The intellectual might and the creative and innovative spirit of the faculty and students at our research universities play a key role in providing the basis for many inventions and innovations that ...address pressing problems of today’s society. Many universities have built the vibrant culture and the nurturing environment that supports academic innovation and entrepreneurship and they have developed mechanisms that encourage and incentivize the translation of research breakthroughs into new products and processes. Urban environments, particularly big cities, face unprecedented challenges to address the needs of its citizens as more and more people move from rural parts of the world to cities in search of a better life and more economic opportunities. Securing reliable transportation of people and goods, adequate electrical power and water to satisfy the needs of the growing urban population, addressing the ever increasing waste disposal needs, maintaining the health and wellness of the general population, but especially of older adults and people with disabilities require a new paradigm for urban science, engineering, and innovation. Many universities have responded to this challenge and have developed research pillars around the challenges and opportunities that complex urban systems pose.
Are coagulase-negative staphylococci virulent? Heilmann, C.; Ziebuhr, W.; Becker, K.
Clinical microbiology and infection,
September 2019, 2019-Sep, 2019-09-00, 20190901, Volume:
25, Issue:
9
Journal Article
Peer reviewed
Open access
Progress in contemporary medicine is associated with an increasing number of immunocompromised individuals. In this vulnerable group, the underlying disease together with long-term hospitalization ...and the use of medical devices facilitate infections by opportunistic pathogens, of which coagulase-negative staphylococci (CoNS) represent a prime example.
The diversity of CoNS with species- and strain-specific differences concerning virulence and clinical impact is highlighted. A focus is on the ability of CoNS to generate biofilms on biotic and abiotic surfaces, which enables skin and mucosa colonization as well as establishment of CoNS on indwelling foreign bodies.
Literature about the virulence of CoNS listed in PubMed was reviewed.
Most catheter-related and prosthetic joint infections as well as most other device-related infections are caused by CoNS, specifically by Staphylococcus epidermidis and Staphylococcus haemolyticus. A common theme of CoNS infections is a high antibiotic resistance rate, which often limits treatment options and contributes to the significant health and economic burden imposed by CoNS.
Breaching the skin barrier along with the insertion of medical devices offers CoNS opportunities to gain access to host tissues and to sustain there by forming biofilms on foreign body surfaces. Biofilms represent the perfect niche to protect CoNS from both the host immune response and the action of antibiotics. Their particular lifestyle, combined with conditions that facilitate host colonization and infection, has led to the growing impact of CoNS as pathogens. Moreover, CoNS may serve as hidden reservoirs for antibiotic resistance and virulence traits.
The field of astroparticle physics is currently developing rapidly, since new experiments challenge our understanding of processes that have been investigated. Three messengers can be used to extract ...information on the properties of astrophysical sources: photons, charged Cosmic Rays and neutrinos. This review focuses on high-energy neutrinos (
E
ν
>
100
GeV
) with the main topics as follows.
•
The production mechanism of high-energy neutrinos in astrophysical shocks. The connection between the observed photon spectra and charged Cosmic Rays is described and the source properties as they are known from photon observations and from charged Cosmic Rays are presented.
•
High-energy neutrino detection. Current detection methods are described and the status of the next generation neutrino telescopes are reviewed. In particular, water and ice Cherenkov detectors as well as radio measurements in ice and with balloon experiments are presented. In addition, future perspectives for optical, radio and acoustic detection of neutrinos are reviewed.
•
Sources of neutrino emission. The main source classes are reviewed, i.e. galactic sources, Active Galactic Nuclei, starburst galaxies and Gamma Ray Bursts. The interaction of high energy protons with the cosmic microwave background implies the production of neutrinos, referred to as GZK neutrinos.
•
Implications of neutrino flux limits. Recent limits given by the AMANDA experiment and their implications regarding the physics of the sources are presented.
Objectives
To review the scientific literature pertaining to the use of hand‐carried and hand‐held ultrasound devices in low‐ and middle‐income countries (LMIC), with a focus on clinical ...applications, geographical areas of use, the impact on patient management and technical features of the devices used.
Methods
The electronic databases PubMed and Google Scholar were searched. No language or date restrictions were applied. Case reports and original research describing the use of hand‐carried ultrasound devices in LMIC were included if agreed upon as relevant by two‐reviewer consensus based on our predefined research questions.
