Sporadic cloud-based mobile augmentation on the top of a virtualization layer: a case study of collaborative downloads in VANETs

Current approaches to Cloud-based Mobile Augmentation (CMA) leverage (cloud-based) resources to meet the requirements of rich mobile applications, so that a terminal (the so-called application node or AppN) can borrow resources lent by a set of collaborator nodes (CNs). In the most sophisticated approaches proposed for vehicular scenarios, the collaborators are nearby vehicles that must remain together near the application node because the augmentation service is interrupted when they move apart. This leads to disruption in the execution of the applications and consequently impoverishes the mobile users’ experience. This paper describes a CMA approach that is able to restore the augmentation service transparently when AppNs and CNs separate. The functioning is illustrated by a NaaS model where the AppNs access web contents that are collaboratively downloaded by a set of CNs, exploiting both roadside units and opportunistic networking. The performance of the resulting approach has been evaluated via simulations, achieving promising results in terms of number of downloads, average download times, and network overheadMinisterio de Educación y Ciencia | Ref. TIN2017-87604-

Photography-based taxonomy is inadequate, unnecessary, and potentially harmful for biological sciences

The question whether taxonomic descriptions naming new animal species without type specimen(s) deposited in collections should be accepted for publication by scientific journals and allowed by the Code has already been discussed in Zootaxa (Dubois & Nemésio 2007; Donegan 2008, 2009; Nemésio 2009a–b; Dubois 2009; Gentile & Snell 2009; Minelli 2009; Cianferoni & Bartolozzi 2016; Amorim et al. 2016). This question was again raised in a letter supported by 35 signatories published in the journal Nature (Pape et al. 2016) on 15 September 2016. On 25 September 2016, the following rebuttal (strictly limited to 300 words as per the editorial rules of Nature) was submitted to Nature, which on 18 October 2016 refused to publish it. As we think this problem is a very important one for zoological taxonomy, this text is published here exactly as submitted to Nature, followed by the list of the 493 taxonomists and collection-based researchers who signed it in the short time span from 20 September to 6 October 2016

Mortality and pulmonary complications in patients undergoing surgery with perioperative SARS-CoV-2 infection: an international cohort study

Background: The impact of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) on postoperative recovery needs to be understood to inform clinical decision making during and after the COVID-19 pandemic. This study reports 30-day mortality and pulmonary complication rates in patients with perioperative SARS-CoV-2 infection. Methods: This international, multicentre, cohort study at 235 hospitals in 24 countries included all patients undergoing surgery who had SARS-CoV-2 infection confirmed within 7 days before or 30 days after surgery. The primary outcome measure was 30-day postoperative mortality and was assessed in all enrolled patients. The main secondary outcome measure was pulmonary complications, defined as pneumonia, acute respiratory distress syndrome, or unexpected postoperative ventilation. Findings: This analysis includes 1128 patients who had surgery between Jan 1 and March 31, 2020, of whom 835 (74·0%) had emergency surgery and 280 (24·8%) had elective surgery. SARS-CoV-2 infection was confirmed preoperatively in 294 (26·1%) patients. 30-day mortality was 23·8% (268 of 1128). Pulmonary complications occurred in 577 (51·2%) of 1128 patients; 30-day mortality in these patients was 38·0% (219 of 577), accounting for 81·7% (219 of 268) of all deaths. In adjusted analyses, 30-day mortality was associated with male sex (odds ratio 1·75 [95% CI 1·28–2·40], p\textless0·0001), age 70 years or older versus younger than 70 years (2·30 [1·65–3·22], p\textless0·0001), American Society of Anesthesiologists grades 3–5 versus grades 1–2 (2·35 [1·57–3·53], p\textless0·0001), malignant versus benign or obstetric diagnosis (1·55 [1·01–2·39], p=0·046), emergency versus elective surgery (1·67 [1·06–2·63], p=0·026), and major versus minor surgery (1·52 [1·01–2·31], p=0·047). Interpretation: Postoperative pulmonary complications occur in half of patients with perioperative SARS-CoV-2 infection and are associated with high mortality. Thresholds for surgery during the COVID-19 pandemic should be higher than during normal practice, particularly in men aged 70 years and older. Consideration should be given for postponing non-urgent procedures and promoting non-operative treatment to delay or avoid the need for surgery. Funding: National Institute for Health Research (NIHR), Association of Coloproctology of Great Britain and Ireland, Bowel and Cancer Research, Bowel Disease Research Foundation, Association of Upper Gastrointestinal Surgeons, British Association of Surgical Oncology, British Gynaecological Cancer Society, European Society of Coloproctology, NIHR Academy, Sarcoma UK, Vascular Society for Great Britain and Ireland, and Yorkshire Cancer Research

A multi-country test of brief reappraisal interventions on emotions during the COVID-19 pandemic.

