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ObjectiveTo assess the short-term risk of acute myocardial infarction (AMI) associated with procedures performed at outpatient specialised hospital clinics.MethodsIn this case-crossover, population-based study, we identified first-time AMI cases aged ≥40 years via patient registries and linked them to their surgical intervention in Norway (2008–2016) and Sweden (2001–2014), respectively. The number of individuals with AMI who underwent procedures 0–7 days (hazard period) prior to the AMI diagnosis was compared with cases who were exposed 29–36 days (control period) before the AMI. A total of 6176 patients with AMI who underwent a procedure either during the defined hazard or control period contributed to the analyses. ORs with 95% CIs were computed using conditional logistic regression.ResultsThe mean age of the total population was 74.7 years and 64.6% were male. The relative risk was higher following procedures performed under general/regional anaesthesia for gastrointestinal endoscopy (ORsummary, 4.23, 95% CI 1.58 to 11.31), vascular (ORsummary, 3.12, 95% CI 1.10 to 8.90), urological/gynaecological (ORsummary, 2.30, 95% CI 1.50 to 3.53) and orthopaedic (ORsummary,1.78, 95% CI 1.30 to 2.44) procedures, and for ENT (ear, nose and throat) and mouth procedures (ORsummary,1.53, 95% CI 1.19 to 1.99) performed under local anaesthesia.ConclusionThis large population-based register study from two countries suggests that outpatient procedures are generally safe with regard to the postoperative risk of AMI. However, some procedures, such as gastrointestinal endoscopy, vascular procedures and urological/gynaecological procedures may increase the risk of AMI by twofold or threefold within the first 8 days after the procedures. Further studies are warranted to assess whether the effect is modified by cardiovascular medication or other clinical factors.

Open surgical repair (OSR) of descending and thoracoabdominal aortic aneurysms carries risks of mortality and major complications. Patients with connective tissue disorders (CTD) are younger and require safe, efficient treatment with long-term durability. This study provides current outcome data to help inform treatment decisions.All OSRs of descending thoracic aortic aneurysm (DTAA) or thoracoabdominal aortic aneurysm (TAAA) from January 2011 to July 2021 were included in a retrospective cohort study. Primary outcome measures were early and follow-up mortality and reintervention. Secondary outcome measures were major complications. Kaplan-Meier methods were used to estimate reintervention-free survival.A total of 26 OSRs (7 DTAA, 19 TAAA) were performed in 23 patients: 20 (77%) Marfan and 6 (23%) Loeys-Dietz syndrome; median age 43 years. Aortic dissection was present in 100% and 3/26 (12%) were urgent. Early mortality was 1/26 (3.8%). No patient suffered spinal cord ischemia, stroke, vocal cord paralysis, or re-exploration for bleeding. The transient respiratory failure occurred in 19% (5/26) and transient renal replacement therapy in 15% (4/26). Renal function normalized in all patients within 3 months. During follow-up (median 4.6, range 0-11 years) there were no deaths and only one re-intervention on a previously operated aortic segment, resulting in 92% reintervention-free survival at 5 years.In dedicated units, open surgical DTAA and TAAA repair in patients with CTD can be performed with a very low risk of death, severe complications and, late re-intervention. For CTD patients with reasonable risk, OSR should remain the first line of treatment.

Preoperative cardiovascular evaluations are frequently done before ambulatory ophthalmologic procedures. However, whether these procedures can trigger an acute myocardial infarction (AMI) is unknown.To assess the short-term risk for AMI associated with ophthalmologic procedures.Case-crossover design.Population-based nationwide study from Norway and Sweden.First-time patients with AMI, aged 40 years and older, identified via inpatient registries and linked to outpatient surgical procedures in Norway (2008 to 2014) and Sweden (2001 to 2014), respectively.Using self-matching, for each participant, exposure to ophthalmologic procedures in the 0 to 7 days before AMI diagnosis (hazard period) was compared with an 8-day period 30 days earlier, that is, days 29 to 36 before AMI (control period) to estimate the relative risk for an AMI the week after an ophthalmologic procedure. The odds ratios (ORs) with 95% CIs were calculated, using conditional logistic regression. Only patients who had a procedure of interest during either the hazard or control period were included.For the 806 patients with AMI included in this study, there was a lower likelihood of AMI in the week after an ophthalmologic procedure than during the control week (ORPotential bias from time-varying confounders between the hazard and the control periods.Ophthalmologic procedures done in an outpatient setting did not seem to be associated with an increased risk for AMI.Central Norway Regional Health Authority and the Swedish Research Council.

Dynamically-tunable reflective structural colors are attractive for reflective displays (electronic paper). However, it has been challenging to tune a thin layer of structural color across the full red-green-blue (RGB) basis set of colors at video rates and with long-term stability. Here, this is achieved through a hybrid cavity built from metal-insulator-metal (MIM) ‘nano-caves’ and an electrochromic polymer (PProDOTMe2). The reflective colors are modulated by electrochemically doping/dedoping the polymer. Compared with traditional subpixel-based systems, this hybrid structure provides high reflectivity (> 40%) due to its ‘monopixel’ nature, and switches at video rates. The polymer bistability helps deliver ultralow power consumption (~ 2.5 mW cm− 2) for video display applications and negligible values (~ 3 µW cm− 2) for static images, compatible with fully-photovoltaic powering. In addition, the color uniformity of the hybrid material is excellent (over cm− 2) and the scalable fabrication enables large-area production.

