Mechanical thrombectomy in acute stroke – Five years of experience in Poland

Objectives Mechanical thrombectomy (MT) is not reimbursed by the Polish public health system. We present a description of 5 years of experience with MT in acute stroke in Comprehensive Stroke Centers (CSCs) in Poland. Methods and results We retrospectively analyzed the results of a structured questionnaire from 23 out of 25 identified CSCs and 22 data sets that include 61 clinical, radiological and outcome measures. Results Most of the CSCs (74%) were founded at University Hospitals and most (65.2%) work round the clock. In 78.3% of them, the working teams are composed of neurologists and neuro-radiologists. All CSCs perform CT and angio-CT before MT. In total 586 patients were subjected to MT and data from 531 of them were analyzed. Mean time laps from stroke onset to groin puncture was 250±99min. 90.3% of the studied patients had MT within 6h from stroke onset; 59.3% of them were treated with IV rt-PA prior to MT; 15.1% had IA rt-PA during MT and 4.7% – emergent stenting of a large vessel. M1 of MCA was occluded in 47.8% of cases. The Solitaire device was used in 53% of cases. Successful recanalization (TICI2b–TICI3) was achieved in 64.6% of cases and 53.4% of patients did not experience hemorrhagic transformation. Clinical improvement on discharge was noticed in 53.7% of cases, futile recanalization – in 30.7%, mRS of 0–2 – in 31.4% and mRS of 6 in 22% of cases. Conclusion Our results can help harmonize standards for MT in Poland according to international guidelines

ANALYSIS OF SELECTED CONTEMPORARY THREATS TO GAS INFRASTRUCTURE

Nowadays, companies are increasingly using a risk-based approach to achieving their business goals. A key element of this approach is the identification of threats that may materialize and affect the functioning of the company. Following the example of the gas sector, with the gas infrastructure as the subject of research, the authors presented selected contemporary gas network threats that may occur within the mentioned sector

Analysis of selected contemporary threats to gas infrastructure

Nowadays, companies are increasingly using a risk-based approach to achieve their business goals. A key element of this approach is the identification of threats that may materialize and affect the functioning of the company. Following the example of the gas sector, with the gas infrastructure as the subject of research, the authors presented selected contemporary gas network threats that may occur within the mentioned sector

Optimization of Content Caching in Content-Centric Network

Video on demand (VoD) systems currently use content delivery networks (CDN) to distribute content to users, whose performance and effectiveness depends on the architecture, the number and the geographical location of CDN nodes deployed by CDN providers or ISP(s) itself. Content-Centric Networking (CCN), with the benefits of caching and sharing content by every node in the network, suggests an alternative: a collaborative caching system exploiting the maximum capacity of infrastructure for the high performance of video delivery services. However, a CCN-based architecture to support efficient VoD delivery raises important questions about the optimal routing and caching strategies with constraints on the architecture and capacities of the system. We investigate models and algorithms for addressing these optimization problems. We study different solutions for the routing and caching optimization problems and compare the solutions produced with the optimal solution under various assumptions. We also contribute to an analysis of the caching investment under the competition among multiple interconnected ISPs. Our numerical results show the influence of throwing caching at the problem in different locations, on the system performance and its related cost

Energy Efficiency of Comminution and Extrusion of Maize Substrates Subjected to Methane Fermentation

The production of methane in the anaerobic digestion process is a proven technology, but it is characterized by low cost-effectiveness. The pretreatment of substrates seems to be a promising technology, which may increase the cost-effectiveness of biogas installations. The aim of the study was to investigate the influence of the comminution and extrusion of maize silage and maize straw silage on the course and yield of anaerobic digestion. The use of a pretreatment (comminution, extrusion) is justified when its energy balance is positive. The greatest increase in the methane yield per dry matter (12.4%) was observed after the extrusion of maize straw silage at 175 °C. The change in the methane yield resulting from the extrusion of maize silage and maize straw silage at 150 °C was small and amounted to 6.4% and 9%, respectively. The comminution caused an increase in the methane yield and accelerated the fermentation of substrates. The methane yield from maize silage was 38.4%, whereas the yield from maize straw silage was only 8.3%

Towards Operator-managed P2P Content Delivery with Application Layer Traffic Optimization

P2P technology provides a flexible and very popular way of content delivery for various services, including networked media applications. However, P2P-based content delivery generates large amount of backbone traffic. Recently, several approaches have been proposed for guiding P2P services based on operator preferences, in order to reduce the amount of costly backbone traffic generated by P2P applications. Application Layer Traffic Optimization (ALTO) is a one key approach for such managed P2P applications. In short, ALTO is a dedicated service, operated by a network operator or ISP, which can provide useful network layer information to application layer clients for improved peer selection and corresponding content delivery. This paper provides an overview of standardisation and research activities for improving P2P content delivery with ALTO which are carried out within the EU FP7 project NAPA-WINE. In particular, we give an overview on standardisation efforts, present simulation results, explain our prototypical implementation of the ALTO concept, and highlight ongoing large-scale operational trials we are currently conducting within the network of Polish Telecom and among NAPA-WINE partnersEU FP-7 NAPA-WIN

Experiences with large-scale operational trials of ALTO-enhanced P2P filesharing in an intra-ISP scenario

Application Layer Traffic Optimization (ALTO) has recently gained attention in the research and standardisation community as a way for a network operator to guide the peer selection process of distributed applications by providing network layer topology information. In particular P2P applications are expected to gain from ALTO, due to the many connections peers form among each other, often without taking network layer topology information into account. In this paper, we present results of an extensive intra-ISP trial with an ALTO-enhanced P2P filesharing software. In summary, our results show that—depending on the concrete setting and on the distribution of upload capacity in the network—ALTO enables an ISP to save operational costs significantly while not degrading application layer performance noticeably. In addition, based on our experience we are able to give advice to operators on how to save costs with ALTO while not sacrificing application layer performance at all

Mechanical thrombectomy in acute stroke : five years of experience in Poland

Objectives: Mechanical thrombectomy (MT) is not reimbursed by the Polish public health system. We present a description of 5 years of experience with MT in acute stroke in Comprehensive Stroke Centers (CSCs) in Poland. Methods and results: We retrospectively analyzed the results of a structured questionnaire from 23 out of 25 identified CSCs and 22 data sets that include 61 clinical, radiological and outcome measures. Results: Most of the CSCs (74%) were founded at University Hospitals and most (65.2%) work round the clock. In 78.3% of them, the working teams are composed of neurologists and neuro-radiologists. All CSCs perform CT and angio-CT before MT. In total 586 patients were subjected to MT and data from 531 of them were analyzed. Mean time laps from stroke onset to groin puncture was 250 99 min. 90.3% of the studied patients had MT within 6 h from stroke onset; 59.3% of them were treated with IV rt-PA prior to MT; 15.1% had IA rt-PA during MT and 4.7% - emergent stenting of a large vessel. M1 of MCA was occluded in 47.8% of cases. The Solitaire device was used in 53% of cases. Successful recanalization (TICI2b–TICI3) was achieved in 64.6% of cases and 53.4% of patients did not experience hemorrhagic transformation. Clinical improvement on discharge was noticed in 53.7% of cases, futile recanalization - in 30.7%, mRS of 0–2 - in 31.4% and mRS of 6 in 22% of cases. Conclusion: Our results can help harmonize standards for MT in Poland according to international guideline