Model of thermo-optic nonlinear dynamics of photonic crystal cavities

The wavelength scale confinement of light offered by photonic crystal (PhC) cavities is one of the fundamental features on which many important on-chip photonic components are based, opening silicon photonics to a wide range of applications from telecommunications to sensing. This trapping of light in a small space also greatly enhances optical nonlinearities and many potential applications build on these enhanced light-matter interactions. In order to use PhCs effectively for this purpose it is necessary to fully understand the nonlinear dynamics underlying PhC resonators. In this work, we derive a first principles thermal model outlining the nonlinear dynamics of optically pumped silicon two-dimensional (2D) PhC cavities by calculating the temperature distribution in the system in both time and space. We demonstrate that our model matches experimental results well and use it to describe the behavior of different types of PhC cavity designs. Thus, we demonstrate the model's capability to predict thermal nonlinearities of arbitrary 2D PhC microcavities in any material, only by substituting the appropriate physical constants. This renders the model critical for the development of nonlinear optical devices prior to fabrication and characterization

Integrated HTA and FMECA methodology for the evaluation of robotic surgery

Robotic surgery has been strongly improved since the beginning of the twenty-first century and chased important level of technical and clinical performances. Within the robotic area, the most worldwide used surgical robot is the da Vinci® system made by Intuitive Surgical Inc. The aim of this study was to evaluate at the hospital scale the robotic surgery (Hospital –Based Health Technology Assessment) in comparison to the open and laparoscopic procedures yet combining a FMECA analysis to accurately assess all those aspects involving patient and staff safety. The total number of robotic procedures directly observed by the surgical department and reported in the following study was 44, including 28 urology interventions and 16 general surgeries. The study confirmed clinical benefits carried out with the robot but bigger complexity in managing the whole surgical system in terms of structural needs, staff and technology. For the future, further steps regard the necessity to dispose of a wider number of robotic procedures in order to strength the analysis reliability and complete the socio-economic assessment with medium and long terms observation. Finally a new FMECA application will be essential to monitor the real effects of the suggested actions on the evaluated risks according to the already known and new failure modes

Methods to account for movement and flexibility in cryo-EM data processing

Recent advances in direct electron detectors and improved CMOS cameras have been accompanied by the development of a range of software to take advantage of the data they produce. In particular they allow for the correction of two types of motion in cryo electron microscopy samples: motion correction for movements of the sample particles in the ice, and differential masking to account for heterogeneity caused by flexibility within protein complexes. Here we provide several scripts that allow users to move between RELION and standalone motion correction and centring programs. We then compare the computational cost and improvements in data quality with each program. We also describe our masking procedures to account for conformational flexibility. For the different elements of this study we have used three samples; a high symmetry virus, flexible protein complex (~1 MDa) and a relatively small protein complex (~550 kDa), to benchmark four widely available motion correction packages. Using these as test cases we demonstrate how motion correction and differential masking, as well as an additional particle re-centring protocol can improve final reconstructions when used within the RELION image-processing package

Programmable Edge-to-Cloud Virtualization for 5G Media Industry: The 5G-MEDIA Approach

To ensure high Quality of Experience (QoE) for end users, many media applications require significant quantities of computing and network resources, making their realization challenging in resource constrained environments. In this paper, we present the approach of the 5G-MEDIA project, providing an integrated programmable service platform for the development, design and operations of media applications in 5G networks, facilitating media service management across the service life cycle. The platform offers tools to service developers for efficient development, testing and continuous correction of services. One step further, it provides a service virtualization platform offering horizontal services, such as a Media Service Catalogue and accounting services, as well as optimization mechanisms to flexibly adapt service operations to dynamic conditions with efficient use of infrastructure resources. The paper outlines three use cases where the platform was tested and validated

Polarization Control in Integrated Graphene-Silicon Quantum Photonics Waveguides

We numerically investigated the use of graphene nanoribbons placed on top of silicon-on-insulator (SOI) strip waveguides for light polarization control in silicon photonic-integrated waveguides. We found that two factors mainly affected the polarization control: the graphene chemical potential and the geometrical parameters of the waveguide, such as the waveguide and nanoribbon widths and distance. We show that the graphene chemical potential influences both TE and TM polarizations almost in the same way, while the waveguide width tapering enables both TE-pass and TM-pass polarizing functionalities. Overall, by increasing the oxide spacer thickness between the silicon waveguide and the top graphene layer, the device insertion losses can be reduced, while preserving a high polarization extinction ratio