Bluetooth Low Energy (BLE) is one of the most important technologies that feed the growing field of Internet of Things and Wireless Sensor Networks. Due to its flexibility and unique low power-consumption, an increasing number of industrial devices, household appliances and wearables are being designed using it. However, the real-time demands of these networks such as timing and Quality of Service are not fully covered by the protocol itself. To help improve and offer some control over these characteristics, this paper presents a time slot transmission scheme with packet prioritization. It is based on the division and allocation of the connection interval to two types of messages: real-time and ordinary. The goal is to offer the lowest packet loss and time guarantees for real-time messages, while providing acceptable throughput for ordinary ones. Since the probability of a BLE connection to close increases with the number of packets sent through it, the position where a real-time packet is being sent as well as the number of ordinary messages in a connection represent key factors. The use of the first and last slot for real-time packets with ordinary flow restricted to the space between them decreases the transmission delay uncertainty and allows probability tuning based on the number of ordinary messages. Simulations were performed using the proposed scheme and a reduction of more than 100 times in the delay variance was observed for real-time transmissions. Regarding reliability, around 5% of the packets were lost for a bit error rate of $${10^{-3}}$$ .

Current European guidelines recommend both eversion CEA and conventional CEA with routine patch closure, rather thar routine primary closure. Polyester and polytetrafluoroethylene (PTFE) have been used as patch material for a long time. More recently, bovine pericardium has been used, however there are few studies comparing long-term results between bovine pericardium and other patch types. The aim of this study was to investigate the short- and long-term results after CEA depending on surgical technique and patch material.Registry-based study on all primary CEAs (n=9205) performed for symptomatic carotid artery stenosis in Sweden from July 2008 to December 2019, cross linked with data from the Swedish stroke registry, Riksstroke, and chart review for evaluation of any events occurring during follow-up. Primary endpoint was ipsilateral stroke30days. Secondary endpoints were reoperations due to neck haematoma and30day ipsilateral stroke30days, all stroke30days and all-cause mortality.2495 patients had undergone eversion CEA and 6710 conventional CEA for symptomatic carotid stenosis. The most commonly used patch-material was Dacron (n=3921), followed by PTFE (n=588) and Bovine pericardium (n=413). 1788 patients underwent conventional CEA with primary closure. 273 patients(3.0%) had a stroke30days. Primary closure was associated with an increased risk of ipsilateral stroke and stroke or death30days, OR 1.7(95%CI1.2-2.4), p=0.002; and 1.5(95% CI 1.2-2.0) respectively. During follow up (median 4.2 years), 592 patients had any form of stroke and 1492 died. There was no significant difference in long term risk of ipsilateral stroke, all stroke or death depending on surgical technique or patch material.There was an increased risk of ipsilateral stroke30days in patients operated with primary closure compared to eversion-CEA and patch angioplasty. There was no difference between primary closure, different patch types or eversion after the perioperative phase.

Objective: The purpose of this study was to compare short- and mid-term outcomes of fenestrated-branched endovascular repair (F-BEVAR) of pararenal (PRAA)/thoracoabdominal (TAAA) aortic aneurysms in patients with or without prior endovascular/open (EVAR/OAR) infrarenal aortic repair. Methods: Data from consecutive F-BEVAR (2010–2019) at two high-volume aortic centers were retrospectively reviewed. Primary endpoints were technical success, 30-day mortality, and overall survival. Secondary endpoints included 30-day major adverse events (MAE), freedom from type I/III endoleaks, reinterventions, sac expansion, and target vessel (TV) primary patency. Results: A total of 222 consecutive patients were included for analysis; of these 58 (26.1%) had prior infrarenal repair (EVAR=33, OAR=25) and 164 (73.9%) had native PRAA/TAAA. At baseline, patients with prior infrarenal repair were older (mean age=75.1 vs 71.6 years, p=.005) and the proportion of females was lower (8.6% vs 29.3%, p=.002). Technical success was 97.8% (n=217) in the entire cohort, without any significant differences between study groups (94.8% vs 98.8%, p=.08). At 30 days, there were no significant differences between patients with prior infrarenal repair as compared with those without in rate of MAE (44.8% vs 54.9%, p=.59). The 5-year estimate of survival for those who underwent native aortic repair was 61.6%, versus 61.3% for those who had a previous repair (p=.67). The 5-year freedom from endoleaks I/III estimates were significantly lower in patients who had prior infrarenal repair as compared with patients undergoing treatment of native aneurysms (57.1% vs 66.1%, p=.03), mainly owing to TV-related endoleaks (ie, type IC and/or IIIC endoleaks). No significant differences were found between study groups in rates of reinterventions and TV primary patency. Five-year estimates of freedom from sac increase >5mm were significantly lower in patients who received F-BEVAR after previous infrarenal repair as compared with those who underwent treatment of native aneurysms (48.6% vs 77.5%, p=.002). Conclusions: F-BEVAR is equally safe and feasible for treatment of patients with prior infrarenal repair as compared with those undergoing treatment for native aneurysms. Increased rates of TV-related endoleaks were observed which could lead to lower freedom from aneurysm sac shrinkage during follow-up. Nevertheless, the 5-year rates of reinterventions and TV patency were similar, thereby indicating that overall effectiveness of treatment remained satisfactory at mid-term.

