529 research outputs found

    ProFaaStinate: Delaying Serverless Function Calls to Optimize Platform Performance

    Full text link
    Function-as-a-Service (FaaS) enables developers to run serverless applications without managing operational tasks. In current FaaS platforms, both synchronous and asynchronous calls are executed immediately. In this paper, we present ProFaaStinate, which extends serverless platforms to enable delayed execution of asynchronous function calls. This allows platforms to execute calls at convenient times with higher resource availability or lower load. ProFaaStinate is able to optimize performance without requiring deep integration into the rest of the platform, or a complex systems model. In our evaluation, our prototype built on top of Nuclio can reduce request response latency and workflow duration while also preventing the system from being overloaded during load peaks. Using a document preparation use case, we show a 54% reduction in average request response latency. This reduction in resource usage benefits both platforms and users as cost savings.Comment: Accepted for publication in Proc. of 9th International Workshop on Serverless Computing (WoSC 23

    Lotus: Serverless In-Transit Data Processing for Edge-based Pub/Sub

    Full text link
    Publish-subscribe systems are a popular approach for edge-based IoT use cases: Heterogeneous, constrained edge devices can be integrated easily, with message routing logic offloaded to edge message brokers. Message processing, however, is still done on constrained edge devices. Complex content-based filtering, the transformation between data representations, or message extraction place a considerable load on these systems, and resulting superfluous message transfers strain the network. In this paper, we propose Lotus, adding in-transit data processing to an edge publish-subscribe middleware in order to offload basic message processing from edge devices to brokers. Specifically, we leverage the Function-as-a-Service paradigm, which offers support for efficient multi-tenancy, scale-to-zero, and real-time processing. With a proof-of-concept prototype of Lotus, we validate its feasibility and demonstrate how it can be used to offload sensor data transformation to the publish-subscribe messaging middleware

    To The Sun / words by David W. Guion

    Get PDF
    Cover: part of a series titled Five Imaginary Early Louisiana Songs of Slavery; Publisher: G. Schirmer Inc. (New York)https://egrove.olemiss.edu/sharris_d/1104/thumbnail.jp

    Global myocardial longitudinal strain in a general population—associations with blood pressure and subclinical heart failure: The Tromsø Study

    Get PDF
    This is a post-peer-review, pre-copyedit version of an article published in International Journal of Cardiovascular Imaging. The final authenticated version is available online at: https://doi.org/10.1007/s10554-019-01741-3.The early detection of subclinical myocardial dysfunction can contribute to the treatment and prevention of heart failure (HF). The aim of the study was to (i) describe myocardial global longitudinal strain (GLS) patterns in a large general population sample from Norway and their relation to established cardiovascular disease (CVD) risk factors; (ii) to determine its normal thresholds in healthy individuals and (iii) ascertain the relation of myocardial GLS to stage A subclinical heart failure (SAHF). Participants (n = 1855) of the 7th survey of the population-based Tromsø Study of Norway (2015–2016) with GLS measurements were studied. Linear and logistic regression models were used for assessment of the associations between CVD risk factors and GLS. Mean GLS (SD) in healthy participants was − 15.9 (2.7) % in men and − 17.8 (3.1) % in women. Among healthy subjects, defined as those without known cardiovascular diseases and comorbidities, GLS declined with age. An increase of systolic blood pressure (SBP) of 10 mm Hg was associated with a 0.2% GLS reduction. Myocardial GLS in individuals with SAHF was 1.2% lower than in participants without SAHF (p < 0.001). Mean myocardial GLS declines with age in both sexes, both in a general population and in the healthy subsample. SBP increase associated with GLS decline in women. Our findings indicate high sensitivity of GLS for early subclinical stages of HF

    Managing Data Replication and Distribution in the Fog with FReD

    Full text link
    The heterogeneous, geographically distributed infrastructure of fog computing poses challenges in data replication, data distribution, and data mobility for fog applications. Fog computing is still missing the necessary abstractions to manage application data, and fog application developers need to re-implement data management for every new piece of software. Proposed solutions are limited to certain application domains, such as the IoT, are not flexible in regard to network topology, or do not provide the means for applications to control the movement of their data. In this paper, we present FReD, a data replication middleware for the fog. FReD serves as a building block for configurable fog data distribution and enables low-latency, high-bandwidth, and privacy-sensitive applications. FReD is a common data access interface across heterogeneous infrastructure and network topologies, provides transparent and controllable data distribution, and can be integrated with applications from different domains. To evaluate our approach, we present a prototype implementation of FReD and show the benefits of developing with FReD using three case studies of fog computing applications

    Self-reported health as a predictor of mortality: A cohort study of its relation to other health measurements and observation time.

