Die asymptotische Verteilung der Spannweite bei Zufallsgrößen mit paarweise identischer Korrelation

Ein k-variates Einzelexperiment wird n-mal unabhängig wiederholt; die Ergebnisse werden summiert. Gesucht ist die Wahrscheinlichkeitsverteilung für die Spannweite der k Summen. Eine derartige Fragestellung ergibt sich etwa bei statistischen Tests zu Multinomial- oder Urnenexperimenten, wenn Alternativ-Verfahren zu den klassischen Chi-Quadrat-Tests gesucht werden. Die Untersuchung von Spannweitenverteilungen beschränkt sich allerdings in der Literatur vornehmlich auf den Fall, dass die der Spannweitenbildung zugrunde liegenden Zufallsvariablen stochastisch unabhängig und identisch verteilt sind. Im vorliegenden Arbeitsbericht werden einige Überlegungen für den Fall durchgeführt, dass eine einfache Abhängigkeitsstruktur innerhalb des Einzelexperimentes vorliegt. Es zeigt sich, dass asymptotisch bis aus einen Skalenfaktor die selbe Spannweitenverteilung wie im u.i.v-Fall vorliegt.<br/

A Central Limit Theorem for the average target hitting time for a random walk on a random graph

Consider a simple random walk on a realization of an Erd\H{o}s-R\'enyi graph. Assume that it is asymptotically almost surely (a.a.s.) connected. Conditional on an eigenvector delocalization conjecture, we prove a Central Limit Theorem (CLT) for the average target hitting time. By the latter we mean the expected time it takes the random walk on average to first hit a vertex $j$ when starting in a fixed vertex $i$. The average is taken with respect to $\pi_i$, the invariant measure of the random walk

Exploring the role of the microbiota: in defence against Clostridioides difficile and multidrug resistant Gram-negatives

Antibiotics provided humanity resilience to the majority of bacterial infections. An important trade-off is the emergence of antimicrobial resistance, and a diminished and perturbed microbiota, resulting in an increased susceptibility for Clostridioides difficile infections. For both C. difficile and multidrug resistant micro-organisms (MDRO), asymptomatic colonisation of the gut plays an important role in the development of infection. The aim of this thesis is to better understand the role of the microbiota in defence against infections with C. difficile and MDRO. The first part describes the epidemiology and detection of asymptomatically colonized individuals. It concludes that though asymptomatic colonization of MDRO and C. difficile can become a nidus for nosocomial (hospital) infection and transmission, its prevalence is still low in the Netherlands. The second part of this thesis focuses on eradication and/or treatment of these micro-organisms with ‘fecal microbiota transplantation’ of healthy donor feces. It describes the establishment of the Netherlands Donor Feces Bank, and the research, experiences and successes of FMT in the treatment of patients with recurrent C. difficile infections and MDRO. The experience of this thesis may help the establishment, utilization, standardization and maturation of stool banks and research institutes of the next-generation of microbiota modifying therapies. </p

COUNTER & SUSHI: Standards for Subscription Electronic Resource Usage Data and Its Delivery

This poster describes two standards utilized in the reporting and delivery of usage data of electronic resources: Counting Online Usage of Networked Electronic Resources (COUNTER) and the Standardized Usage Statistics Harvesting Initiative (SUSHI) Protocol. The first standard is comprised of a Code of Practices (COP) for creating standardized reports for libraries; the second is a protocol for the automated request and retrieval of usage data reports. These initiatives hold promise in stream-lining, for libraries, the process of compiling and analyzing usage statistics of electronic resources obtained from various vendors. A brief analysis of vendor participation in the latest release of the COUNTER COP/SUSHI will be included

European Society of Clinical Microbiology and Infectious Diseases: update of the diagnostic guidance document for Clostridium difficile infection.

In 2009 the first European Society of Clinical Microbiology and Infectious Diseases (ESCMID) guideline for diagnosing Clostridium difficile infection (CDI) was launched. Since then newer tests for diagnosing CDI have become available, especially nucleic acid amplification tests. The main objectives of this update of the guidance document are to summarize the currently available evidence concerning laboratory diagnosis of CDI and to formulate and revise recommendations to optimize CDI testing. This update is essential to improve the diagnosis of CDI and to improve uniformity in CDI diagnosis for surveillance purposes among Europe. An electronic search for literature concerning the laboratory diagnosis of CDI was performed. Studies evaluating a commercial laboratory test compared to a reference test were also included in a meta-analysis. The commercial tests that were evaluated included enzyme immunoassays (EIAs) detecting glutamate dehydrogenase, EIAs detecting toxins A and B and nucleic acid amplification tests. Recommendations were formulated by an executive committee, and the strength of recommendations and quality of evidence were graded using the Grades of Recommendation Assessment, Development and Evaluation (GRADE) system. No single commercial test can be used as a stand-alone test for diagnosing CDI as a result of inadequate positive predictive values at low CDI prevalence. Therefore, the use of a two-step algorithm is recommended. Samples without free toxin detected by toxins A and B EIA but with positive glutamate dehydrogenase EIA, nucleic acid amplification test or toxigenic culture results need clinical evaluation to discern CDI from asymptomatic carriage

Clinical Application and Potential of Fecal Microbiota Transplantation

Molecular basis of bacterial pathogenesis, virulence factors and antibiotic resistanc

Oral Polio Vaccine Influences the Immune Response to BCG Vaccination. A Natural Experiment

Background: Oral polio vaccine (OPV) is recommended to be given at birth together with BCG vaccine. While we were conducting two trials including low-birth-weight (LBW) and normal-birth-weight (NBW) infants in Guinea-Bissau, OPV was not available during some periods and therefore some infants did not receive OPV at birth, but only BCG. We investigated the effect of OPV given simultaneously with BCG at birth on the immune response to BCG vaccine. Methods and Findings: We compared the in vitro and the in vivo response to PPD in the infants who received OPV and BCG with that of infants who received BCG only. At age 6 weeks, the in vitro cytokine response to purified protein derivate (PPD) of M. Tuberculosis was reduced in LBW and NBW infants who had received OPV with BCG. In a pooled analysis receiving OPV with BCG at birth was associated with significantly lower IL-13 (p = 0.041) and IFN-gamma (p = 0.004) and a tendency for lower IL-10 (p = 0.054) in response to PPD. Furthermore, OPV was associated with reduced in vivo response to PPD at age 2 months, the prevalence ratio (PR) of having a PPD reaction being 0.75 (0.58-0.98), p = 0.033, and with a tendency for reduced likelihood of having a BCG scar (0.95 (0.91-1.00), p = 0.057)). Among children with a scar, OPV was associated with reduced scar size, the regression coefficient being -0.24 (-0.43-0.05), p = 0.012. Conclusions: This study is the first to address the consequences for the immune response to BCG of simultaneous administration with OPV. Worryingly, the results indicate that the common practice in low-income countries of administering OPV together with BCG at birth may down-regulate the response to BCG vaccine

Mechanistic Insights in the Success of Fecal Microbiota Transplants for the Treatment of Clostridium difficile Infections

Molecular basis of bacterial pathogenesis, virulence factors and antibiotic resistanc