Aims To compare stroke incidence in people with type 2 diabetes (T2D) with that in a matched control group, and to investigate whether glucose exposure in people with T2D can predict a first-time stroke event and mortality. Material and methods In a nationwide observational cohort study, individuals with T2D were linked in the Swedish National Diabetes Register and matched with five individual population-based control subjects. We calculated crude incidence rates and 95% confidence intervals (CIs), and used Cox regression and multivariable hazard ratios (HRs), to estimate the risk of stroke and mortality in relation to glycated haemoglobin (HbA1c) levels. Results A total of 406 271 people with T2D (age 64.1 ± 12.4 years, 45.7% women) and 2086 440 control subjects (age 64.0 ± 12.4 years, 45.7% women) were included. During a median follow-up of 7.3 years, 26 380 people with T2D (6.5%) versus 92 375 control subjects (4.4%) were diagnosed with a stroke. The incidence rate was 10.12 events per 1000 person-years versus 7.26 events per 1000 person-years (HR 1.54, 95% CI 1.52-1.56). In the T2D group after multivariable adjustments, the HRs for stroke stratified by HbA1c level were: 54-64 mmol/mol: 1.27 (95% CI 1.22-1.32); 65-75 mmol/mol: 1.68 (95% CI 1.60-1.76); 76-86 mmol/mol: 1.89 (95% CI, 1.75-2.05); and > 87 mmol/mol: 2.14 (95% CI 1.90-2.42), respectively, compared with the reference category of HbA1c ≤53 mmol/mol. There was a stepwise increased risk of death after stroke, for every 10-mmol/mol categorical increment of HbA1c (HR 1.71; 95% CI 1.47-2.00) for the highest HbA1c category. Conclusions An increased risk of stroke and death was associated with poor glycaemic control in people with T2D.

Relaying can increase reliability, range, or throughput. In many cyber-physical systems (CPS), relaying is used to maximize reliability before a given deadline. Since concurrent transmissions are not supported by most CPS, time-division multiple access (TDMA) is typically used. However, a major drawback of relaying in TDMA is that pre-allocated time-slots are wasted if their respective transmitters do not have any correctly received packet to relay. Therefore, in this letter, we propose a novel relay grouping scheme to overcome this drawback. Numerical results show that the proposed scheme significantly enhances the reliability while guaranteeing the deadline for each message.

Radiative cooling passively removes heat from objects via emission of thermal radiation to cold space. Suitable radiative cooling materials absorb infrared light while they avoid solar heating by either reflecting or transmitting solar radiation, depending on the application. Here, we demonstrate a reflective radiative cooler and a transparent radiative cooler solely based on cellulose derivatives manufactured via electrospinning and casting, respectively. By modifying the microstructure of cellulose materials, we can control the solar light interaction from highly reflective (>90%, porous structure) to highly transparent (≈90%, homogenous structure). Both cellulose materials show strong thermal emissivity and minimal solar absorption, making them suitable for daytime radiative cooling. Used as coatings on silicon samples exposed to sun light at daytime, the reflective and transparent cellulose coolers could passively reduce sample temperatures by up to 32 °C and 15 °C, respectively.

Objective Aortic prosthesis infection is a devastating complication of aortic surgery. In situ reconstruction with the neo-aorto-iliac system (NAIS) bypass technique has become increasingly used and is recommended in recent treatment guidelines. The main aim was to evaluate NAIS procedural outcomes when undertaken after previous open or endovascular aortic repair in Sweden. Methods In this retrospective study, The National Quality Registry for Vascular Surgery (Swedvasc) was used to identify Swedish centres that offered the NAIS bypass procedure for aortic prosthesis infection between 2008 and 2018. Variables of special interest were procedural details, short and long term survival, renal and other complications, and the durtion of antimicrobial treatment. Results Forty patients (36 males, four females [mean age 69 years], 32 open repairs, seven endovascular aortic repairs [EVAR] and one fenestrated EVAR; 21 presented with aorto-enteric fistula) operated on with NAIS bypass were reviewed. The median time from the primary aortic intervention to the NAIS bypass procedure was 32 months (range 0 – 252 months). Mean ± standard deviation operating time was 645 ± 160 minutes, mean blood loss was 6 277 ± 6 525 mL, mean length of intensive care unit stay was 5.3 ± 3.7 days, and mean length of overall hospital stay was 21.2 ± 11.4 days. Thirty-five patients (88%) had a positive microbial culture; the most commonly isolated pathogen was Candida spp. The majority of patients survived for 30 days (n = 35 [88%]), and 33 (83%) and 32 (80%) patients survived for 90 days and one year, respectively. The number of surviving patients free from antimicrobial treatment at 90 days, six months, and one year was 19 (58%), 29 (88%), and 30 (94%). After a mean long term follow up of 69.9 ± 44.7 months, 20 patients were still alive. Conclusion The NAIS bypass procedure offered reasonable survival and functional outcomes, and was associated with a high cure rate, defined as freedom from any antimicrobial treatment.

