Geografische Empfehlungssysteme

Mobile Geräte werden immer häufiger mit Sensoren zur Bestimmung der eigenen Position ausgestattet, zum Beispiel mit GPS. Mit Hilfe der Ortsinformationen dieser Sensoren können beispielsweise moderne Bildmanagementanwendungen digitale Fotos automatisch nach geografischen Regionen gruppieren oder passende Schlagworte generieren. Dies führt unter anderem zu einer besseren Suchbarkeit dieser digitalen Daten. Grundsätzlich geben Ortsinformationen in digitalen Fotos nicht nur Hinweise auf das Foto selbst, sondern machen auch sichtbar, welche geografischen Entscheidungen der Fotograf bei deren Erstellung getroffen hat. Diese Arbeit nutzt diese Entscheidungen für die Berechnung von weiteren Empfehlungen für den Nutzer, beispielsweise einer Bildmanagementanwendung. Ein konkreter Anwendungsfall lautet folgendermaßen: Einem Nutzer sollen für eine frei wählbare geographische Region (z.B. einer Stadt), mehrere Bilder empfohlen werden, die zum einen typisch für diese Region sind, zum anderen aber auch für ihn persönlich interessant sein könnten. Um diese geografischen Mehr-Objekt-Empfehlungen zu berechnen, wurde ein neuartiger Algorithmus entwickelt, der zunächst die Ortsinformationen aller Nutzer zu einem geografischen Modell bündelt. Auf Grundlage dieser prototypischen Konzeptualisierung von einzelnen Regionen, können dann typische Bilder empfohlen werden. Weiterhin werden diese geografischen Modelle in einem zweiten Schritt für die zusätzliche Gewichtung der einzelnen geografischen Entscheidungen der Nutzer verwendet, um über den Ansatz eines kollaborativen Filters zu einer persönlichen Empfehlung zu gelangen. Dazu wurden mehrere Verfahren entwickelt und miteinander verglichen. Diese Arbeit ist im Rahmen des europäischen Projektes Tripod entstanden, für das der entwickelte geografische Empfehlungsalgorithmus als Softwaremodul prototypisch implementiert wurde. Damit wurden die Empfehlungen mit Hilfe von georeferenzierten Bildern evaluiert, die auf den Online-Galerien Panoramio.com und Flickr.de veröffentlicht wurden. Durch die Auswertung der geografischen Informationen und der daraus berechneten Ortsmodelle, ließen sich deutlich präzisere Empfehlungen vorschlagen, als mit anderen bekannten Empfehlungsverfahren

Antibodies to squalene in US Navy Persian Gulf War veterans with chronic multisymptom illness. Vaccine

a b s t r a c t Since the end of the 1991 Gulf War, there have been reports of unexplained, multisymptom illnesses afflicting veterans who consistently report more symptoms than do nondeployed veterans. One of the many possible exposures suspected of causing chronic multisymptom illnesses Gulf War veterans is squalene, thought to be present in anthrax vaccine. We examined the relationship between squalene antibodies and chronic symptoms reported by Navy construction workers (Seabees), n = 579. 30.2% were deployers, 7.4% were defined as ill, and 43.5% were positive for squalene antibodies. We found no association between squalene antibody status and chronic multisymptom illness (p = 0.465). The etiology of Gulf War syndrome remains unknown, but should not include squalene antibody status. Published by Elsevier Ltd

Structural and functional basis of mammalian microRNA biogenesis by Dicer

MicroRNA (miRNA) and RNA interference (RNAi) pathways rely on small RNAs produced by Dicer endonucleases. Mammalian Dicer primarily supports the essential gene-regulating miRNA pathway, but how it is specifically adapted to miRNA biogenesis is unknown. We show that the adaptation entails a unique structural role of Dicer’s DExD/H helicase domain. Although mice tolerate loss of its putative ATPase function, the complete absence of the domain is lethal because it assures high-fidelity miRNA biogenesis. Structures of murine Dicer⋅miRNA precursor complexes revealed that the DExD/H domain has a helicase-unrelated structural function. It locks Dicer in a closed state, which facilitates miRNA precursor selection. Transition to a cleavage-competent open state is stimulated by Dicer-binding protein TARBP2. Absence of the DExD/H domain or its mutations unlocks the closed state, reduces substrate selectivity, and activates RNAi. Thus, the DExD/H domain structurally contributes to mammalian miRNA biogenesis and underlies mechanistical partitioning of miRNA and RNAi pathways

