Secret key exchange in ultra-long lasers by radio-frequency spectrum coding

We propose a new approach to the generation of an alphabet for secret key exchange relying on small variations in the cavity length of an ultra-long fiber laser. This new concept is supported by experimental results showing how the radio-frequency spectrum of the laser can be exploited as a carrier to exchange information. The test bench for our proof of principle is a 50 km-long fiber laser linking two users, Alice and Bob, where each user can randomly add an extra 1 km-long segment of fiber. The choice of laser length is driven by two independent random binary values, which makes such length become itself a random variable. The security of key exchange is ensured whenever the two independent random choices lead to the same laser length and, hence, to the same free spectral range

Estimating Level of Engagement from Ocular Landmarks

E-learning offers many advantages like being economical, flexible and customizable, but also has challenging aspects such as lack of – social-interaction, which results in contemplation and sense of remoteness. To overcome these and sustain learners’ motivation, various stimuli can be incorporated. Nevertheless, such adjustments initially require an assessment of engagement level. In this respect, we propose estimating engagement level from facial landmarks exploiting the facts that (i) perceptual decoupling is promoted by blinking during mentally demanding tasks; (ii) eye strain increases blinking rate, which also scales with task disengagement; (iii) eye aspect ratio is in close connection with attentional state and (iv) users’ head position is correlated with their level of involvement. Building empirical models of these actions, we devise a probabilistic estimation framework. Our results indicate that high and low levels of engagement are identified with considerable accuracy, whereas medium levels are inherently more challenging, which is also confirmed by inter-rater agreement of expert coders

Guidance on the management of left ventricular assist device (LVAD) supported patients for the non-LVAD specialist healthcare provider: executive summary

The accepted use of left ventricular assist device (LVAD) technology as a good alternative for the treatment of patients with advanced heart failure together with the improved survival of patients on the device and the scarcity of donor hearts has significantly increased the population of LVAD supported patients. Device-related, and patient-device interaction complications impose a significant burden on the medical system exceeding the capacity of LVAD implanting centres. The probability of an LVAD supported patient presenting with medical emergency to a local ambulance team, emergency department medical team and internal or surgical wards in a non-LVAD implanting centre is increasing. The purpose of this paper is to supply the immediate tools needed by the non-LVAD specialized physician - ambulance clinicians, emergency ward physicians, general cardiologists, and internists - to comply with the medical needs of this fast-growing population of LVAD supported patients. The different issues discussed will follow the patient's pathway from the ambulance to the emergency department, and from the emergency department to the internal or surgical wards and eventually back to the general practitioner.Cardiolog

HFA of the ESC Position paper on the management of LVAD supported patients for the non LVAD specialist healthcare provider Part 1: Introduction and at the non-hospital settings in the community.

The accepted use of left ventricular assist device (LVAD) technology as a good alternative for the treatment of patients with advanced heart failure together with the improved survival of the LVAD-supported patients on the device and the scarcity of donor hearts has significantly increased the population of LVAD-supported patients. The expected and non-expected device-related and patient-device interaction complications impose a significant burden on the medical system exceeding the capacity of the LVAD implanting centres. The ageing of the LVAD-supported patients, mainly those supported with the 'destination therapy' indication, increases the risk for those patients to experience comorbidities common in the older population. The probability of an LVAD-supported patient presenting with medical emergency to a local emergency department, internal, or surgical ward of a non-LVAD implanting centre is increasing. The purpose of this trilogy is to supply the immediate tools needed by the non-LVAD specialized physician: ambulance clinicians, emergency ward physicians, general cardiologists, internists, anaesthesiologists, and surgeons, to comply with the medical needs of this fast-growing population of LVAD-supported patients. The different issues discussed will follow the patient's pathway from the ambulance to the emergency department and from the emergency department to the internal or surgical wards and eventually to the discharge home from the hospital back to the general practitioner. In this first part of the trilogy on the management of LVAD-supported patients for the non-LVAD specialist healthcare provider, after the introduction on the assist devices technology in general, definitions and structured approach to the assessment of the LVAD-supported patient in the ambulance and emergency department is presented including cardiopulmonary resuscitation for LVAD-supported patients

HFA of the ESC position paper on the management of LVAD-supported patients for the non-LVAD specialist healthcare provider Part 3: at the hospital and discharge.

The growing population of left ventricular assist device (LVAD)-supported patients increases the probability of an LVAD- supported patient hospitalized in the internal or surgical wards with certain expected device related, and patient-device interaction complication as well as with any other comorbidities requiring hospitalization. In this third part of the trilogy on the management of LVAD-supported patients for the non-LVAD specialist healthcare provider, definitions and structured approach to the hospitalized LVAD-supported patient are presented including blood pressure assessment, medical therapy of the LVAD supported patient, and challenges related to anaesthesia and non-cardiac surgical interventions. Finally, important aspects to consider when discharging an LVAD patient home and palliative and end-of-life approaches are described

Heart Failure Association of the European Society of Cardiology position paper on the management of left ventricular assist device-supported patients for the non-left ventricular assist device specialist healthcare provider: Part 2: at the emergency department.

The improvement in left ventricular assist device (LVAD) technology and scarcity of donor hearts have increased dramatically the population of the LVAD-supported patients and the probability of those patients to present to the emergency department with expected and non-expected device-related and patient-device interaction complications. The ageing of the LVAD-supported patients, mainly those supported with the 'destination therapy' indication, increases the risk for those patients to suffer from other co-morbidities common in the older population. In this second part of the trilogy on the management of LVAD-supported patients for the non-LVAD specialist healthcare provider, definitions and structured approach to the LVAD-supported patient presenting to the emergency department with bleeding, neurological event, pump thrombosis, chest pain, syncope, and other events are presented. The very challenging issue of declaring death in an LVAD-supported patient, as the circulation is artificially preserved by the device despite no other signs of life, is also discussed in detail

Exploring spatial relationships : a strategy for guiding technological problem solving

The growing realization of the benefits to individual students and to state economies, of providing science learners with opportunities to expand their knowledge, skills and experience of knowledge-based technological design has led to seeking instructional strategies to facilitate the transition from traditional school settings to project based learning environments. This paper refers to engaging high school physics and computer-science majors in challenging design projects which seek to activate and implement the often inert formal content knowledge within the context of designing and constructing systems dealing with real world engineering challenges in robotics and electro-optics. In this paper we suggest that visualization of the problem space and guided exploration of its spatial relationships can promote the elicitation of relevant formal knowledge and lead to creative solution design. These methods are described in the context of designing and programming robot navigation and in the context of developing remote distance sensors