The seminal vesicle secretions of guinea pig and rabbit were analyzed for semen coagulum proteins. Using SDS-PAGE we discovered a previously not fully recognized semen coagulum protein, Svp5, in the guinea pig and a single predominant component, SVP200, in the rabbit. Potential genes of these proteins were identified in genome databases by their homology with human and murine genes. The structure of their fullength transcripts was determined using seminal vesicle cDNA and sequencing primers based on genomic sequences. Homology searching indicated that both Svp5 and SVP200 were synthesized from composite genes that were the result of merger between two genes showing homology with human SEMG2 and PI3. For a deeper understanding of the evolution of the genes, we retrieved and analyzed genome sequences from the REST gene loci, encompassing genes of semen coagulum proteins and related rapidly evolving seminal vesicle-transcribed genes, of 14 rodents and 2 lagomorphs. The analysis showed that rodents of the suborders myomorpha, hystricomorpha, and castorimorpha had unique sets of REST genes, whereas sciuromorpha seemed to be lacking such genes. It also indicated a closer relationship between myomorpha and castorimorpha than to rodents of the two other analyzed suborders. In the lagomorph species, the pika appeared to be devoid of REST genes, whereas the rabbit had a single expressed REST gene, SVP200, and two pseudogenes. The structural similarity of semen coagulum proteins in rabbit and hystricomph species suggests that they are closely related. This was also supported by other similarities at their REST gene loci, e.g. the finding of a PI3-like gene in the rabbit that also had features in common with caltrin2 of hystricomorph rodents. The homologies indicate that hystricomorpha may have separated from myomorpha and castorimorpha before the separation of hystricomorpha from lagomorpha.

Objective: Recent randomised controlled trials demonstrated the benefit of intracranial endovascular thrombectomy (EVT) in acute ischaemic stroke. There is no consensus, however, on how to treat concomitant extracranial carotid artery stenosis after EVT. The aim of this study was to evaluate the outcome in patients treated with carotid endarterectomy (CEA) after EVT, comparing complication rates among patients undergoing CEA for stroke without previous EVT. Methods: This was a registry study of all patients (n = 3 780) treated with CEA after stroke in Sweden and the capital Helsinki region, Finland, from January 2011 to September 2020. Sixty three patients (1.7%; 0.5% 2011, 4.3% 2019) underwent EVT prior to CEA. The primary outcome was 30 day stroke and death rate. Results: The EVT+CEA group had major stroke as the qualifying neurological event (QNE) in 79%, but just 5.9% had this in the CEA only group (p < .001). Intravenous thrombolysis was administered before EVT in 54% of patients in the EVT+CEA group, but in just 12% in those receiving CEA only (p < .001). The combined stroke and death rate at 30 days for EVT+CEA was 0.0% (95% confidence interval [CI] 0.0 - 5.7). One patient had a post-operative TIA, none had post-operative intracerebral or surgical site haemorrhage. CEA was performed within a median of seven days (interquartile range 4, 15) after QNE, and 75% had CEA

Cooperative awareness on the road is intended to support the road users by providing knowledge about the surroundings and relies on the information exchange enabled by vehicular communications. To achieve this goal the European telecommunication standard institute (ETSI) delivered the standard EN 302 637-2 for cooperative awareness messages (CAM). The CAM triggering conditions are based on the kinematics of the originating vehicle, which is checked periodically. In this paper, we show that the standardized ETSI protocol may suffer a decrease in communication performance under several realistic mobility patterns. The potential influence of the discovered phenomena on the IEEE 802.11p medium access control operation is studied. This work was partially supported by the Excellence Center at Linkoping-Lund in Information Technology (ELLIIT) strategic research environment (Sweden), NFITS - National ITS Postgraduate School (Sweden) and the ”ACDC: Autonomous Cooperative Driving: Communications Issues” project (2014-2016) funded by the Knowledge Foundation (Sweden) in cooperation with Volvo GTT, Volvo Cars, Scania, Kapsch TrafficCom and Qamcom Research & Technology.

Hollow ultra-low-density thermoplastic microspheres can be used as filler in elastic waterproof coatings to improve a number of important properties of the coatings. The hollow microspheres help reflect solar radiation and reduce the temperature in cool roof coatings. This can improve the indoor climate of buildings without air conditioning, or save energy by reducing the need for air conditioning. The mechanism for the reflection is described in this paper and is compared with the mechanism for reflection by pigment particles like titanium dioxide (TiO2). Results from solar reflection measurements show that the coating system filled with hollow microspheres reflects solar radiation of all incoming wavelengths, which is different from how TiO2 reflects light. The number of reflecting units is still important for the total solar reflection and suggests that the average size of the microspheres should be as small as possible. Like most other fillers, hollow low-density thermoplastic microspheres can be used in combination with pigments.

