Consumo energético de algoritmos criptográficos y protocolos de seguridad en dispositivos móviles Symbian

En los últimos años, la telefonía móvil ha redenido la forma de comunicación entre las personas. Los dispositivos electrónicos, a través de los cuales se establece dicha comunicaci ón, han evolucionado vertiginosamente en potencia, rendimiento y sobre todo en nuevas funcionalidades, pero siguen estando limitados por la autonomía que les proporciona la duración de la batería. Mientras la capacidad de procesamiento se incrementa en un 200% cada 18 meses siguiendo la Ley de Moore, el rendimiento de las baterías sólo se ha visto mejorado en un 80% en los últimos 10 años [Fit07]. Esta mejora del rendimiento y la llegada de Internet a estos dispositivos ha hecho posible la comunicación a través de diferentes canales, la búsqueda de información o la posibilidad de realizar compras, todo ello de una forma segura y condencial. Dichas conexiones seguras, bien utilizando conexiones cableadas o inalámbricas, se consiguen mediante la utilización de protocolos de seguridad, basados en algoritmos criptográcos. Estos algoritmos son seleccionados basándose en los objetivos de seguridad denidos en el protocolo de seguridad a utilizar. Entre ellos se incluyen algoritmos de encriptación simétricos y asimétricos, utilizados para proporcionar autenticación y encriptación de los datos, así como algoritmos basados en funciones hash, y, de esa manera, conseguir integridad en los mensajes intercambiados. En la actualidad, el consumo energético en dispositivos móviles es una de los principales preocupaciones de los fabricantes de dispositivos móviles. De la misma manera, la seguridad en las comunicaciones se posiciona como una área muy importante en materia de investigación y desarrollo. El uso de protocolos de seguridad no sólo afecta al rendimiento de las comunicaciones, sino que también representa un fuerte impacto en el consumo energético en estos dispositivos alimentados por baterías. De este modo, uno de los desaf íos más importantes es conseguir un balance entre rendimiento, seguridad y consumo energético, con el n de obtener un buen rendimiento y niveles de seguridad adaptados al usuario con la mínima cantidad de energía. En este contexto, Nokia corporation encargó un proyecto de investigación a la Aalto University School of Science and Technology (Helsinki, Finlandia), para analizar el consumo energético de diferentes protocolos de seguridad y algoritmos criptográcos en la plataforma móvil Symbian

Human lactoferrin but not lysozyme neutralizes HSV-1 and inhibits HSV-1 replication and cell-to-cell spread

The frequent oral shedding of herpes simplex virus type 1 (HSV-1) in the absence of clinical disease suggests that symptomatic HSV-1 recurrences may be inhibited by the mucosal environment. Indeed, saliva has been shown to contain substances with anti-HSV activity. In the current study, we investigated the anti-HSV-1 activity of human lactoferrin (hLf) and lysozyme (hLz), two highly cationic polypeptides of the mucosal innate defence system

Association of Viral Load With Disease Severity in Outpatient Children With Respiratory Syncytial Virus Infection

Background. There are scarce data on whether viral load affects the severity of respiratory syncytial virus (RSV) disease in outpatient children.Methods. We analyzed the association between viral load and disease severity among children who participated in a prospective cohort study of respiratory infections. The children were examined and nasal swabs for the detection of RSV were obtained during each respiratory illness. Quantification of RSV load was based on the cycle threshold (Ct) value. For the primary analysis, the children were divided into 2 groups: higher (Ct = 27).Results. Among 201 episodes of RSV infection, children with higher viral load had significantly longer median durations of rhinitis (8 vs 6 days; P = .0008), cough (8 vs 6 days; P = .034), fever (2 vs 1 days; P = .018), and any symptom (10 vs 8 days; P = .024) than those with lower viral load. There were statistically significant negative correlations between the Ct values and durations of all measured symptoms.Conclusions. Our findings support the concept that viral load drives the severity of RSV disease in children. Reducing the viral load by RSV antivirals might provide substantial benefits to outpatient children.</p

The Relationship of Anxiety and Stress With Working Memory Performance in a Large Non-depressed Sample

Clinical anxiety and acute stress caused by major life events have well-documented detrimental effects on cognitive processes, such as working memory (WM). However, less is known about the relationships of state anxiety or everyday stress with WM performance in non-clinical populations. We investigated the associations between these two factors and three WM composites (verbal WM, visuospatial WM, and n-back updating performance) in a large online sample of non-depressed US American adults. We found a trend for a negative association between WM performance and anxiety, but not with stress. Thus, WM performance appears rather robust against normal variation in anxiety and everyday stress.Peer reviewe

Seasonality and geographical spread of respiratory syncytial virus epidemics in 15 European countries, 2010 to 2016

