Automatic registration with continuous pose updates for marker-less surgical navigation in spine surgery

Established surgical navigation systems for pedicle screw placement have been proven to be accurate, but still reveal limitations in registration or surgical guidance. Registration of preoperative data to the intraoperative anatomy remains a time-consuming, error-prone task that includes exposure to harmful radiation. Surgical guidance through conventional displays has well-known drawbacks, as information cannot be presented in-situ and from the surgeon's perspective. Consequently, radiation-free and more automatic registration methods with subsequent surgeon-centric navigation feedback are desirable. In this work, we present a marker-less approach that automatically solves the registration problem for lumbar spinal fusion surgery in a radiation-free manner. A deep neural network was trained to segment the lumbar spine and simultaneously predict its orientation, yielding an initial pose for preoperative models, which then is refined for each vertebra individually and updated in real-time with GPU acceleration while handling surgeon occlusions. An intuitive surgical guidance is provided thanks to the integration into an augmented reality based navigation system. The registration method was verified on a public dataset with a median of 100% successful registrations, a median target registration error of 2.7 mm, a median screw trajectory error of 1.6°and a median screw entry point error of 2.3 mm. Additionally, the whole pipeline was validated in an ex-vivo surgery, yielding a 100% screw accuracy and a median target registration error of 1.0 mm. Our results meet clinical demands and emphasize the potential of RGB-D data for fully automatic registration approaches in combination with augmented reality guidance

Human behaviour in emergency situations: comparisons between aviation and rail domains

This article presents a comparative review of the knowledge base regarding human behaviour in emergencies for both aviation and rail domains. Generic models of human behaviour in emergency situations are introduced and specific attention is then focussed on methods of behaviour prediction, exhibited behaviours in emergencies and methods of aiding evacuation across both modes of transport. Using established knowledge from the aviation domain, it has been possible to make observations and comparisons about the rail domain. Traditionally, the aviation domain has been a major focus of research attention and this is used to inform and interpret the rail domain. By drawing comparisons across these domains for human behaviour in emergency situations, the observations are discussed along with recommendations for future policies/planning for emergencies and future research areas

Antimicrobial resistance among migrants in Europe: a systematic review and meta-analysis

BACKGROUND: Rates of antimicrobial resistance (AMR) are rising globally and there is concern that increased migration is contributing to the burden of antibiotic resistance in Europe. However, the effect of migration on the burden of AMR in Europe has not yet been comprehensively examined. Therefore, we did a systematic review and meta-analysis to identify and synthesise data for AMR carriage or infection in migrants to Europe to examine differences in patterns of AMR across migrant groups and in different settings. METHODS: For this systematic review and meta-analysis, we searched MEDLINE, Embase, PubMed, and Scopus with no language restrictions from Jan 1, 2000, to Jan 18, 2017, for primary data from observational studies reporting antibacterial resistance in common bacterial pathogens among migrants to 21 European Union-15 and European Economic Area countries. To be eligible for inclusion, studies had to report data on carriage or infection with laboratory-confirmed antibiotic-resistant organisms in migrant populations. We extracted data from eligible studies and assessed quality using piloted, standardised forms. We did not examine drug resistance in tuberculosis and excluded articles solely reporting on this parameter. We also excluded articles in which migrant status was determined by ethnicity, country of birth of participants' parents, or was not defined, and articles in which data were not disaggregated by migrant status. Outcomes were carriage of or infection with antibiotic-resistant organisms. We used random-effects models to calculate the pooled prevalence of each outcome. The study protocol is registered with PROSPERO, number CRD42016043681. FINDINGS: We identified 2274 articles, of which 23 observational studies reporting on antibiotic resistance in 2319 migrants were included. The pooled prevalence of any AMR carriage or AMR infection in migrants was 25·4% (95% CI 19·1-31·8; I2 =98%), including meticillin-resistant Staphylococcus aureus (7·8%, 4·8-10·7; I2 =92%) and antibiotic-resistant Gram-negative bacteria (27·2%, 17·6-36·8; I2 =94%). The pooled prevalence of any AMR carriage or infection was higher in refugees and asylum seekers (33·0%, 18·3-47·6; I2 =98%) than in other migrant groups (6·6%, 1·8-11·3; I2 =92%). The pooled prevalence of antibiotic-resistant organisms was slightly higher in high-migrant community settings (33·1%, 11·1-55·1; I2 =96%) than in migrants in hospitals (24·3%, 16·1-32·6; I2 =98%). We did not find evidence of high rates of transmission of AMR from migrant to host populations. INTERPRETATION: Migrants are exposed to conditions favouring the emergence of drug resistance during transit and in host countries in Europe. Increased antibiotic resistance among refugees and asylum seekers and in high-migrant community settings (such as refugee camps and detention facilities) highlights the need for improved living conditions, access to health care, and initiatives to facilitate detection of and appropriate high-quality treatment for antibiotic-resistant infections during transit and in host countries. Protocols for the prevention and control of infection and for antibiotic surveillance need to be integrated in all aspects of health care, which should be accessible for all migrant groups, and should target determinants of AMR before, during, and after migration. FUNDING: UK National Institute for Health Research Imperial Biomedical Research Centre, Imperial College Healthcare Charity, the Wellcome Trust, and UK National Institute for Health Research Health Protection Research Unit in Healthcare-associated Infections and Antimictobial Resistance at Imperial College London