Leading network resilience researchers took part in the Resilience Week on Sept. 12-15, 2016 at Halmstad University, SE by Prof. Magnus Jonsson from the Centre for Research on Embedded Systems (CERES), Halmstad University, SE, and Prof. Jacek Rak from Gdansk University of Technology, PL. It included two major events: - The 2nd Meeting of COST CA15127–RECODIS Action (Resilient Communication Services Protecting End-user Applications from Disaster-based Failures, http://www.cost-recodis.eu) held on Sept. 12-13, 2016. - RNDM 2016-8th International Workshop on Resilient Networks Design and Modeling on Sept. 13-15, 2016.

High-performance embedded systems running real-time applications demand communication solutions providing high data rates and low error probabilities, properties inherent to optical solutions. However, providing timing guarantees for deadline bound applications in this context is far from basic due to the parallelism inherent in multiwavelength networks and often bound to include a large amount of pessimism. Assuming deterministic medium access, an admission control algorithm using a schedulability analysis can ensure deadline guarantees for real-time communication. The traffic dependency analysis presented in this paper is specifically targeting a multichannel context, taking into consideration the possibility of concurrent transmissions in these types of networks. Combining our analysis with a feasibility analysis in admission control, the amount of guaranteed hard real-time traffic could be shown to increase by a factor 7 in a network designed for a radar signal processing case. Using this combination of analysis methods will render possible an increased amount of hard real-time traffic over a given multichannel network, leading to a more efficient bandwidth utilization by deadline dependent applications without having to redesign the network or the medium access method.

Vehicular ad hoc networks (VANETs) have recently gained noticeable attention due to advantages in improving road traffic safety, shaping the road traffic and providing infotainment opportunities to travellers. However, transmission characteristics following from the IEEE 802.11p standard and the high mobility of VANET nodes remarkably reduce the lifetime, reach and capacity of wireless links, and often lead to simultaneous disruptions of communications at multiple links. In this chapter, we present a set of solutions to enhance the performance of VANETs (which can be applied independently of particular applications) concerning (a) design of the VANET infrastructure (location of road-side units—RSUs and gateways), (b) communications along vehicle-to-infrastructure (V2I) links and (c) resilience of VANET services to malicious human activities.

As one of the promising branches of the Internet of Things, the cloud-enabled Internet of Vehicles (CE-IoV) is envisioned to serve as an essential data sensing, exchanging, and processing platform with powerful computing and storage capabilities for future intelligent transportation systems. The CE-IoV shows great promise for various emerging applications. In order to ensure uninterrupted and high-quality services, a vehicle should move with its own VM via live VM migration to obtain real-time location-based services. However, the live VM migration may lead to unprecedented location privacy challenges. In this article, we study location privacy issues and defenses in CE-IoV. We first present two kinds of unexplored VM mapping attacks, and thus design a VM identifier replacement scheme and a pseudonym-changing synchronization scheme to protect location privacy. We carry out simulations to evaluate the performance of the proposed schemes. Numerical results show that the proposed schemes are effective and efficient with high quality of privacy.

Communication Technologies for Vehicles : 14th International Workshop, Nets4Cars/Nets4Trains/Nets4Aircraft 2019, Colmar, France, May 16–17, 2019, Proceedings

Vehicular ad hoc networks (VANETs) can provide safety and nonsafety applications to improve passenger safety and comfort. Grouping vehicles into platoons in VANETs can improve road safety and reduce fuel consumption. It is critical to design an efficient medium access control (MAC) protocol for platoon-based VANETs. Moreover, because of the space and time dynamics of moving vehicles, network connectivity is an important performance metric to indicate the quality of the network communications and the satisfaction of users. Unfortunately, network connectivity is often ignored in the design of existing MAC protocols for VANETs. In this paper, we study the connectivity characteristics and present a connectivity-aware MAC protocol for platoon-based VANETs. The connectivity probabilities are analyzed for vehicle-to-vehicle and vehicle-to-infrastructure communication scenarios in one- and two-way VANETs, respectively. A multipriority Markov model is presented to derive the relationship between connectivity probability and system throughput. Based on variable traffic status and network connectivity, a multichannel reservation scheme is adopted to dynamically adjust the length of the control channel interval and the service channel interval for the improvement of the system throughput. Analysis and simulation results show that the throughput increases with connectivity probability. However, with a further increase in connectivity probability, the throughput will decrease due to numerous channel contentions.

