Incompatibility of different customary kaon phase convention

The conventions that Wu and Yang assumed for the kaon phases in the context of $CP$ symmetrical two-pion decay channels fix the relative kaon phase. This fact, apparently not emphasized sufficiently in the past, has recently been overlooked by Hayakawa and Sanda. In particular, Wu and Yang fix the relative phase to a different value than the one resulting from the convention $CP|K^{0}\rangle = |\overline{K^{0}}\rangle$. The difference between the two values is made up of possible contributions from $CPT$- and direct $CP$-violations during the decay of a kaon into a two-pion state of isospin zero.Comment: 5 pages, LaTe

Kognitive Verzerrungen im strategischen Entscheidungsprozess

Strategische Entscheidungen bilden seit Jahrzehnten einen wesentlichen Schwerpunkt der Managementforschung. Es existieren inzwischen zahlreiche Modelle des strategischen Entscheidungsprozesses, die jeweils unterschiedliche Schwerpunkte setzen. Doch trotz dieser beachtlichen Modellvielfalt lassen sich wesentliche Elemente realer Entscheidungssituationen in Unternehmen nicht ausreichend erklären. So weicht das Verhalten von Entscheidungsträgern oft deutlich und systematisch von dem ab, was die normative Entscheidungstheorie erwarten ließe. Einen wesentlichen Beitrag zur Erklärung dieser Abweichungen kann die Berücksichtigung kognitiver Verzerrungen liefern. Kognitive Verzerrungen entstehen aufgrund der kognitiven Limitierungen, denen Entscheidungsträger angesichts der hohen Komplexität und Unsicherheit strategischer Entscheidungen ausgesetzt sind. Die vorliegende Arbeit gibt einen Überblick über wesentliche kognitive Verzerrungen, die den strategischen Entscheidungsprozess beeinflussen können. Dazu wird durch eine systematische Auswertung hochqualitativer Zeitschriften der aktuelle Forschungsstand heraus- gearbeitet und dargestellt. Unter Einbeziehung kognitionspsychologischer Forschungsergebnisse wird entlang eines idealtypischen strategischen Entscheidungsprozesses erläutert, wie sich kognitive Verzerrungen auf die einzelnen Phasen strategischer Entscheidungen auswirken können. Es wird deutlich, dass Entscheidungsträger in strategischen Entscheidungssituationen zahlreichen kognitiven Verzerrungen unterliegen, die mitunter zu schweren Fehlentscheidungen führen können. Die explizite Berücksichtigung kognitiver Verzerrungen kann daher einen wesentlichen Beitrag zur Verbesserung der Qualität strategischer Entscheidungen leisten und damit zum langfristigen Erfolg eines Unternehmens beitragen.Keywords: Strategisches Entscheidungsverhalten, Kognitive Verzerrung, Kognitiver Bias, Behavioral Strategy, Strategisches Managemen

Tick-Borne Encephalitis Virus: A General Overview

Tick-borne encephalitis (TBE) virus is classified as one species with three subtypes, namely the European subtype, the Siberian subtype and the Far Eastern subtype. TBE is distributed in an endemic pattern of so-called natural foci over a wide geographical area from Western Europe to the northern part of Japan. It is the most important flavivirus infection of the central nervous system in Europe and Russia, with about 13,000 estimated human cases per year. The epidemiology of TBE is closely related to the ecology and biology of ixodid ticks. In nature, TBE virus is propagated in a cycle involving permanently infected ticks and wild vertebrate hosts. Currently, the diagnosis of TBE is mainly based on the detection of specific antibodies in serum and cerebrospinal fluid. No specific treatment for the disease is available to date, but it can be prevented by active immunization

First international diagnostic accuracy study for the serological detection of West Nile virus infection

<p>Abstract</p> <p>Background</p> <p>The diagnosis of an acute or convalescent West Nile (WN) virus infection can be confirmed by various serological assays such as enzyme immunoassay (EIA), immunofluorescence assay (IFA), or neutralisation test (NT) which are conducted by a growing number of laboratories. However, as the degree of proficiency may vary between laboratories, quality control measures for laboratory diagnostics are essential.</p> <p>Methods</p> <p>We have performed an external quality assurance (EQA) programme for the serological detection of WN virus infection to assess the diagnostic quality of laboratories. The participating laboratories received a proficiency panel of 10 coded lyophilised test samples comprising four antisera positive for WN antibodies as positive controls, three antisera positive for antibodies against other heterologous flaviviruses plus one multireactive unspecific serum as specificity controls, and two negative serum samples.</p> <p>Results</p> <p>Twenty-seven laboratories from 20 different countries in Europe, the Middle East, the Americas and Africa participated in this EQA programme. Applying the proficiency criteria of this study, only eight laboratories correctly analysed all samples with their respective EIA, IFA or NT methods. Eighteen laboratories correctly identified between 77.8 and 90% of the samples, and one laboratory identified only 70% correctly with a clear need to eliminate cross-reactivity with other antisera, particularly those elicited by yellow fever virus. Differentiation between the results for IgM and IgG was considered separately and revealed that IgM-antibodies were detected less frequently than IgG-antibodies (p < 0.001). However, the assay used was not a significant technical factor influencing laboratory performance.</p> <p>Conclusion</p> <p>The EQA programme provides information on the quality of different serological assays used by the participating laboratories and indicates that most need to improve their assays, in particular to avoid cross-reactions with antibodies to heterologous flaviviruses.</p

Second international diagnostic accuracy study for the serological detection of west nile virus infection.