The COVID-19 pandemic has increased negative emotions and decreased positive emotions globally. Left unchecked, these emotional changes might have a wide array of adverse impacts. To reduce negative emotions and increase positive emotions, we tested the effectiveness of reappraisal, an emotion-regulation strategy that modifies how one thinks about a situation. Participants from 87 countries and regions (n = 21,644) were randomly assigned to one of two brief reappraisal interventions (reconstrual or repurposing) or one of two control conditions (active or passive). Results revealed that both reappraisal interventions (vesus both control conditions) consistently reduced negative emotions and increased positive emotions across different measures. Reconstrual and repurposing interventions had similar effects. Importantly, planned exploratory analyses indicated that reappraisal interventions did not reduce intentions to practice preventive health behaviours. The findings demonstrate the viability of creating scalable, low-cost interventions for use around the world

Mortality from gastrointestinal congenital anomalies at 264 hospitals in 74 low-income, middle-income, and high-income countries: a multicentre, international, prospective cohort study

Summary Background Congenital anomalies are the fifth leading cause of mortality in children younger than 5 years globally. Many gastrointestinal congenital anomalies are fatal without timely access to neonatal surgical care, but few studies have been done on these conditions in low-income and middle-income countries (LMICs). We compared outcomes of the seven most common gastrointestinal congenital anomalies in low-income, middle-income, and high-income countries globally, and identified factors associated with mortality. Methods We did a multicentre, international prospective cohort study of patients younger than 16 years, presenting to hospital for the first time with oesophageal atresia, congenital diaphragmatic hernia, intestinal atresia, gastroschisis, exomphalos, anorectal malformation, and Hirschsprung’s disease. Recruitment was of consecutive patients for a minimum of 1 month between October, 2018, and April, 2019. We collected data on patient demographics, clinical status, interventions, and outcomes using the REDCap platform. Patients were followed up for 30 days after primary intervention, or 30 days after admission if they did not receive an intervention. The primary outcome was all-cause, in-hospital mortality for all conditions combined and each condition individually, stratified by country income status. We did a complete case analysis. Findings We included 3849 patients with 3975 study conditions (560 with oesophageal atresia, 448 with congenital diaphragmatic hernia, 681 with intestinal atresia, 453 with gastroschisis, 325 with exomphalos, 991 with anorectal malformation, and 517 with Hirschsprung’s disease) from 264 hospitals (89 in high-income countries, 166 in middleincome countries, and nine in low-income countries) in 74 countries. Of the 3849 patients, 2231 (58·0%) were male. Median gestational age at birth was 38 weeks (IQR 36–39) and median bodyweight at presentation was 2·8 kg (2·3–3·3). Mortality among all patients was 37 (39·8%) of 93 in low-income countries, 583 (20·4%) of 2860 in middle-income countries, and 50 (5·6%) of 896 in high-income countries (p<0·0001 between all country income groups). Gastroschisis had the greatest difference in mortality between country income strata (nine [90·0%] of ten in lowincome countries, 97 [31·9%] of 304 in middle-income countries, and two [1·4%] of 139 in high-income countries; p≤0·0001 between all country income groups). Factors significantly associated with higher mortality for all patients combined included country income status (low-income vs high-income countries, risk ratio 2·78 [95% CI 1·88–4·11], p<0·0001; middle-income vs high-income countries, 2·11 [1·59–2·79], p<0·0001), sepsis at presentation (1·20 [1·04–1·40], p=0·016), higher American Society of Anesthesiologists (ASA) score at primary intervention (ASA 4–5 vs ASA 1–2, 1·82 [1·40–2·35], p<0·0001; ASA 3 vs ASA 1–2, 1·58, [1·30–1·92], p<0·0001]), surgical safety checklist not used (1·39 [1·02–1·90], p=0·035), and ventilation or parenteral nutrition unavailable when needed (ventilation 1·96, [1·41–2·71], p=0·0001; parenteral nutrition 1·35, [1·05–1·74], p=0·018). Administration of parenteral nutrition (0·61, [0·47–0·79], p=0·0002) and use of a peripherally inserted central catheter (0·65 [0·50–0·86], p=0·0024) or percutaneous central line (0·69 [0·48–1·00], p=0·049) were associated with lower mortality. Interpretation Unacceptable differences in mortality exist for gastrointestinal congenital anomalies between lowincome, middle-income, and high-income countries. Improving access to quality neonatal surgical care in LMICs will be vital to achieve Sustainable Development Goal 3.2 of ending preventable deaths in neonates and children younger than 5 years by 2030