Autonomous driving in road trains, a.k.a. platooning, may reduce fuel consumption considerably if the intervehicle distances are kept short. However, to do this, the intraplatoon communication must not only be reliable but also able to meet strict deadlines. While time-triggered messages are the foundation of most distributed control applications, platooning is likely to also require dissemination of event-driven messages. While much research work has focused on minimizing the age of periodic messages, state-of-the-art for disseminating eventdriven messages is to let all nodes repeat all messages and focus on mitigating broadcast storms. We derive an efficient message dissemination scheme based on relay selection which minimizes the probability of error at the intended receiver(s) for both unicast and broadcast, without degrading the performance of co-existing time-triggered messages. We present a full analysis of the resulting error probability and delay, when relayers, selected by our algorithm, are used to disseminate messages within a platoon. Numerical results indicate that the proposed relaying policy significantly enhances the reliability for a given delay. ACDC

Cyclists are not well protected in accidents with other road users, and there are few active safety systems available for bicycles. In this study we have evaluated the use of inexpensive Real-Time Kinematic Satellite Navigation (RTK-SN) receivers with multiple satellite constellations together with dead reckoning for accurate positioning of bicycles to enable active safety functions such as collision warnings. This is a continuation of previous work were we concluded that RTK-SN alone is not sufficient in moderately dense urban areas as buildings and other obstructions degrade the performance of RTK-SN significantly. In this work we have added odometry to the positioning system as well as extending RTK-SN with multiple satellite constellations to deal with situations where the view of the sky is poor and thus fewer satellites are in view. To verify the performance of the positioning system we have used Ultra-Wideband radios as an independent positioning system to compare against while testing during poor conditions for RTK-SN. We were able to verify that adding dead reckoning and multiple satellite constellations improves the performance significantly under poor conditions and makes the positioning system more useful for active safety systems.

Communication networks have become a fundamental part of many critical infrastructures, playing an important role in information delivery in various failure scenarios triggered e.g., by forces of nature (including earthquakes, tornados, fires, etc.), technology-related disasters (for instance due to power blackout), or malicious human activities. A number of recovery schemes have been defined in the context of network resilience (with the primary focus on communication possibility in failure scenarios including access to a particular host, or information exchange between a certain pair of end nodes). However, because end-users are becoming more and more interested in information itself (regardless of its physical location in the network), it is appropriate to complement the well-defined framework of network resilience with one that addresses information resilience, and to introduce definitions of relevant disciplines and measures, as proposed in this paper.

In LTE/LTE-A the Discontinuous Reception (DRX) mechanism is the main approach for power saving in User Equipments (UEs) when in Connected and Idle mode. In this paper, an Idle mode DRX mechanism model is proposed also enabling evaluation of closely related mechanisms such as paging and Tracking Area Update (TAU). Two performance metrics are derived, namely the reachability delay and the power saving factor.

Prospective IEEE 802.11p-based vehicular surveillance system, where video from the vehicle on-board camera is transmitted to the management center, is considered. Multi-hop transmission from the vehicle to the nearest roadside unit and then — via other roadside units — to the gateway is addressed. In this letter we assess the feasibility of such system by analyzing the video end-to-end distortion for a target vehicle, located several hops away from the gateway, when it is alone or there are also other vehicles transmitting video. We demonstrate the importance of dynamic adaptation of the video bit rate of each vehicle depending on the number and positions of the participating vehicles.

Replacement intervals of implantable medical devices are commonly dictated by battery life. Therefore, intracorporeal energy harvesting has the potential to reduce the number of surgical interventions by extending the life cycle of active devices. Given the accumulated experience with intravascular devices such as stents, heart valves, and cardiac assist devices, the idea to harvest a small fraction of the hydraulic energy available in the cardiovascular circulation is revisited. The aim of this article is to explore the technical feasibility of harvesting 1 mW electric power using a miniature hydrodynamic turbine powered by about 1% of the cardiac output flow in a peripheral artery. To this end, numerical modelling of the fluid mechanics and experimental verification of the overall performance of a 1:1 scale friction turbine are performed in vitro. The numerical flow model is validated for a range of turbine configurations and flow conditions (up to 250 mL/min) in terms of hydromechanic efficiency; up to 15% could be achieved with the nonoptimized configurations of the study. Although this article does not entail the clinical feasibility of intravascular turbines in terms of hemocompatibility and impact on the circulatory system, the numerical model does provide first estimates of the mechanical shear forces relevant to blood trauma and platelet activation. It is concluded that the time-integrated shear stress exposure is significantly lower than in cardiac assist devices due to lower flow velocities and predominantly laminar flow.

A method for real-time detection of Denial-of-Service (DoS) attacks in IEEE 802.11p vehicular ad-hoc networks (VANETs) is proposed. The study is focused on the "jamming" of periodic position messages (beacons) exchanged by vehicles in a platoon. Probabilities of attack detection and false alarm are estimated for two different attacker models.

Functionalization of thermally expandable microspheres (TEMs) with a conjugated polymer is explored. These functionalized thermally expandable microspheres were prepared by grafting 3-n-dodecylthiophene via oxidative polymerization from a thiophene modified TEM. The thiophene modified TEM to 3-n-dodecylthiophene ratio was varied during grafting and the resulting poly(3-n-dodecylthiophene) grafted TEM were characterized by FT-IR spectroscopy, Thermal Gravimetric Analysis, Scanning Electron Microscopy, Thermo-Mechanical Analysis and X-ray diffraction. The particles were approximately 30 μm in diameter and upon heating, the functionalized microspheres expanded up to 50 times. This expansion property was related to the poly(3-n-dodecylthiophene) content, where the increase in poly(3-n-dodecylthiophene) on microsphere decreased the thermal expansion. The X-ray diffraction shows a sharpening of the poly(3-n-dodecylthiophene) (1 0 0) diffraction peak upon expansion. Grafting conjugated polymers to thermally expandable microspheres provides robust functional photo- and electro-active TEMs.

