18 research outputs found
Global state, local decisions: Decentralized NFV for ISPs via enhanced SDN
The network functions virtualization paradigm is rapidly gaining interest among Internet service providers. However, the transition to this paradigm on ISP networks comes with a unique set of challenges: legacy equipment already in place, heterogeneous traffic from multiple clients, and very large scalability requirements. In this article we thoroughly analyze such challenges and discuss NFV design guidelines that address them efficiently. Particularly, we show that a decentralization of NFV control while maintaining global state improves scalability, offers better per-flow decisions and simplifies the implementation of virtual network functions. Building on top of such principles, we propose a partially decentralized NFV architecture enabled via an enhanced software-defined networking infrastructure. We also perform a qualitative analysis of the architecture to identify advantages and challenges. Finally, we determine the bottleneck component, based on the qualitative analysis, which we implement and benchmark in order to assess the feasibility of the architecture.Peer ReviewedPostprint (author's final draft
Intravascular papillary endothelial hyperplasia: An unusual histopathological entity
Intravascular papillary endothelial hyperplasia (Masson′s tumor) is a benign lesion of the skin and subcutaneous tissue consisting of a reactive proliferation of endothelial cells with papillary formations related to a thrombus. It poses a diagnostic challenge as the clinical signs and symptoms are nonspecific and may mimic a soft tissue sarcoma. The diagnosis is based on histopathology. Here we report two cases of Masson′s hemangioma occurring on the upper lip and on the left hand
Two novel acyl sucroses from <i style="">Petunia nyctaginiflora</
648-650Two acyl sucroses, isolated
from Petunia nyctaginiflora Jussieu
(Solanaceae) have been characterized chemically as 2,3,4-tri(5-methylhexanoyl)--D-glucopyranosyl--D-6-acetyl fructoÂfuranoÂside
4 and 2,3,4-tri(6-methylheptanoyl)--D-glucopyranoÂsyl--D-6-acetyl
fructofuranoside 6, on the basis of
chemical and spectroscopic evidence
Endometrioid carcinoma infiltrating atypical leiomyoma: A mimicker of malignant mixed Mullerian tumor
Atypical or symplastic leiomyoma is a rare histological variant of leiomyoma. This is a case report of 63-year-old patient who underwent hysterectomy with bilateral salpingo-oophorectomy. Histopathology of the polypoid growth seen in the endometrial cavity revealed atypical leiomyoma infiltrated by endometrioid cancer. Atypical leiomyoma can be misdiagnosed as leiomyosarcoma. Thus, carcinosarcoma was ruled out as it has an ominous prognosis. A diagnosis of atypical leiomyoma infiltrated by endometrioid cancer was given. We report this case as there are very few case reports of the above two pathology occurring simultaneously in the same patient
Global state, local decisions: Decentralized NFV for ISPs via enhanced SDN
The network functions virtualization paradigm is rapidly gaining interest among Internet service providers. However, the transition to this paradigm on ISP networks comes with a unique set of challenges: legacy equipment already in place, heterogeneous traffic from multiple clients, and very large scalability requirements. In this article we thoroughly analyze such challenges and discuss NFV design guidelines that address them efficiently. Particularly, we show that a decentralization of NFV control while maintaining global state improves scalability, offers better per-flow decisions and simplifies the implementation of virtual network functions. Building on top of such principles, we propose a partially decentralized NFV architecture enabled via an enhanced software-defined networking infrastructure. We also perform a qualitative analysis of the architecture to identify advantages and challenges. Finally, we determine the bottleneck component, based on the qualitative analysis, which we implement and benchmark in order to assess the feasibility of the architecture.Peer Reviewe
Crosstalk with lung epithelial cells regulates Sfrp2-mediated latency in breast cancer dissemination
The process of metastasis is complex1. In breast cancer, there are frequently long time intervals between cells leaving the primary tumour and growth of overt metastases2,3. Reasons for disease indolence and subsequent transition back to aggressive growth include interactions with myeloid and fibroblastic cells in the tumour microenvironment and ongoing immune surveillance4-6. However, the signals that cause actively growing cells to enter an indolent state, thereby enabling them to survive for extended periods of time, are not well understood. Here we reveal how the behaviour of indolent breast cancer cells in the lung is determined by their interactions with alveolar epithelial cells, in particular alveolar type 1 cells. This promotes the formation of fibronectin fibrils by indolent cells that drive integrin-dependent pro-survival signals. Combined in vivo RNA sequencing and drop-out screening identified secreted frizzled-related protein 2 (SFRP2) as a key mediator of this interaction. Sfrp2 is induced in breast cancer cells by signals from lung epithelial cells and promotes fibronectin fibril formation and survival, whereas blockade of Sfrp2 expression reduces the burden of indolent disease