398 research outputs found
Direct comparison of B-Type Natriuretic Peptide (BNP) and amino-terminal proBNP in a large population of patients with chronic and symptomatic heart failure: the Valsartan Heart Failure (Val-HeFT) data
Background: The B-type or brain natriuretic peptides
(BNP) and the amino-terminal probrain natriuretic peptide
(NT-proBNP) are good markers of prognosis and
diagnosis in chronic heart failure (HF). It is unclear,
however, whether differences in their biological characteristics
modify their clinical correlates and prognostic
performance in HF. This work aimed to provide a direct
comparison of the prognostic value of BNP and NTproBNP
in patients with chronic and stable HF.
Methods: We measured BNP and NT-proBNP at baseline
in 3916 patients enrolled in the Valsartan Heart
Failure Trial. To identify the variables associated with
both peptides, we conducted simple and multivariable
linear regression analyses. We used Cox multivariable
regression models to evaluate the independent prognostic
value for all-cause mortality, mortality and morbidity,
and hospitalization for HF. Prognostic performance
was assessed by pairwise comparisons of the area under
the curve of receiver-operator characteristic curves.
Results: NT-proBNP and BNP had similar relationships
with age, left ventrical ejection fraction, and internal
diameter and creatinine clearance. Either peptide
ranked as the first independent predictor of outcome
after adjustment for major confounding clinical characteristics.
ROC curves were almost superimposable for
all-cause mortality (area under the curve (SE): BNP
0.665 (0.011) vs NT-proBNP 0.679 (0.011); P 0.0734), but
NT-proBNP was superior to BNP for predicting mortality
and morbidity (P 0.032) or hospitalization for HF
(P 0.0143). Overall sensitivity and specificity ranged
from 0.590 to 0.696.
Conclusions: The natriuretic peptides BNP and NTproBNP
showed subtle differences in their relation to
clinical characteristics and prognostic performance in a
large population of patients with chronic and stable HF.
They were the most powerful independent markers of
outcome in HF
On the Filter Narrowing Issues in Elastic Optical Networks
This paper describes the problematic filter narrowing effect in the context of next-generation elastic optical networks. First, three possible scenarios are introduced: the transition from an actual fixed-grid to a flexigrid network, the generic full flexi-grid network, and a proposal for a filterless optical network. Next, we investigate different transmission techniques and evaluate the penalty introduced by the filtering effect when considering Nyquist wavelength division multiplexing, single side-band direct-detection orthogonal frequency division multiplexing, and symbol-rate variable dual polarization quadrature amplitude modulation. Also, different approaches to compensate for the filter narrowing effect are discussed. Results show that the specific needs per each scenario can be fulfilled by the aforementioned technologies and techniques or a combination of them, when balancing performance, network reach, and cost
Analysis of end-to-end multi-domain management and orchestration frameworks for software defined infrastructures: An architectural survey
Over the last couple of years, industry operators' associations issued requirements towards an end-to-end management and orchestration plane for 5G networks. Consequently, standard organisations started their activities in this domain. This article provides an analysis and an architectural survey of these initiatives and of the main requirements, proposes descriptions for the key concepts of domain, resource and service slicing, end-to-end orchestration and a reference architecture for the end-to-end orchestration plane. Then, a set of currently available or under development domain orchestration frameworks are mapped to this reference architecture. These frameworks, meant to provide coordination and automated management of cloud and networking resources, network functions and services, fulfil multi-domain (i.e. multi-technology and multi-operator) orchestration requirements, thus enabling the realisation of an end-to-end orchestration plane. Finally, based on the analysis of existing single-domain and multi-domain orchestration components and requirements, this paper presents a functional architecture for the end-to-end management and orchestration plane, paving the way to its full realisation
First Demonstration of MANTRA IPoWDM Convergent SDN Architecture using SONiC White Box and 400ZR/ZR+ Pluggables
In this work, the MANTRA (Metaverse ready Architectures for Open Transport) "Single"IP over Wavelength Division Multiplexing (IPoWDM) architecture is implemented and experimentally demonstrated in a network testbed employing three SDN Controllers (IP, Optical and Hierarchical) and Software for Open Networking in the Cloud (SONiC) white box equipped with 400ZR and 400ZR+ coherent pluggable transceivers
Augmented In-Band Telemetry to the User Equipment for beyond 5G Converged Packet-Optical Networks
Traffic monitoring through in-band telemetry is extended up to the User Equipment (UE), providing accurate e2e latency measurement. The UE becomes aware of its experienced service performance, enabling autonomous operations for faster automatic source-based Edge-Cloud steering
Coordinating Pluggable Transceiver Control in SONiC-based Disaggregated Packet-Optical Networks
Effective control of pluggable transceivers in SONiC-based packet-optical nodes is demonstrated. A workflow for multi-layer recovery upon soft failure detection is validated, showing no traffic disruption and fast node-driven coordination between packet and optical operations
First demonstration of multi-vendor and multi-domain EON with S-BVT and control interoperability over Pan-European testbed
The operation of multi-domain and multi-vendor EONs can be achieved by interoperable Sliceable Bandwidth Variable Transponders, a GMPLS / BGP-LS-based control plane and a planning tool. This paper reports the first full demonstration and validation this end-to-end architecture
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