    Get PDF
    Self-reported health (SRH) is widely used as an epidemiological instrument given the changes in public health since its introduction in the 1980s. We examined the association between SRH and mortality and how this is affected by time and health measurements in a prospective cohort study using repeated measurements and physical examinations of 11652 men and 12684 women in Tromsø, Norway. We used Cox proportional hazard regression to estimate hazard ratios (HRs) of death for SRH, controlling for pathology, biometrics, smoking, sex and age. SRH predicted mortality independently of other, more objective health measures. Higher SRH was strongly associated with lower mortality risk. Poor SRH had HR 2.51 (CI: 2.19, 2.88). SRH is affected by disease, mental health and other risk factors, but these factors had little impact on HRs (Poor SRH: HR 1.99; CI: 1.72, 2.31). SRH predicted mortality, but with a time-dependent effect. Time strongly affected the hazard ratio for mortality, especially after ten-year follow-up (Poor SRH HR 3.63 at 0-5 years decreased to HR 1.58 at 15-21 years). SRH has both methodological and clinical value. It should not be uncritically utilised as a replacement instrument when measures of physical illness and other objective health measures are lacking

    Management of patients with acute ST-segment elevation myocardial infarction in Russian hospitals adheres to international guidelines

    Get PDF
    Objective - Russia has one of the highest cardiovascular mortality rates. Modernisation of the Russian health system has been accompanied by a substantial increase in uptake of percutaneous coronary intervention (PCI), which substantially reduces the risk of mortality in patients with acute ST-elevation myocardial infarction (STEMI). This paper aims to describe contemporary Hospital treatment of acute STEMI among patients in a range of hospitals in the Russian Federation. Methods - This study used data from a prospective observational cohort of 1128 suspected patients with myocardial infarction recruited in both PCI and non-PCI hospitals across 13 regions and multiple levels of the health system in Russia. The primary objective was to examine the use of reperfusion strategies in patients with STEMI. Results - Among patients reaching PCI centres within 12 hours of symptom onset, the vast majority received angiography and PCI, regardless of age, sex and comorbidity, in line with current European Society of Cardiology guidelines. Conclusion- Patients reaching Russian hospitals are very likely to receive appropriate treatment, although performance varies. The best hospitals can serve as beacons of good practice as PCI facilities continue to expand across Russia where geography allows

    The BID Domain of Type IV Secretion Substrates Forms a Conserved Four-Helix Bundle Topped with a Hook

    Get PDF
    The BID (Bep intracellular delivery) domain functions as secretion signal in a subfamily of protein substrates of bacterial type IV secretion (T4S) systems. It mediates transfer of (1) relaxases and the attached DNA during bacterial conjugation, and (2) numerous Bartonella effector proteins (Beps) during protein transfer into host cells infected by pathogenic Bartonella species. Furthermore, BID domains of Beps have often evolved secondary effector functions within host cells. Here, we provide crystal structures for three representative BID domains and describe a novel conserved fold characterized by a compact, antiparallel four-helix bundle topped with a hook. The conserved hydrophobic core provides a rigid scaffold to a surface that, despite a few conserved exposed residues and similarities in charge distribution, displays significant variability. We propose that the genuine function of BID domains as T4S signal may primarily depend on their rigid structure, while the plasticity of their surface may facilitate adaptation to secondary effector functions

    Adverse Outcome Pathways during Early Fish Development: A Conceptual Framework for Identification of Chemical Screening and Prioritization Strategies

    Get PDF
    The fish early life-stage (FELS) test guideline (OECD 210 or OCSPP 850.1400) is the most frequently used bioassay for predicting chronic fish toxicity and supporting aquatic ecological risk assessments around the world. For each chemical, the FELS test requires a minimum of 360 fish and 1 to 3 months from test initiation to termination. Although valuable for predicting fish full life-cycle toxicity, FELS tests are labor and resource intensive and, due to an emphasis on apical endpoints, provide little to no information about chemical mode of action. Therefore, the development and implementation of alternative testing strategies for screening and prioritizing chemicals has the potential to reduce the cost and number of animals required for estimating FELS toxicity and, at the same time, provides insights into mechanisms of toxicity. Using three reference chemicals with well-established yet distinct adverse outcome pathways (AOPs) in early life stages of fish, we proposed FELS-specific AOPs as conceptual frameworks for identifying useful chemical screening and prioritization strategies. The reference chemicals selected as case studies were a cardiotoxic aryl hydrocarbon receptor agonist (2,3,7,8-tetrachlorodibenzo-p-dioxin), neurotoxic acetylcholinesterase inhibitor (chlorpyrifos), and narcotic surfactant (linear alkylbenzene sulfonate). Using qualitative descriptions for each chemical during early fish development, we developed generalized AOPs and, based on these examples, proposed a three-tiered testing strategy for screening and prioritizing chemicals for FELS testing. Linked with biologically based concentration-response models, a tiered testing strategy may help reduce the reliance on long-term and costly FELS tests required for assessing the hazard of thousands of chemicals currently in commerc

    Online-Panel: Communities und Netzwerke als Treiber des digitalen Wandels: Erfahrungen, Perspektiven und Ausblick

    Get PDF
    Enterprise Social Networks und Corporate Communities sind zentrale Elemente von Unternehmensinitiativen im Bereich der Digitalen Transformation (Brück, 2018; Schirmer, 2016; Wagner et al., 2016). Sie fungieren als virtuelle Begegnungsräume und helfen dabei, Mitarbeiter und deren Wissen über Abteilungsbzw. Organisationsgrenzen hinweg besser zu vernetzen sowie die Qualität und Geschwindigkeit der Zusammenarbeit zu verbessern (Clauss et al., 2019). Das geschieht zum Beispiel, indem sich Mitarbeiter in Communities zusammenfinden und gemeinsam an neuen Ideen oder Produkten arbeiten. Auch kann schneller und gezielter auf Expertenwissen zugegriffen werden (Wagner & Schirmer, 2016; Wagner et al., 2017). Damit stellen Enterprise Social Networks und Corporate Communities wichtige Instrumente moderner Wissensarbeit (Wagner et al., 2014) und Katalysatoren des strategischen Wandels dar (Wagner & Schirmer, 2016; Wagner & Brück 2020)
    • …
    corecore