Prevalence, associated factors and outcomes of pressure injuries in adult intensive care unit patients: the DecubICUs study

Funder: European Society of Intensive Care Medicine; doi: http://dx.doi.org/10.13039/501100013347Funder: Flemish Society for Critical Care NursesAbstract: Purpose: Intensive care unit (ICU) patients are particularly susceptible to developing pressure injuries. Epidemiologic data is however unavailable. We aimed to provide an international picture of the extent of pressure injuries and factors associated with ICU-acquired pressure injuries in adult ICU patients. Methods: International 1-day point-prevalence study; follow-up for outcome assessment until hospital discharge (maximum 12 weeks). Factors associated with ICU-acquired pressure injury and hospital mortality were assessed by generalised linear mixed-effects regression analysis. Results: Data from 13,254 patients in 1117 ICUs (90 countries) revealed 6747 pressure injuries; 3997 (59.2%) were ICU-acquired. Overall prevalence was 26.6% (95% confidence interval [CI] 25.9–27.3). ICU-acquired prevalence was 16.2% (95% CI 15.6–16.8). Sacrum (37%) and heels (19.5%) were most affected. Factors independently associated with ICU-acquired pressure injuries were older age, male sex, being underweight, emergency surgery, higher Simplified Acute Physiology Score II, Braden score 3 days, comorbidities (chronic obstructive pulmonary disease, immunodeficiency), organ support (renal replacement, mechanical ventilation on ICU admission), and being in a low or lower-middle income-economy. Gradually increasing associations with mortality were identified for increasing severity of pressure injury: stage I (odds ratio [OR] 1.5; 95% CI 1.2–1.8), stage II (OR 1.6; 95% CI 1.4–1.9), and stage III or worse (OR 2.8; 95% CI 2.3–3.3). Conclusion: Pressure injuries are common in adult ICU patients. ICU-acquired pressure injuries are associated with mainly intrinsic factors and mortality. Optimal care standards, increased awareness, appropriate resource allocation, and further research into optimal prevention are pivotal to tackle this important patient safety threat

Correction to: Prevalence, associated factors and outcomes of pressure injuries in adult intensive care unit patients: the DecubICUs study

The original version of this article unfortunately contained a mistake

Prevalence, associated factors and outcomes of pressure injuries in adult intensive care unit patients: the DecubICUs study

Funder: European Society of Intensive Care Medicine; doi: http://dx.doi.org/10.13039/501100013347Funder: Flemish Society for Critical Care NursesAbstract: Purpose: Intensive care unit (ICU) patients are particularly susceptible to developing pressure injuries. Epidemiologic data is however unavailable. We aimed to provide an international picture of the extent of pressure injuries and factors associated with ICU-acquired pressure injuries in adult ICU patients. Methods: International 1-day point-prevalence study; follow-up for outcome assessment until hospital discharge (maximum 12 weeks). Factors associated with ICU-acquired pressure injury and hospital mortality were assessed by generalised linear mixed-effects regression analysis. Results: Data from 13,254 patients in 1117 ICUs (90 countries) revealed 6747 pressure injuries; 3997 (59.2%) were ICU-acquired. Overall prevalence was 26.6% (95% confidence interval [CI] 25.9–27.3). ICU-acquired prevalence was 16.2% (95% CI 15.6–16.8). Sacrum (37%) and heels (19.5%) were most affected. Factors independently associated with ICU-acquired pressure injuries were older age, male sex, being underweight, emergency surgery, higher Simplified Acute Physiology Score II, Braden score 3 days, comorbidities (chronic obstructive pulmonary disease, immunodeficiency), organ support (renal replacement, mechanical ventilation on ICU admission), and being in a low or lower-middle income-economy. Gradually increasing associations with mortality were identified for increasing severity of pressure injury: stage I (odds ratio [OR] 1.5; 95% CI 1.2–1.8), stage II (OR 1.6; 95% CI 1.4–1.9), and stage III or worse (OR 2.8; 95% CI 2.3–3.3). Conclusion: Pressure injuries are common in adult ICU patients. ICU-acquired pressure injuries are associated with mainly intrinsic factors and mortality. Optimal care standards, increased awareness, appropriate resource allocation, and further research into optimal prevention are pivotal to tackle this important patient safety threat

Reducing the environmental impact of surgery on a global scale: systematic review and co-prioritization with healthcare workers in 132 countries