Results
A total of 644 articles were found and screened, and 36 manuscripts were included for final review. Twenty‐seven studies were original research articles, and nine were case reports. Several reports describe the successful diagnosis and management of difficult, often life‐threatening conditions, using hand‐carried and hand‐held ultrasound. These portable ultrasound devices have also been studied for cardiac screening exams, as well as a rapid triage tool in rural areas and after natural disaster. Most applications focus on obstetrical and abdominal complaints. Portable ultrasound may have an impact on clinical management in up to 70% of all cases. However, no randomised controlled trials have evaluated the impact of ultrasound‐guided diagnosis and treatment in resource‐constrained settings. The exclusion of articles published in journals not listed in the large databases may have biased our results. Our findings are limited by the lack of higher quality evidence (e.g. controlled trials).
Conclusions
Hand‐carried and hand‐held ultrasound is successfully being used to triage, diagnose and treat patients with a variety of complaints in LMIC. However, the quality of the current evidence is low. There is an urgent need to perform larger clinical trials assessing the impact of hand‐carried ultrasound in LMIC.
Objectifs
Passer en revue la littérature scientifique portant sur l'utilisation d'appareils d’échographie portatifs dans les pays à faible revenu et à revenu intermédiaire (PFR‐PRI) en mettant l'accent sur les applications cliniques, les zones géographiques d'utilisation, l'impact sur la prise en charge des patients et les caractéristiques techniques des appareils utilisés.
Méthodes
Recherche effectuée dans les bases de données électroniques PubMed et Google Scholar. Aucune restriction linguistique ou de période n'a été appliquée. Les rapports de cas et les recherches originales décrivant l'utilisation d'appareils d’échographie portatifs dans les PFR‐PRI ont été inclus, si trouvés pertinents par le consensus de deux reviewers, basé sur nos questions de recherche prédéfinies.
Résultats
644 articles ont été trouvés et analysés, 36 manuscrits ont été inclus pour analyse finale. 27 études faisaient l'objet d'articles de recherche originale et 9 étaient des rapports de cas. Plusieurs rapports décrivent le diagnostic et la prise en charge avec succès de conditions difficiles, souvent mortelles, en utilisant des appareils d’échographie portatifs. Ces dispositifs d’échographie portatifs ont également été étudiés pour les examens de dépistage cardiaques, ainsi que comme outil de triage rapide dans les zones rurales et à la suite de catastrophes naturelles. La plupart des applications se concentrent sur les plaintes obstétricales et abdominales. L’échographie portative peut avoir un impact sur la prise en charge clinique dans 70% de tous les cas. Cependant, aucun essai contrôlé randomisé n'a évalué l'impact sur le diagnostic et le traitement guidé par l’échographie dans les milieux à ressources limitées. L'exclusion des articles publiés dans des revues ne figurant pas dans les grandes bases de données peut avoir biaisé nos résultats. Nos résultats sont limités par le manque de donnée de meilleure qualité (par ex., les essais contrôlés).
Conclusions
L’échographie portative et réalisée à la main est utilisée avec succès au triage, au diagnostic et pour le traitement des patients avec diverses plaintes dans PFR‐PRI. Cependant, la qualité des données actuelles est faible. Il est urgent de procéder à des essais cliniques de grande envergure évaluant l'impact de l’échographie réalisée à la main dans les PFR‐PRI.
Objetivos
Revisar la literatura científica existente sobre el uso de aparatos portátiles de ultrasonido en países con ingresos bajos y medios (PIBM), con especial atención en las aplicaciones clínicas, las áreas geográficas de uso, el impacto sobre el manejo del paciente y las características técnicas de los aparatos utilizados.
Métodos
Se realizó una búsqueda en las bases de datos electrónicas PubMed y Google Scholar. No se aplicaron restricciones de idioma o fecha. Se incluyeron los informes de casos y artículos originales que describían el uso de aparatos de ultrasonido portátiles en PIBM, si dos revisores estaban de acuerdo sobre su relevancia basándose en las preguntas predefinidas de búsqueda.
