Dynamic Virtual Network Reconfiguration Over SDN Orchestrated Multitechnology Optical Transport Domains

Network virtualization is an emerging technique that enables multiple tenants to share an underlying physical infrastructure, isolating the traffic running over different virtual infrastructures/tenants. This technique aims to improve network utilization, while reducing the complexities in terms of network management for operators. Applied to this context, software defined networking (SDN) paradigm can ease network configurations by enabling network programmability and automation, which reduces the amount of operations required from both service and infrastructure providers. SDN techniques are decreasing vendor lock-in issues due to specific configuration methods or protocols. Application-based Network Operations (ABNO) is a toolbox of key network functional components with the goal of offering application-driven network management. Service provisioning using ABNO may involve direct configuration of data plane elements or delegate it to several control plane modules. We validate the applicability of ABNO to multi-tenant virtual networks in multi-technology optical domains based on two scenarios, in which multiple control plane instances are orchestrated by the architecture. Congestion Detection and Failure Recovery, are chosen to demonstrate fast recalculation and reconfiguration, while hiding the configurations in the physical layer from the upper layer.Grant numbers : supported by the Spanish Ministry of Economy and Competitiveness through the project FARO (TEC2012-38119)

Control orchestration protocol:unified transport API for distributed cloud and network orchestration

In the context of the fifth generation of mobile technology (5G), multiple technologies will converge into a unified end-to-end system. For this purpose, software defined networking (SDN) is proposed, as the control paradigm will integrate all network segments and heterogeneous optical and wireless network technologies together with massive storage and computing infrastructures. The control orchestration protocol is presented as a unified transport application programming interface solution for joint cloud/network orchestration, allowing interworking of heterogeneous control planes to provide provisioning and recovery of quality of service (QoS)-aware end-to-end services. End-to-end QoS is guaranteed by provisioning and restoration schemes, which are proposed for optical circuit/packet switching restoration by means of signal monitoring and adaptive modulation and adaptive route control, respectively. The proposed solution is experimentally demonstrated in an international multi-partner test bed, which consists of a multi-domain transport network comprising optical circuit switching and optical packet switching domains controlled by SDN/OpenFlow and Generalized Multiprotocol Label Switching (GMPLS) control planes and a distributed cloud infrastructure. The results show the dynamic provisioning of IT and network resources and recovery capabilities of the architecture.Grant numbers : This work was partially supported by the Spanish MINECO project DESTELLO (TEC2015-69256-R)

SDN-based Network Orchestration of Variable-capacity Optical Packet Switching Network over Programmable Flexi-grid Elastic Optical Path Network

A multidomain and multitechnology optical network orchestration is demonstrated in an international testbed located in Japan, the U.K., and Spain. The application-based network operations architecture is proposed as a carrier software-defined network solution for provisioning end-to-end optical transport services through a multidomain multitechnology network scenario, consisting of a 46–108 Gb/s variable-capacity OpenFlow-capable optical packet switching network and a programmable, flexi-grid elastic optical path network

The impacts of increased heat stress events on wheat yield under climate change in China

China is the largest wheat producing country in the world. Wheat is one of the two major staple cereals consumed in the country and about 60% of Chinese population eats the grain daily. To safeguard the production of this important crop, about 85% of wheat areas in the country are under irrigation or high rainfall conditions. However, wheat production in the future will be challenged by the increasing occurrence and magnitude of adverse and extreme weather events. In this paper, we present an analysis that combines outputs from a wide range of General Circulation Models (GCMs) with observational data to produce more detailed projections of local climate suitable for assessing the impact of increasing heat stress events on wheat yield. We run the assessment at 36 representative sites in China using the crop growth model CSM-CropSim Wheat of DSSAT 4.5. The simulations based on historical data show that this model is suitable for quantifying yield damages caused by heat stress. In comparison with the observations of baseline 1996-2005, our simulations for the future indicate that by 2100, the projected increases in heat stress would lead to an ensemble-mean yield reduction of –7.1% (with a probability of 80%) and –17.5% (with a probability of 96%) for winter wheat and spring wheat, respectively, under the irrigated condition. Although such losses can be fully compensated by CO2 fertilization effect as parameterized in DSSAT 4.5, a great caution is needed in interpreting this fertilization effect because existing crop dynamic models are unable to incorporate the effect of CO2 acclimation (the growth enhancing effect decreases over time) and other offsetting forces

