organizing and policy change initiatives. We thus contend that it would benefit public health research and practice to further integrate empowering, grassroots-based participatory mapping approaches toward informing advocacy efforts and policies that promote health and well-being in disadvantaged communities
Viral meningitis epidemics and a single, recent, recombinant and anthroponotic origin of swine vesicular disease virus
Background and objectives: Swine vesicular disease virus (SVDV) is a close relative of the human Enterovirus B serotype, coxsackievirus B5. As the etiological agent of a significant emergent veterinary disease, several studies have attempted to explain its origin. However, several key questions remain, including the full biological ancestry of the virus, and its geographical and temporal origin. Methodology: We sequenced near-complete genomes of 27 SVDV and 13 coxsackievirus B5 samples, all originally isolated between 1966 and 2006, and analysed these in conjunction with existing sequences and historical information. Results: While analyses incorporating 24 additional near-complete SVDV genomic sequences indicate clear signs of within-SVDV recombination, all 51 SVDV isolates remain monophyletic. This supports a hypothesis of a single anthroponotic transfer origin. Analysis of individual coding and non-coding regions supports that SVDV has a recombinant origin between coxsackievirus B5 and another Enterovirus B serotype, most likely coxsackievirus A9. Extensive Bayesian sequence-based analysis of the time of the most recent common ancestor of all analysed sequences places this within a few years around 1961. Epidemiological evidence points to China as an origin, but there are no available samples to test this conclusively. Conclusions and implications: Historical investigation and the clinical aspects of the involved Enterovirus B serotypes, makes the current results consistent with a hypothesis stating that SVDV originated through co-infection, recombination, and a single anthroponotic event, during large viral meningitis epidemics around 1960/1961 involving the ancestral serotypes. The exact geographical origin of SVDV may remain untestable due to historical aspects
Stat5 determines the development of mammary alveolar cells
Functional development of mammary epithelium during pregnancy depends on prolactin signaling. However, the underlying molecular and cellular events are not fully understood. We examined the specific contributions of the prolactin receptor (PrlR) and the signal transducers and activators of transcription 5a and 5b (referred to as Stat5) in the formation and differentiation of mammary alveolar epithelium. PrlR- and Stat5-null mammary epithelia were transplanted into wild-type hosts, and pregnancy-mediated development was investigated at a histological and molecular level. Stat5-null mammary epithelium developed ducts but failed to form alveoli, and no milk protein gene expression was observed. In contrast, PrlR-null epithelium formed alveoli-like structures with small open lumina. Electron microscopy revealed undifferentiated features of organelles and a perturbation of cell–cell contacts in PrlR- and Stat5-null epithelia. Expression of NKCC1, an Na-K-Cl cotransporter characteristic for ductal epithelia, and ZO-1, a protein associated with tight junction, were maintained in the alveoli-like structures of PrlR- and Stat5-null epithelia. In contrast, the Na-Pi cotransporter Npt2b, and the gap junction component connexin 32, usually expressed in secretory epithelia, were undetectable in PrlR- and Stat5- null mice. These data demonstrate that signaling via the PrlR and Stat5 is critical for the proliferation and differentiation of mammary alveoli during pregnancy
Informed consent, parental awareness, and reasons for participating in a randomised controlled study
BACKGROUND: The informed consent procedure plays a central role in
randomised controlled trials but has only been explored in a few studies
on children. AIM: To assess the quality of the informed consent process in
a paediatric setting. METHODS: A questionnaire was sent to parents who
volunteered their child (230 children) for a randomised, double blind,
placebo controlled trial of ibuprofen syrup to prevent recurrent febrile
seizures. RESULTS: 181 (79%) parents responded. On average, 73% of parents
were aware of the major study characteristics. A few had difficulty
understanding the information provided. Major factors in parents granting
approval were the contribution to clinical science (51%) and benefit to
the child (32%). Sociodemographic status did not influence initial
participation but west European origin of the father was associated with
willingness to participate in future trials. 89% of participants felt
positive about the informed consent procedure; however, 25% stated that
they felt obliged to participate. Although their reasons for granting
approval and their evaluation of the informed consent procedure did not
differ, relatively more were hesitant about participating in future.
Parents appreciated the investigator being on call 24 hours a day (38%)
and the extra medical care and information provided (37%) as advantages of
participation. Disadvantages were mainly the time consuming aspects and
the work involved (23%). CONCLUSIONS: Parents' understanding of trial
characteristics might be improved by designing less difficult informed
consent forms and by the investigator giving extra attention and
information to non-west European parents. Adequate measures should be
taken to avoid parents feeling obliged to participate, rather than giving
true informed consent
Signal transducer and activator of transcription (Stat) 5 controls the proliferation and differentiation of mammary alveolar epithelium
Functional development of mammary epithelium during pregnancy depends on prolactin signaling. However, the underlying molecular and cellular events are not fully understood. We examined the specific contributions of the prolactin receptor (PrlR) and the signal transducers and activators of transcription 5a and 5b (referred to as Stat5) in the formation and differentiation of mammary alveolar epithelium. PrlR- and Stat5-null mammary epithelia were transplanted into wild-type hosts, and pregnancy-mediated development was investigated at a histological and molecular level. Stat5-null mammary epithelium developed ducts but failed to form alveoli, and no milk protein gene expression was observed. In contrast, PrlR-null epithelium formed alveoli-like structures with small open lumina. Electron microscopy revealed undifferentiated features of organelles and a perturbation of cell–cell contacts in PrlR- and Stat5-null epithelia. Expression of NKCC1, an Na-K-Cl cotransporter characteristic for ductal epithelia, and ZO-1, a protein associated with tight junction, were maintained in the alveoli-like structures of PrlR- and Stat5-null epithelia. In contrast, the Na-Pi cotransporter Npt2b, and the gap junction component connexin 32, usually expressed in secretory epithelia, were undetectable in PrlR- and Stat5-null mice. These data demonstrate that signaling via the PrlR and Stat5 is critical for the proliferation and differentiation of mammary alveoli during pregnancy
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