Many emerging applications based on wireless networks involve distributed control. This implies high requirements on reliability, but also on a predictable maximum delay and sometimes jitter. Further, many distributed control systems need to be constructed using off-the-shelf components, both due to cost constraints and due to interoperability with existing networks. This, in turn, implies that concurrent transmissions and multiuser detection are seldom possible. Instead, half-duplex time division multiple access (TDMA) is typically used. The total communication delay thereby depends on the packet error rate and the time until channel access is granted. With TDMA, channel access is upper-bounded and the jitter can be set to zero. With the aim to reduce the packet error rate given a certain deadline (a set of TDMA time-slots), we propose a novel relaying scheme, which can be implemented on top of off-the-shelf components. The paper includes a full analysis of the resulting error probability and latency. Numerical results show that the proposed relaying strategy significantly improves reliability given a certain maximum latency, or alternatively, reduces the latency, given a certain target reliability requirement.

Inter-vehicular communications is seen as a promising solution to a number of issues related with public road safety, road congestion management, and infotainment. However, Vehicular Ad-hoc NETworks (VANETs) characterized by high mobility of vehicles and facing a number of other issues related with high frequency wireless communications and network disconnections, encounter major challenges related with reliability of message delivery. This issue, despite a number of relevant publications, has not been extensively researched so far. This paper is the first one to provide a definition of information resilience for VANETs and the respective taxonomy of challenges to resilient message delivery for all types of VANET applications (being adaptation of a general taxonomy of challenges for networked systems). Example challenges related to technical aspects of resilient message dissemination for PHY/MAC layer, broadcast transmission, and multi-hop routing are outlined in the final part of the paper.

Objectives The aim was internal vascular centre quality-control measures to compare single-centre results with the national perspective, as well as analysing the Swedish results from carotid artery stenting (CAS) and comparing a relatively high-volume single centre with the Swedish Vascular Registry (Swedvasc) data. The second aim was to compare CAS and carotid artery endarterectomy (CEA) outcomes for the same 7-year period. Design Retrospective review of a single high-volume centre (Sodersjukhuset (SOS)) (approximately 30 CAS year −1 approximately 90 CEA year −1 ) versus Swedvasc National data. Materials and methods All consecutive selective patients treated with CAS at SOS for a stenosis of the internal carotid artery ( n = 208) or CEA ( n = 552) between 2004 and 2011 were compared with all patients in Swedvasc registered for CAS ( n = 258) and CEA ( n = 6474). Primary outcome was 30-day frequency of stroke or death. Secondary outcome was stroke/death/acute myocardial infarction (AMI). Results The 30-day frequency of any stroke or death after CAS at SOS compared to the national data was 2.9% and 7.4%, respectively ( P = 0.04). The 30-day AMI/stroke/death frequency was 3.4% and 9.5%, respectively ( P = 0.01). After CEA during the same time period, the Swedvasc national data had a 4.4% frequency of 30-day stroke and death and 5.8% for AMI/stroke/death. Conclusions CAS is not as safe as CEA from a national perspective but our results indicate that a single centre can achieve acceptable results with CAS.