Percutaneous Cryoablation of Pulmonary Metastases from Colorectal Cancer

Objective: To evaluate the safety and efficacy of cryoablation for metastatic lung tumors from colorectal cancer. Methods: The procedures were performed on 24 patients (36–82 years of age, with a median age of 62; 17 male patients, 7 female patients) for 55 metastatic tumors in the lung, during 30 sessions. The procedural safety, local progression free interval, and overall survival were assessed by follow-up computed tomographic scanning performed every 3–4 months. Results: The major complications were pneumothorax, 19 sessions (63%), pleural effusion, 21 sessions (70%), transient and self-limiting hemoptysis, 13 sessions (43%) and tract seeding, 1 session (3%). The 1- and 3-year local progression free intervals were 90.8 % and 59%, respectively. The 3-years local progression free intervals of tumors #15 mm in diameter was 79.8 % and that of tumors.15 mm was 28.6 % (p = 0.001; log-rank test). The 1- and 3-year overall survival rates were 91% and 59.6%, respectively. Conclusion: The results indicated that percutaneous cryoablation is a feasible treatment option. The local progression fre

Intra-Aortic Clusters Undergo Endothelial to Hematopoietic Phenotypic Transition during Early Embryogenesis

Intra-aortic clusters (IACs) attach to floor of large arteries and are considered to have recently acquired hematopoietic stem cell (HSC)-potential in vertebrate early mid-gestation embryos. The formation and function of IACs is poorly understood. To address this issue, IACs were characterized by immunohistochemistry and flow cytometry in mouse embryos. Immunohistochemical analysis revealed that IACs simultaneously express the surface antigens CD31, CD34 and c-Kit. As embryos developed from 9.5 to 10.5 dpc, IACs up-regulate the hematopoietic markers CD41 and CD45 while down-regulating the endothelial surface antigen VE-cadherin/CD144, suggesting that IACs lose endothelial phenotype after 9.5 dpc. Analysis of the hematopoietic potential of IACs revealed a significant change in macrophage CFC activity from 9.5 to 10.5 dpc. To further characterize IACs, we isolated IACs based on CD45 expression. Correspondingly, the expression of hematopoietic transcription factors in the CD45(neg) fraction of IACs was significantly up-regulated. These results suggest that the transition from endothelial to hematopoietic phenotype of IACs occurs after 9.5 dpc

Staging investigations for oesophageal cancer: a meta-analysis

The aim of the study was to compare the diagnostic performance of endoscopic ultrasonography (EUS), computed tomography (CT), and 18F-fluoro-2-deoxy-D-glucose positron emission tomography (FDG-PET) in staging of oesophageal cancer. PubMed was searched to identify English-language articles published before January 2006 and reporting on diagnostic performance of EUS, CT, and/or FDG-PET in oesophageal cancer patients. Articles were included if absolute numbers of true-positive, false-negative, false-positive, and true-negative test results were available or derivable for regional, celiac, and abdominal lymph node metastases and/or distant metastases. Sensitivities and specificities were pooled using a random effects model. Summary receiver operating characteristic analysis was performed to study potential effects of study and patient characteristics. Random effects pooled sensitivities of EUS, CT, and FDG-PET for regional lymph node metastases were 0.80 (95% confidence interval 0.75–0.84), 0.50 (0.41–0.60), and 0.57 (0.43–0.70), respectively, and specificities were 0.70 (0.65–0.75), 0.83 (0.77–0.89), and 0.85 (0.76–0.95), respectively. Diagnostic performance did not differ significantly across these tests. For detection of celiac lymph node metastases by EUS, sensitivity and specificity were 0.85 (0.72–0.99) and 0.96 (0.92–1.00), respectively. For abdominal lymph node metastases by CT, these values were 0.42 (0.29–0.54) and 0.93 (0.86–1.00), respectively. For distant metastases, sensitivity and specificity were 0.71 (0.62–0.79) and 0.93 (0.89–0.97) for FDG-PET and 0.52 (0.33–0.71) and 0.91 (0.86–0.96) for CT, respectively. Diagnostic performance of FDG-PET for distant metastases was significantly higher than that of CT, which was not significantly affected by study and patient characteristics. The results suggest that EUS, CT, and FDG-PET each play a distinctive role in the detection of metastases in oesophageal cancer patients. For the detection of regional lymph node metastases, EUS is most sensitive, whereas CT and FDG-PET are more specific tests. For the evaluation of distant metastases, FDG-PET has probably a higher sensitivity than CT. Its combined use could however be of clinical value, with FDG-PET detecting possible metastases and CT confirming or excluding their presence and precisely determining the location(s)