Respiratory syncytial virus (RSV) is considered the major pathogen causing severe lower respiratory tract infections among infants and young children [1]. RSV is the most common cause of hospitalisation for acute lower respiratory tract infection in children younger than 5 years and is estimated to cause between 66,000 and 199,000 deaths worldwide every year [2]. Its significance in causing substantial morbidity and hospitalisation in the first year of life has been affirmed in a recent study and a meta-analysis [3,4]. In England, average annual hospital admission rates are 35.1 per 1,000 children younger than 1 year and 5.31 per 1,000 children aged 1–4 years [5]. In addition to children, RSV causes a substantial disease burden in elderly people and patients with chronic obstructive pulmonary disease [6,7]. RSV causes seasonal epidemics worldwide [8], with one to two epidemics each year [9] following latitudinal gradients in timing, duration, seasonal amplitude and between-year variability [8,9]. In some studies, the seasonal periodicity has been connected to climatic factors [9-11], but a common factor that explains all observed periodicity has not been established. Meteorological conditions such as temperature and high relative humidity have been reported as important predictors of RSV epidemics [9,12]. In the United States (US) and Japan, annual national and regional variation of RSV season onset and end has been reported [13-15]. In the Nordic countries, a major outbreak often alternates with a minor one, with the minor peak in the spring and a major one the following winter [16-19], a phenomenon reported also in Croatia [20], Denmark [21] and Germany [22]. RSV antigenic groups A and B alternate in two-year cycles in Finland, with dominance of the group A viruses in years 1981–82, 1985–86 and 1989–90 and the group B viruses 1983–84 and 1987–88 [17,19], and different genotypes dominate the circulation in consecutive epidemics in Korea [23]. In Spain, no biennial rhythm has been detected but rather a stable annual epidemic with a peak between week 52 and week 1 and circulation 2–8 weeks earlier than influenza viruses [24]. Similarly, in the United Kingdom (UK), one stable epidemic per year is observed [5]. Immunoprophylaxis to prevent RSV infection with a neutralising monoclonal antibody, palivizumab, has been developed for administration to target groups on a monthly basis during the RSV season [25]. However, this drug is limited to high-risk infants, the cost prohibits its use in low- and middle-income countries and the data on effectiveness of the drug in children at high risk other than infants born at gestational age < 33 weeks and in children with chronic lung and heart diseases are limited [26]. The demonstrated high disease burden of RSV infection has created a longstanding interest in RSV vaccines. Approximately 60 RSV vaccine candidates are in preclinical to phase III clinical trials [27,28], with potential target groups including elderly people, pregnant women and infants. A vaccine is expected to enter the market within 5–10 years, presumably by 2025 [29]. As natural infection provides only limited protective immunity owing to evolution of the surface protein G and alternating dominance of antigenic groups A and B [30], most of the vaccine candidates target the fusion protein F, which is cross-reactive across RSV subtypes [27]. To circumvent issues with alternating strains, it has been also suggested to consider inclusion of both RSV A and B in a future RSV vaccine [30]. To plan optimal future vaccination strategies, it is critically important to understand who is affected by RSV and to identify which groups are at risk of more severe RSV infection requiring hospitalisation or intensive care. RSV infection is not notifiable in the European Union (EU) and European Economic Area (EEA), except in Ireland, but many countries have a long tradition of reporting laboratory-confirmed RSV infections at national and international level. The European Influenza Surveillance Network (EISN) collects RSV data for the purpose of interpreting the reports of influenza-like-illness (ILI); these data can also be used to analyse seasonality of RSV [31]. Inter-country comparative analysis of seasonal circulation of RSV across Europe is lacking as most of the published literature focuses on individual countries. Our study describes the seasonality of RSV in 15 countries in the EU/EEA, specifically the start and peak of the season, length of the season and geographical spread, as a baseline description of RSV circulation in Europe. We further aimed to test if the data reported through influenza surveillance systems in use in EU/EEA countries are appropriate to analyse RSV seasonality, including more countries and a more detailed analysis than previous studies.Peer Reviewe

The early effects of external and internal strategies on working memory updating training

The mechanisms underlying working memory training remain unclear, but one possibility is that the typically limited transfer effects of this training reflect adoption of successful task-specific strategies. Our pre-registered randomized controlled trial (N = 116) studied the early effects of externally given vs. internally generated strategies in an updating task (n-back) over a 5-day period with a single 30-minute training session. Three groups were employed: n-back training with strategy instruction (n = 40), n-back training without strategy instruction (n = 37), and passive controls (n = 39). We found that both external and internal strategy use was associated with significantly higher posttest performance on the trained n-back task, and that training with n-back strategy instruction yielded positive transfer on untrained n-back tasks, resembling the transfer pattern typically seen after the ordinary uninstructed 4-6-week working memory training. In the uninstructed participants, the level of detail and type of internally generated n-back strategies at posttest was significantly related to their posttest n-back performance. Our results support the view that adoption of task-specific strategies plays an important role in working memory training outcomes, and that strategy-based effects are apparent right at the start of training