The implementation of ITS (Intelligent Transport Systems) services offers great potential to improve the level of safety, efficiency and comfort on our roads. Although cooperative traffic safety applications rely heavily on the support for real-time communication, the Medium Access Control (MAC) mechanism proposed for the upcoming IEEE 802.11p standard, intended for ITS applications, does not offer deterministic real-time support, that is, the access delay to the common radio channel is not upper bounded. To address this problem, we present a framework for a vehicle-to-infrastructure-based (V2I) communication solution extending IEEE 802.11p by introducing a collision-free MAC phase assigning each vehicle an individual priority based on its geographical position, its proximity to potential hazards and the overall road traffic density. Our solution is able to guarantee the timely treatment of safety-critical data, while minimizing the required length of this real-time MAC phase and freeing bandwidth for best-effort services (targeting improved driving comfort and traffic efficiency). Furthermore, we target fast connection setup, associating a passing vehicle to an RSU (Road Side Unit), and proactive handover between widely spaced RSUs. Our real-time MAC concept is evaluated analytically and by simulation based on a realistic task set from a V2I highway merge assistance scenario. Copyright © 2011 Annette Böhm and Magnus Jonsson. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Thermally expandable microspheres are polymeric core/shell particles in which a volatile hydrocarbon is encapsulated by a thermoplastic shell. When these microspheres are heated, they expand and increase their volume dramatically. This volume increase is retained upon cooling, leading to a density reduction from around 1100 kg m-3 to about 30 kg m-3. Since the development in the early 1970´s, microspheres have been used extensively by the industry as a foaming agent or light weight filler. In this thesis, microspheres with a poly(acrylonitrile-co-methacrylonitrile) shell have been synthesized through free radical suspension polymerization. The microspheres have been characterized with respect to particle morphology and expansion properties in order to deepen the understanding of the microspheres. It was found that the monomer feed ratio and the polymerization temperature are very important parameters with respect to the expansion properties. Excellent expansion could only be accomplished when polymerizing at 62 °C, with the acrylonitrile feed, fAN, being around 60 mol%, even though core/shell microspheres are formed over a much wider range of fAN. Furthermore, no expansion was achieved when polymerizing at 80 °C, even though no noticeable differences were found, compared to the corresponding sample polymerized at 62 °C. It was also shown that the expansion properties can be modified by replacing the encapsulated hydrocarbon by another hydrocarbon with a different boiling point. Not only is the boiling point important, the structure of the hydrocarbon is also important. Isooctane which is highly branched was found to give superior expansion compared to linear or cyclic hydrocarbons having a similar boiling point. Crosslinking of the polymer shell has proven to be very important for the expansion properties. Both the amount and the structure of the crosslinker are important parameters. Especially the maximum expansion can be improved by the crosslinking of the polymer shell. This originates in an increase in the shape persistence of the expanded microspheres at elevated temperatures. By the combination of crosslinkers that are incorporated separately into the polymer shell, the onset temperature of expansion can be increased significantly. Finally, the surface of microspheres has been modified by grafting poly(glycidyl methacrylate) from the surface by ARGET ATRP. Given that the reaction conditions are appropriate, such modifications can be performed with only limited effects on the expansion properties of the microspheres.

4. Februar 2010, das Hauptquartier von Volvo Cars in Goteborg. Zum Zeitpunkt des Treffens mit Magnus Jonsson deutet alles darauf hin, dass die schwedische Marke vom chinesischen Autobauer Geely gekauft wird. Nur, uber ungelegte Eier redet sich schlecht - und naturlich gibt es reichlich andere Themen, die den Entwicklungschef beschaftigen, nicht zuletzt: Sicherheit.

This study demonstrates the surface modification of thermally expandable core/shell microspheres by grafting glycidyl methacrylate (GMA) using activators regenerated by electron transfer (ARGET) ATRP. To retain the expansion properties it was essential to minimize the shear forces, use solvents compatible with the microspheres and keep the reaction times short (three hours or less). Using microspheres with hydroxyl groups on the surface, it was found that after converting these to α-bromo esters, GMA could be grafted by ARGET ATRP using only 50 ppm of copper catalyst in toluene at 30 °C. Decent control of the polymerization was achieved with PMDETA as ligand reaching PDIs of 1.4 for the solution polymerization of GMA. When microspheres were present, the polymerization was less controlled with higher PDIs. The epoxide groups of the grafted microspheres were hydrolyzed by HCl in THF providing a hydrophilic surface of the microsphere. The expansion property of the microspheres was studied after each reaction step by thermal mechanical analysis, and it was found that the expansion capacity was well preserved with only limited negative effect on the microspheres.

Vicia pisiformis L. is a perennial leguminous plant with a main distribution in broadleaved forest-steppes of eastern Europe. The species is classified as endangered (EN) according to the IUCN red- ...

Background and Purpose— Long-term outcome after carotid artery stenting (CAS), a less invasive technique than carotid endarterectomy (CEA), for prevention of stroke, is unclear. The aim was to assess long-term outcomes after CAS, compared with CEA, in a nationwide cohort study. Methods— All patients registered in the national Swedish Vascular Registry (Swedvasc) treated with primary CAS between 2005 and 2012 were identified. For every CAS, 2 CEA controls, matched for sex, age, procedure year, and indication (symtomatic/asymtomatic), were chosen. Postoperative stroke was identified by cross-matching the cohort with the InPatient Registry and charts review. Primary end point was ipsilateral stroke or death >30 days postoperatively. Results— A total of 1157 patients were included, 409 CAS and 748 CEA; 73% men with mean age 70 years and 69% were symptomatic. Risk factor profile was similar between the 2 groups. Median follow-up time was 4.1 years. Ipsilateral stroke or death of >30 days postoperatively occurred in 95 of 394 in the CAS group versus 120 of 724 in the CEA group (adjusted hazard ratio, 1.59; 95% confidence interval, 1.15–2.18). The corresponding adjusted rates for death, ipsilateral stroke of >30 days, and any stroke or death of >30 days were 25.7% versus 18.6% (hazard ratio, 1.20; 95% confidence interval, 0.84–1.72), 9.4% versus 2.9% (hazard ratio, 3.40; 95% confidence interval, 1.53–7.53), 34.2% versus 23.6% (hazard ratio, 1.49; 95% confidence interval, 1.10–2.00) for the CAS group versus CEA group, respectively. Conclusions— In this nationwide cohort study, CAS was associated with an increased long-term risk of ipsilateral stroke and death during after the perioperative phase when compared with CEA.