Comparing the safety and effectiveness of five leading new-generation devices for transcatheter aortic valve implantation: Twelve-month results from the RISPEVA study

Objectives. The management of severe aortic stenosis has been revolutionized by the introduction of transcatheter aortic valve implantation (TAVI), especially in patients at intermediate, high, or prohibitive surgical risk. There is uncertainty, however, regarding the comparative effectiveness and safety of contemporary TAVI devices. Methods. We queried detailed data from the ongoing national Italian TAVI registry and compared baseline features, procedural details, and 12-month outcomes of Acurate Neo (Boston Scientific), Evolut Pro/R (Medtronic), Lotus (Boston Scientific), Portico (Abbott Vascular), and Sapien/ Sapien S3 Ultra (Edward Lifesciences) transcatheter aortic valves. Several endpoints were collected and appraised, including the composite of death, stroke, myocardial infarction (MI), major bleeding, major vascular complication, surgical aortic valve replacement and transcatheter aortic valve reimplantation, which were deemed major adverse events (MAEs). Results. A total of 1976 patients were included, with 234 treated with Acurate, 703 with Evolut, 151 with Lotus, 347 with Portico, and 541 with Sapien. Twelve-month events were not significantly different among the 5 devices, including death (P=.29) and MAE (P=.21), with the notable exception of major vascular complications, which were more common with Acurate and Sapien (P<.001) and permanent pacemaker implantation, which was more frequent with Lotus and Evolut (P<.001). Differences in MAE were more pronounced in women and subjects with prior cardiac surgery, with the lowest event rates in the Evolut group. Propensity-score adjusted analysis suggested that Acurate, Evolut, Portico, and Sapien were all associated with similarly favorable results, whereas adverse events were more evident with Lotus (P<.05). Conclusion. Leading current-generation TAVI devices offer similarly favorable results at mid-term follow-up

Input Clinical Parameters for Cardiac Heart Failure Characterization Using Machine Learning

Congestive Heart Failure (CHF) is a serious chronic cardiac condition that brings high risk of urgent hospi- talization and could lead to death. In this work we show how all the input clinical parameters for classifying CHF using Machine Learning can be acquired. The requested input are Blood Pres- sure, Heart Rate, Brain Natriuretic Peptide, Electrocardio- gram, Blood Oxygen Saturation, Height, Weight and Ejection Fraction. The next step will be designing a novel device and con- necting it to our Machine Learning classifier. A particular at- tention will be put to the assessment of electromagnetic compat- ibility (EMC) with other devices, taking into account that this new device will be used in many different settings (home, out- door, etc.

Towards Serverless NFV for 5G Media Applications

The advent of virtualization and IaaS have revolutionized the telecom industry via SDN/NFV. A new wave of cloud-native PaaS promises to further improve SDN/NFV performance, portability, and cost-efficiency. In this poster, we highlight a work in progress being done in the 5G-MEDIA project [2], which pioneers the application of the serverless paradigm to NFV in the context of media intensive applications in 5G networks. Motivational use cases include tele-immersive gaming, mobile journalism and UHD content distribution. For example, consider a next-gen e-sport, in which bouts between gamers last only a few minutes. FaaS offers a clear cost-efficiency benefit for hosting such applications. An architecture is shown in Fig. 1. It includes i) an Application/Service Development Kit (SDK) to enable access to media applications development tools; ii) a Service Virtualization Platform (SVP) to run the ETSI MANO framework, the Media Service MAPE optimization component and the VIM and WIM plugins to enable NFVIs integration; iii) different NFVIs to execute media-specific VNFs. FaaS VIM is implemented for integration of FaaS with the rest of the MANO stack. It allows mixing FaaS and "regular" VNFs within the same media forwarding graph. For reference implementation, Apache OpenWhisk [1] and Kubernetes are used. The main challenge is extending the programming model to support groups of actions communicating over a network, while retaining the simplicity of FaaS