Resultados
Se encontraron y revisaron 644 artículos, y se incluyeron 36 manuscritos en la revisión final. 27 estudios eran artículos de investigaciones originales y 9 eran informes de casos. Varios informes describan el diagnóstico exitoso y el manejo de condiciones difíciles, a menudo letales, utilizando equipos portátiles de ultrasonido. Estos equipos también han sido estudiados en pruebas de riesgo cardiaco, al igual que como herramientas de triaje rápido en áreas rurales y después de un desastre natural. La mayoría de las aplicaciones se centran en problemas obstétricos y abdominales. El ultrasonido portátil podría tener un impacto sobre el manejo clínico en hasta un 70% de todos los casos. Sin embargo, ningún ensayo aleatorizado y controlado ha evaluado el impacto del diagnóstico y el tratamiento guiado por ultrasonido en lugares con recursos limitados. Excluir aquellos artículos publicados en revistas que no figuran en las grandes bases de datos podría haber sesgado nuestros resultados. Nuestros hallazgos están limitados por la falta de evidencia de mayor calidad (ej. ensayos controlados).
Conclusiones
El uso de equipos de ultrasonido portátiles es exitoso para realizar el triaje, diagnóstico y tratamiento de pacientes con una variedad de problemas en PIBM. Sin embargo, la calidad de la evidencia actualmente disponible es baja. Existe una necesidad urgente de realizar ensayos clínicos grandes para evaluar el impacto de equipos de ultrasonido portátiles en PIBM.
Antimicrobial susceptibility testing (AST) results are crucial for timely administration of effective antimicrobial treatment, and, thus, should be made available to clinicians as fast as possible. ...In particular, increasing rates of multidrug-resistant organisms emphasize the need for rapid AST (rAST).
This article aims to provide microbiologists and clinicians with a critical overview of the current state of possibilities to accelerate AST. We also intend to discuss technical and strategic aspects of rAST, which may be helpful to academic researchers and assay developers in the industry.
We have reviewed literature on rAST methods and their implementation in routine diagnostics.
Phenotypic rAST is universal, mechanism-independent and allows exact categorization, but it demands time for the microorganisms to start the growth and to express the response to antibiotics. Detection of selected resistance mechanisms is more rapid, but the interpretation of its clinical impact is limited. Technical challenges of phenotypic rAST include inoculum effect, delayed expression of resistance, lag phase and initial biomass increase in susceptible isolates. Criteria for a successful rAST assay are ease of use, random access, capacity for simultaneous testing of multiple specimens, affordability and financial attractiveness for industry. Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS)-based AST seems to be particularly promising, as it can optimally be combined with MALDI-TOF MS identification. Direct testing from clinical specimens provides particularly early findings, with positive blood cultures being the most suitable specimen type. Polymicrobial samples and inoculum effect are serious obstacles for direct AST from other clinical specimens. Next to the technology improvement, optimization of pre-analytics and laboratory organization is essential.
It appears feasible to generate an AST report within the same working shift; however, only affordable and easy-to-use rAST technologies have a chance to enter broad diagnostic routine. Efforts should be made by industry, authorities and academia to enable wide dissemination of rAST in clinical diagnostics.
ABSTRACT Evidence for an extraterrestrial flux of high-energy neutrinos has now been found in multiple searches with the IceCube detector. The first solid evidence was provided by a search for ...neutrino events with deposited energies TeV and interaction vertices inside the instrumented volume. Recent analyses suggest that the extraterrestrial flux extends to lower energies and is also visible with throughgoing, -induced tracks from the Northern Hemisphere. Here, we combine the results from six different IceCube searches for astrophysical neutrinos in a maximum-likelihood analysis. The combined event sample features high-statistics samples of shower-like and track-like events. The data are fit in up to three observables: energy, zenith angle, and event topology. Assuming the astrophysical neutrino flux to be isotropic and to consist of equal flavors at Earth, the all-flavor spectrum with neutrino energies between 25 TeV and 2.8 PeV is well described by an unbroken power law with best-fit spectral index −2.50 0.09 and a flux at 100 TeV of . Under the same assumptions, an unbroken power law with index −2 is disfavored with a significance of 3.8 (p = 0.0066%) with respect to the best fit. This significance is reduced to 2.1 (p = 1.7%) if instead we compare the best fit to a spectrum with index −2 that has an exponential cut-off at high energies. Allowing the electron-neutrino flux to deviate from the other two flavors, we find a e fraction of 0.18 0.11 at Earth. The sole production of electron neutrinos, which would be characteristic of neutron-decay-dominated sources, is rejected with a significance of 3.6 (p = 0.014%).