Abstract Background Healthcare cannot achieve net-zero carbon without addressing operating theatres. The aim of this study was to prioritize feasible interventions to reduce the environmental impact of operating theatres. Methods This study adopted a four-phase Delphi consensus co-prioritization methodology. In phase 1, a systematic review of published interventions and global consultation of perioperative healthcare professionals were used to longlist interventions. In phase 2, iterative thematic analysis consolidated comparable interventions into a shortlist. In phase 3, the shortlist was co-prioritized based on patient and clinician views on acceptability, feasibility, and safety. In phase 4, ranked lists of interventions were presented by their relevance to high-income countries and low–middle-income countries. Results In phase 1, 43 interventions were identified, which had low uptake in practice according to 3042 professionals globally. In phase 2, a shortlist of 15 intervention domains was generated. In phase 3, interventions were deemed acceptable for more than 90 per cent of patients except for reducing general anaesthesia (84 per cent) and re-sterilization of ‘single-use’ consumables (86 per cent). In phase 4, the top three shortlisted interventions for high-income countries were: introducing recycling; reducing use of anaesthetic gases; and appropriate clinical waste processing. In phase 4, the top three shortlisted interventions for low–middle-income countries were: introducing reusable surgical devices; reducing use of consumables; and reducing the use of general anaesthesia. Conclusion This is a step toward environmentally sustainable operating environments with actionable interventions applicable to both high– and low–middle–income countries

Improving communication services over mobile ad hoc networks in pedestrian and vehicular scenarios using virtualization