Country Concepts and the Rational Actor Trap: Limitations to Strategic Management of International NGOs

Growing criticism of inefficient development aid demanded new planning instruments of donors, including international NGOs (INGOs). A reorientation from isolated project-planning towards holistic country concepts and the increasing rationality of a result-orientated planning process were seen as answer. However, whether these country concepts - newly introduced by major INGOs too - have increased the efficiency of development cooperation is open to question. Firstly, there have been counteracting external factors, like the globalization of the aid business, that demanded structural changes in the composition of INGO portfolios towards growing short-term humanitarian aid; this was hardly compatible with the requirements of medium-term country planning. Secondly, the underlying vision of rationality as a remedy for the major ills of development aid was in itself a fallacy. A major change in the methodology of planning, closely connected with a shift of emphasis in the approach to development cooperation, away from project planning and service delivery, towards supporting the socio-cultural and political environment of the recipient communities, demands a reorientation of aid management: The most urgent change needed is by donors, away from the blinkers of result-orientated planning towards participative organizational cultures of learning.Des critiques croissantes de l'aide au développement inefficace exigent de nouveaux instruments de planification des bailleurs de fonds, y compris les ONG internationales (ONGI). Une réorientation de la planification des projets isolés vers des concepts holistiques de la planification de l’aide par pays ainsi que la rationalité croissante d'un processus de planification orientée vers les résultats ont été considérés comme réponse. Toutefois, si ces concepts de pays - nouvellement introduites par les grandes OING eux aussi - ont augmenté l'efficacité de la coopération au développement est ouvert à la question. Tout d'abord, il y a eu l’impact des facteurs externes, comme la mondialisation de l'entreprise de l'aide, qui a exigé des changements structurels dans la composition des portefeuilles des OING vers la croissance de l'aide humanitaire à court terme. Cela était difficilement compatible avec les exigences de l'aménagement du territoire à moyen terme. Deuxièmement, la vision sous-jacente de la rationalité accrue de la planification, concentré sur les resultats, comme un remède pour les grands maux de l'aide au développement était en soi une erreur. Un changement majeur dans la méthodologie de la planification, étroitement liée à un changement d'orientation dans l'approche de la coopération au développement, qui n’est pas concentrer sur planification du projet et la prestation de services, mais qui soutienne l'environnement socio-culturel et politique des communautés bénéficiaires, exige une réorientation de la gestion de l’aide: Le changement le plus urgent est un changement par les donateurs eux-mêmes, qui devrait implanter des cultures de collaboration étroit avec les partenaires et la population locale

Creative destruction in science

Drawing on the concept of a gale of creative destruction in a capitalistic economy, we argue that initiatives to assess the robustness of findings in the organizational literature should aim to simultaneously test competing ideas operating in the same theoretical space. In other words, replication efforts should seek not just to support or question the original findings, but also to replace them with revised, stronger theories with greater explanatory power. Achieving this will typically require adding new measures, conditions, and subject populations to research designs, in order to carry out conceptual tests of multiple theories in addition to directly replicating the original findings. To illustrate the value of the creative destruction approach for theory pruning in organizational scholarship, we describe recent replication initiatives re-examining culture and work morality, working parents\u2019 reasoning about day care options, and gender discrimination in hiring decisions. Significance statement It is becoming increasingly clear that many, if not most, published research findings across scientific fields are not readily replicable when the same method is repeated. Although extremely valuable, failed replications risk leaving a theoretical void\u2014 reducing confidence the original theoretical prediction is true, but not replacing it with positive evidence in favor of an alternative theory. We introduce the creative destruction approach to replication, which combines theory pruning methods from the field of management with emerging best practices from the open science movement, with the aim of making replications as generative as possible. In effect, we advocate for a Replication 2.0 movement in which the goal shifts from checking on the reliability of past findings to actively engaging in competitive theory testing and theory building. Scientific transparency statement The materials, code, and data for this article are posted publicly on the Open Science Framework, with links provided in the article

Surgical site infection after gastrointestinal surgery in high-income, middle-income, and low-income countries: a prospective, international, multicentre cohort study