We aimed to develop a universal phenotypic method, which allows easy and rapid antimicrobial susceptibility testing independently of underlying resistance mechanisms.
We established a novel ...direct-on-target microdroplet growth assay for the detection of antibiotic resistance within a few hours, which is based on matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS). The microorganisms were incubated with and without meropenem in nutrient broth as microdroplets directly on MALDI-TOF MS target. Subsequently, broth was separated from microbial cells by contacting the microdroplets with an absorptive material. The microorganisms grown in the presence of antibiotic were detected by MALDI-TOF MS. A total of 24 Klebsiella pneumoniae and 24 Pseudomonas aeruginosa isolates were used to assess performance for detection of meropenem resistance. The microdroplet volumes investigated were 2, 4, 6, 8 and 10 μL.
The best performance was achieved using 6-μL microdroplets. Applying this volume, all growth controls were successfully detected (definition of valid test), and all isolates were correctly categorized as susceptible or non-susceptible after an 18-h incubation. For K. pneumoniae, rate of valid tests, sensitivity and specificity all reached 100% after a 4-h incubation of 6-μL microdroplets. Using the same microdroplet volume for P. aeruginosa, incubation for 5 h resulted in 83.3% of valid tests with 100% sensitivity and 100% specificity.
We demonstrated easy, rapid and accurate resistance detection using carbapenem-resistant Gram-negative bacteria as an example. Our technology is suitable for automatization and expandable to further applications, e.g. simultaneous testing of multiple antibiotics as well as resistance determination directly from clinical samples.
The temperature and oxygen partial pressure (pO2) dependent electrical conductivity of LiNbO3, LiTaO3, LiNb1-xTaxO3 (LNT) solid solutions up to 900 °C is presented. The electrical conductivity is ...found to be isotropic up to about 700 °C. Different Nb/Ta ratios do not affect activation energies at temperatures below 600 °C, which suggests an identical conduction mechanism, namely the migration of Li ions by means of Li vacancies. Above this temperature, noticeable deviations in the conductivity of Nb rich samples emerge due to strongly increasing electronic contributions.
The pO2 dependent conductivity is strongly affected by the Nb/Ta ratio, enabling the tailoring of electrical properties through composition control. At low pO2, Nb rich LNT shows a much larger conductivity compared to LT. At 900 °C, conductivity of LT remains unaffected by pO2 down to 10−9 bar. The experimental findings can be understood based on a defect model that does not include the evaporation of Li2O. The latter is, therefore, assumed to play a minor role for the short-term experiments up to 900 °C.
•Comprehensive Investigation of electrical cunductivity in lithium niobate-tantalate (LNT) as a function of temperature and oxygen partial pressure.•Activation Energy Determination results in a difference above and below the Curie temperature.•Ionic and Electronic Contributions to electrical conductivity are found. The electronic impact dominates at low oxygen partial pressures.•Defect Models Validation aligns with the Li vacancy defect model.
We present results on searches for point-like sources of neutrinos using four years of IceCube data, including the first year of data from the completed 86 string detector. The total livetime of the ...combined data set is 1373 days. For an E super(-2) spectrum, the observed 90% C.L. flux upper limits are ~10 super(-12) TeV super(-1) cm super(-2) s super(-1) for energies between 1 TeV and 1 PeV in the northern sky and ~10 super(-11) TeV super(-1) cm super(-2) s super(-1) for energies between 100 TeV and 100 PeV in the southern sky. This represents a 40% improvement compared to previous publications, resulting from both the additional year of data and the introduction of improved reconstructions. In addition, we present the first results from an all-sky search for extended sources of neutrinos. We update the results of searches for neutrino emission from stacked catalogs of sources and test five new catalogs; two of Galactic supernova remnants and three of active galactic nuclei. In all cases, the data are compatible with the background-only hypothesis, and upper limits on the flux of muon neutrinos are reported for the sources considered.
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