La idea de las redes ad-hoc (MANET) nace con el fin de proporcionar servicios de comunicaciones sin el soporte de infraestructura alguna. Típicamente, el estudio de este tipo de redes ha sido orientado a aplicaciones militares o a escenarios de desastres naturales donde la infraestructura es escasa, inexistente o no funcional. Sin embargo, en los últimos años, con el desarrollo de la tecnología inalámbrica, los investigadores han vislumbrado la oportunidad de prestar nuevos servicios de comunicación entre usuarios de electrónica de consumo. Así, los esfuerzos de la comunidad investigadora en este campo se han centrado en el diseño y evaluación de algoritmos y protocolos para implementar comunicaciones eficientes en escenarios donde los nodos móviles colaboran y comparten recursos para proveer funcionalidades usuales en las redes con infraestructura. En ese contexto, las redes móviles ad-hoc (MANETs) y las redes vehiculares adhoc (VANETs) han sido un tópico de extensa investigación por muchos años, con un sinnúmero de propuestas en la literatura para hacer frente a los desafíos planteados principalmente por la movilidad de los dispositivos. Muchos autores han defendido las MANETs como un elemento crucial para el futuro de los servicios de comunicación ubicuos. De igual forma, el desarrollo de las tecnologías de comunicaciones inalámbricas nos permite vislumbrar que en un futuro cercano las VANETs se convertirán en una extensión del Internet cableado, allanando el camino a un conjunto de nuevos servicios de comunicaciones. Esas visiones requieren medios para tornar este tipo de redes en ambientes de comunicación más robustos, capaces de soportar la operación de sistemas distribuidos que cursen grandes cantidades de información multimedia. Desde esta perspectiva, investigadores del Instituto Tecnológico de Massachusetts (MIT) propusieron una capa de virtualización, denominada Virtual Node Layer (VNLayer), con procedimientos para que nodos móviles físicos emulasen colaborativamente nodos virtuales que podrían ser direccionados como servidores en localizaciones conocidas. Esta aproximación se demostró conveniente para facilitar el desarrollo de software de aplicación en entornos tradicionales de MANETs. Esta tesis analiza las potencialidades de la virtualización para brindar nuevos servicios de comunicación en ambientes MANETs y VANETs, diseñando, desarrollando y evaluando nuevos mecanismos en la capa de virtualización para alcanzar este objetivo. Así, en primera instancia, presentamos un grupo de mejoras y nuevos mecanismos orientados a incrementar el rendimiento de la capa de virtualización en entornos MANETs de mayor movilidad y con aplicaciones más demandantes, otorgándole flexibilidad para ajustarse a las necesidades de los usuarios, y una mayor robustez y rapidez para reaccionar ante los fallos provocados por la movilidad de los nodos o las condiciones adversas del medio inalámbrico (pérdida de paquetes de control debido a colisiones, ruido, etc.). De igual forma, proponemos una serie de mejoras a la versión virtualizada del protocolo de encaminamiento AODV para aprovechar las nuevas características de la capa de virtualización, así como nuevos procedimientos para evitar la pérdida de paquetes debido a la movilidad de los nodos físicos que le dan soporte. Ya en el campo de las VANETs, este trabajo introduce por primera vez el concepto de la capa de virtualización en estos ambientes. Para ello, hemos diseñado varios procesos que permiten (i) adaptar la forma y ubicación de las regiones cubiertas por los nodos virtuales a las condiciones de los planos de las calles y vías, propias del entorno urbano, y (ii) ofrecer una reacción más rápida y robusta de los nodos virtuales frente la alta variabilidad y movilidad de los vehículos y las condiciones de mayor pérdida de paquetes de las redes vehiculares. Adicionalmente, diseñamos un nuevo protocolo de encaminamiento que aprovecha las ventajas ofrecidas por la capa de virtualización en los entornos vehiculares para obtener un mejor rendimiento que algunos protocolos presentes en la literatura. Nuestras contribuciones a la capa de virtualización, tanto en el campo de las MANETs como en el de las VANETs, son validadas a través de una serie de experimentos de simulación, desarrollados en diferentes escenarios y aplicaciones, y contrastadas con varios protocolos relevantes en la literatura. Los resultados muestran que los nuevos mecanismos que hemos implementado superan notablemente el rendimiento de la VNLayer original, al tiempo que aseguran mejores prestaciones en las comunicaciones que varios algoritmos relevantes en el campo de los escenarios propuestos, asegurando una buena tasa de entrega de paquetes gracias a la efectiva explotación de las comunicaciones multisalto.Ad-hoc networks arose with the aim of providing communication services without the support of any fixed infrastructure. Typically, the study of these kind of networks has been focused on military applications or natural disaster scenarios where infrastructure is scarce, nonexistent or nonfunctional. However, in recent years, with the development of wireless technology, researchers have envisioned the opportunity to provide new communication services among users of consumer electronics. Thus, the efforts of the research community in this field have focused on the design and evaluation of algorithms and protocols to implement efficient communications in scenarios where mobile nodes collaborate and share resources to provide functionalities which are common in networks with infrastructure. In this context, mobile ad-hoc networks (MANETs) and vehicular ad-hoc networks (VANETs) have been a topic of extensive research for many years, with countless proposals in the literature dealing with the challenges raised mainly by the mobility of devices. Many authors have defended MANETs as a crucial element for the future of pervasive communication services. Similarly, the development of wireless communication technologies allows us to foresee that VANETs will become an extension of the wired Internet in the near future, paving the way to a set of new communication services. These visions require means to turn this kind of networks into more robust communication environments, capable of supporting the operation of distributed systems carrying large amounts of multimedia information. From this perspective, researchers from the Massachusetts Institute Technology (MIT) presented a layer of virtualization, called the Virtual Node Layer (VNLayer), with procedures for physical mobile nodes to collaboratively emulate virtual nodes that could be addressed as server devices in known locations. This approach has proven suitable for easy development of application software in traditional MANET environments. In this thesis we are interested in analyzing the potential of the virtualization to provide new communication services in MANET and VANET environments, designing, developing and testing new mechanisms within the virtualization layer to achieve this goal. So, firstly, we present a set of improvements and new mechanisms aimed at increasing the performance of the virtualization layer in MANET environments with higher mobility and more demanding applications, giving it flexibility to adapt to the needs of users, and greater robustness and speed to react to failures caused by the mobility of nodes or adverse conditions of the wireless medium (control packet loss due to collisions, noise, etc.). Likewise, we propose a set of enhancements to the virtualized version of the routing protocol AODV to exploit new features of the virtualization layer, as well as new procedures to avoid packet losses due to the mobility of physical nodes that support it. To the best of our knowledge, this thesis is the first study to introduce the concept of virtualization layer in VANET environments. To do this, we designed several processes that allow (i) adapt the shape and location of the regions covered by the virtual nodes to the conditions of the layouts of the streets and roads, typical of urban environment, and (ii) provide a faster and more robust response of the virtual nodes to deal to high variability and mobility of vehicles, and the major conditions for packet loss in vehicular networks. Additionally, we design a new routing protocol that takes advantage of the virtualization layer to deliver better performance than recent protocols in the literature. Our contributions to the virtualization layer, both in the field of MANETs as in VANETs, are validated through a set of simulation experiments, developed in different scenarios and applications, and compared with several relevant protocols representative of the current state-of-the-art. The results of simulation experiments conducted in MANET and VANET environments show that the new mechanisms we have implemented significantly outperformthe original VNLayer, while ensuring best performance in communications that the most relevant algorithms in the field of the proposed scenarios. A good packet delivery rate is assured thanks to the effective operation of multi-hop communications