Outcome in patients perceived as receiving excessive care across different ethical climates: a prospective study in 68 intensive care units in Europe and the USA

Purpose: Whether the quality of the ethical climate in the intensive care unit (ICU) improves the identification of patients receiving excessive care and affects patient outcomes is unknown. Methods: In this prospective observational study, perceptions of excessive care (PECs) by clinicians working in 68 ICUs in Europe and the USA were collected daily during a 28-day period. The quality of the ethical climate in the ICUs was assessed via a validated questionnaire. We compared the combined endpoint (death, not at home or poor quality of life at 1 year) of patients with PECs and the time from PECs until written treatment-limitation decisions (TLDs) and death across the four climates defined via cluster analysis. Results: Of the 4747 eligible clinicians, 2992 (63%) evaluated the ethical climate in their ICU. Of the 321 and 623 patients not admitted for monitoring only in ICUs with a good (n = 12, 18%) and poor (n = 24, 35%) climate, 36 (11%) and 74 (12%), respectively were identified with PECs by at least two clinicians. Of the 35 and 71 identified patients with an available combined endpoint, 100% (95% CI 90.0–1.00) and 85.9% (75.4–92.0) (P = 0.02) attained that endpoint. The risk of death (HR 1.88, 95% CI 1.20–2.92) or receiving a written TLD (HR 2.32, CI 1.11–4.85) in patients with PECs by at least two clinicians was higher in ICUs with a good climate than in those with a poor one. The differences between ICUs with an average climate, with (n = 12, 18%) or without (n = 20, 29%) nursing involvement at the end of life, and ICUs with a poor climate were less obvious but still in favour of the former. Conclusion: Enhancing the quality of the ethical climate in the ICU may improve both the identification of patients receiving excessive care and the decision-making process at the end of life

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

Rationale, Design and Baseline Characteristics of Participants in the Cardiovascular Outcomes for People Using Anticoagulation Strategies (COMPASS) Trial

Long-term aspirin prevents vascular events but is only modestly effective. Rivaroxaban alone or in combination with aspirin might be more effective than aspirin alone for vascular prevention in patients with stable coronary artery disease (CAD) or peripheral artery disease (PAD). Rivaroxaban as well as aspirin increase upper gastrointestinal (GI) bleeding and this might be prevented by proton pump inhibitor therapy. Cardiovascular Outcomes for People Using Anticoagulation Strategies (COMPASS) is a double-blind superiority trial comparing rivaroxaban 2.5 mg twice daily combined with aspirin 100 mg once daily or rivaroxaban 5 mg twice daily vs aspirin 100 mg once daily for prevention of myocardial infarction, stroke, or cardiovascular death in patients with stable CAD or PAD. Patients not taking a proton pump inhibitor were also randomized, using a partial factorial design, to pantoprazole 40 mg once daily or placebo. The trial was designed to have at least 90% power to detect a 20% reduction in each of the rivaroxaban treatment arms compared with aspirin and to detect a 50% reduction in upper GI complications with pantoprazole compared with placebo. Between February 2013 and May 2016, we recruited 27,395 participants from 602 centres in 33 countries; 17,598 participants were included in the pantoprazole vs placebo comparison. At baseline, the mean age was 68.2 years, 22.0% were female, 90.6% had CAD, and 27.3% had PAD. COMPASS will provide information on the efficacy and safety of rivaroxaban, alone or in combination with aspirin, in the long-term management of patients with stable CAD or PAD, and on the efficacy and safety of pantoprazole in preventing upper GI complications in patients receiving antithrombotic therapy

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

Photographing a city: an analysis of place concepts based on spatial choices

We ask whether the photographs published in web-based image collections do represent different conceptualizations of a city. We present a method for gathering and analyzing a data set of more than 12.000 images from Amsterdam, Bamberg, Cardiff, and Dublin. A measure for the popularity of a location in a city is described. The analysis of the data set reveals that the popularity follows a power law with very few highly popular locations and a long tail of places in a city that are visited only occasionally. The most popular locations can be identified with the semantic core of the conceptualization of the city in terms of images. This raises the issue of individual differences. We propose another measure that permits to identify users with similar conceptualizations of a city. Subject areas: Geospatial semantics