Background: Surgical site infection (SSI) is one of the most common infections associated with health care, but its importance as a global health priority is not fully understood. We quantified the burden of SSI after gastrointestinal surgery in countries in all parts of the world. Methods: This international, prospective, multicentre cohort study included consecutive patients undergoing elective or emergency gastrointestinal resection within 2-week time periods at any health-care facility in any country. Countries with participating centres were stratified into high-income, middle-income, and low-income groups according to the UN's Human Development Index (HDI). Data variables from the GlobalSurg 1 study and other studies that have been found to affect the likelihood of SSI were entered into risk adjustment models. The primary outcome measure was the 30-day SSI incidence (defined by US Centers for Disease Control and Prevention criteria for superficial and deep incisional SSI). Relationships with explanatory variables were examined using Bayesian multilevel logistic regression models. This trial is registered with ClinicalTrials.gov, number NCT02662231. Findings: Between Jan 4, 2016, and July 31, 2016, 13 265 records were submitted for analysis. 12 539 patients from 343 hospitals in 66 countries were included. 7339 (58·5%) patient were from high-HDI countries (193 hospitals in 30 countries), 3918 (31·2%) patients were from middle-HDI countries (82 hospitals in 18 countries), and 1282 (10·2%) patients were from low-HDI countries (68 hospitals in 18 countries). In total, 1538 (12·3%) patients had SSI within 30 days of surgery. The incidence of SSI varied between countries with high (691 [9·4%] of 7339 patients), middle (549 [14·0%] of 3918 patients), and low (298 [23·2%] of 1282) HDI (p < 0·001). The highest SSI incidence in each HDI group was after dirty surgery (102 [17·8%] of 574 patients in high-HDI countries; 74 [31·4%] of 236 patients in middle-HDI countries; 72 [39·8%] of 181 patients in low-HDI countries). Following risk factor adjustment, patients in low-HDI countries were at greatest risk of SSI (adjusted odds ratio 1·60, 95% credible interval 1·05–2·37; p=0·030). 132 (21·6%) of 610 patients with an SSI and a microbiology culture result had an infection that was resistant to the prophylactic antibiotic used. Resistant infections were detected in 49 (16·6%) of 295 patients in high-HDI countries, in 37 (19·8%) of 187 patients in middle-HDI countries, and in 46 (35·9%) of 128 patients in low-HDI countries (p < 0·001). Interpretation: Countries with a low HDI carry a disproportionately greater burden of SSI than countries with a middle or high HDI and might have higher rates of antibiotic resistance. In view of WHO recommendations on SSI prevention that highlight the absence of high-quality interventional research, urgent, pragmatic, randomised trials based in LMICs are needed to assess measures aiming to reduce this preventable complication

Robust estimation of bacterial cell count from optical density

Optical density (OD) is widely used to estimate the density of cells in liquid culture, but cannot be compared between instruments without a standardized calibration protocol and is challenging to relate to actual cell count. We address this with an interlaboratory study comparing three simple, low-cost, and highly accessible OD calibration protocols across 244 laboratories, applied to eight strains of constitutive GFP-expressing E. coli. Based on our results, we recommend calibrating OD to estimated cell count using serial dilution of silica microspheres, which produces highly precise calibration (95.5% of residuals &lt;1.2-fold), is easily assessed for quality control, also assesses instrument effective linear range, and can be combined with fluorescence calibration to obtain units of Molecules of Equivalent Fluorescein (MEFL) per cell, allowing direct comparison and data fusion with flow cytometry measurements: in our study, fluorescence per cell measurements showed only a 1.07-fold mean difference between plate reader and flow cytometry data

Cachimbos europeus de cerâmica branca, séculos XVI ao XIX: parâmetros básicos para análise arqueológica

O tabaco foi introduzido na Europa no final do século XV. Desde então, uma das formas mais comuns para o seu consumo foi o cachimbo, além do rapé, do tabaco de mascar, do charuto e, mais recentemente, dos cigarros. Os cachimbos de cerâmica branca, largamente produzidos e utilizados na Europa desde o século XV, são encontrados em sítios arqueológicos históricos ao redor do mundo, incluindo no Brasil, em decorrência do comércio internacional, que gradualmente se intensificou após o início da conquista europeia. Eles funcionam como excelentes elementos para datação de sítios e estratos arqueológicos, tendo sido estudados em vários países a partir dessa abordagem. Ainda, esse tipo de artefato, mais que fornecer datações, permite identificar redes comerciais entre nações e desenvolver discussões de cunho social e cultural. Contudo, eles foram pouco estudados no Brasil. Visando contribuir com os estudos nacionais dessa categoria material, este artigo oferece uma revisão da literatura internacional acerca do histórico da produção dos cachimbos europeus de caulim, incluindo apresentação dos principais centros produtores; da morfologia e decoração desses produtos, considerando a cronologia do fabrico; e dos métodos de análise dos diferentes cachimbos de caulim no âmbito da arqueologia histórica.Tobacco was introduced in Europe at the end of the 15th century. Since then, one of the most traditional means for its use has been the pipe, next to the powder version, chewing, cigars, and, more recently, cigarettes. White clay tobacco pipes, widely produced and used in Europe since the 15th century, are found in historical archaeological sites around the world, including Brazil, due to international trade, which gradually intensified with the European conquest of the New World. They are excellent guides for dating archaeological sites and layers. In addition, this type of artifact, more than a dating tool, permits identifying trading networks between nations and developing discussions of cultural and social nature. These pipes, however, have been understudied in Brazil. In order to contribute to studies of this type of artifact in our country, this paper offers a revision of the international literature on the history of clay pipe production in Europe, including the presentation of main production centers; morphology and decoration of these products, considering issues of fabrication chronology; and the methods used in Historical Archaeology for analyzing clay tobacco pipes