Background: In recent decades, sporadic cases and outbreaks in humans of West Nile virus (WNV) infection have increased. Serological diagnosis of WNV infection can be performed by enzyme-linked immunosorbent assay (ELISA), immunoflu- orescence assay (IFA) neutralization test (NT) and by hemagglutination-inhibition assay. The aim of this study is to collect updated information regarding the performance accuracy of WNV serological diagnostics. Methodology/Principal findings: In 2011, the European Network for the Diagnostics of Imported Viral Diseases- Collaborative Laboratory Response Network (ENIVD-CLRN) organized the second external quality assurance (EQA) study for the serological diagnosis of WNV infection. A serum panel of 13 samples (included sera reactive against WNV, plus specificity and negative controls) was sent to 48 laboratories involved in WNV diagnostics. Forty-seven of 48 laboratories from 30 countries participated in the study. Eight laboratories achieved 100% of concurrent and correct results. The main obstacle in other laboratories to achieving similar performances was the cross-reactivity of antibodies amongst heterologous flaviviruses. No differences were observed in performances of in-house and commercial test used by the laboratories. IFA was significantly more specific compared to ELISA in detecting IgG antibodies. The overall analytical sensitivity and specificity of diagnostic tests for IgM detection were 50% and 95%, respectively. In comparison, the overall sensitivity and specificity of diagnostic tests for IgG detection were 86% and 69%, respectively. Conclusions/Significance: This EQA study demonstrates that there is still need to improve serological tests for WNV diagnosis. The low sensitivity of IgM detection suggests that there is a risk of overlooking WNV acute infections, whereas the low specificity for IgG detection demonstrates a high level of cross-reactivity with heterologous flaviviruse

International External Quality Assessment of Molecular Detection of Rift Valley Fever Virus

Rift Valley fever (RVF) is a viral zoonosis that primarily affects animals resulting in considerable economic losses due to death and abortions among infected livestock. RVF also affects humans with clinical symptoms ranging from an influenza-like illness to a hemorrhagic fever. Over the past years, RVF virus (RVFV) has caused severe outbreaks in livestock and humans throughout Africa and regions of the world previously regarded as free of the virus. This situation prompts the need to evaluate the diagnostic capacity and performance of laboratories worldwide. Diagnostic methods for RVFV detection include virus isolation, antigen and antibody detection methods, and nucleic acid amplification techniques. Molecular methods such as reverse-transcriptase polymerase chain reaction and other newly developed techniques allow for a rapid and accurate detection of RVFV. This study aims to assess the efficiency and accurateness of RVFV molecular diagnostic methods used by expert laboratories worldwide. Thirty expert laboratories from 16 countries received a panel of 14 samples which included RVFV preparations representing several genetic lineages, a specificity control and negative controls. In this study we present the results of the first international external quality assessment (EQA) for the molecular diagnosis of RVF. Optimal results were reported by 64% of the analyses, 21% of the analyses achieved acceptable results and 15% of the results revealed that there is need for improvement. Evenly good performances were achieved by specific protocols which can therefore be recommended as an accurate molecular protocol for the diagnosis of RVF. Other protocols showed uneven performances revealing the need for improved optimization and standardization of these protocols

Rickettsia aeschlimannii in Hyalomma marginatum Ticks, Germany

To the Editor: Rickettsia spp. of the spotted fever group cause worldwide emerging human infections known as tick-borne rickettsioses (1). Data on the occurrence and prevalence of Rickettsia in Germany are still limited (2). Six Rickettsia species have been reported to date (2). R. helvetica, R. felis, R. massiliae, and R. monacensis were detected with a relatively low prevalence in Ixodes ricinus ticks collected in southern Germany (2); R. raoultii was identified with high prevalence in the rapidly expanding area where D. reticulatus ticks are found (2). R. raoultii was recently recognized as an agent of tick-borne lymphadenopathy/Dermacentor-borne necrosis and erythema lymphadenopathy (3). Low prevalence of another tick-borne lymphadenopathy agent, R. slovaca, in Dermacentor marginatus ticks collected in southern Germany was recently reported (4)

2nd International External Quality Control Assessment for the Molecular Diagnosis of Dengue Infections

Dengue viruses (DENV) are the most widespread arthropod-borne viruses which have shown an unexpected geographic expansion, as well as an increase in the number and severity of outbreaks in the last decades. In this context, the accurate diagnosis and reliable surveillance of dengue infections are essential. The laboratory diagnosis of dengue relies on the use of several methods detecting markers of DENV infection present in patient serum. Molecular diagnosis methods are usually rapid, sensitive, and simple when correctly standardized. Moreover, PCR-based diagnosis techniques are able to readily detect DENV during the acute phase of the disease and may assume an important role in dengue diagnosis and surveillance. Different reverse transcriptase PCR (RT-PCR) methods have been developed and are currently available and should be standardized in each laboratory to maintain high quality performance. In this work an External quality assessment (EQA) activity has been carried out to evaluate the accuracy and quality of laboratory data for the molecular diagnosis and surveillance of dengue, which involved worldwide dengue reference laboratories. In conclusion, RT-PCR techniques for dengue diagnosis applied by the participating laboratories demonstrated the need of further improvement in most laboratories

Coordinated Implementation of Chikungunya Virus Reverse Transcription–PCR

A preformulated chikungunya virus real-time reverse transcription–PCR, quality-confirmed oligonucleotides, and noninfectious virus controls were distributed by the European Network for the Diagnosis of Imported Viral Diseases. An international proficiency study with 31 participants demonstrated that ad hoc implementation of molecular diagnostics was feasible and successful