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The KASCADE-Grande experiment has significantly contributed to the current knowledge about the energy spectrum and composition of cosmic rays for energies between the knee and the ankle. Meanwhile, post-LHC versions of the hadronic interaction models are available and used to interpret the entire data set of KASCADE-Grande. In addition, a new, combined analysis of both arrays, KASCADE and Grande, was developed significantly increasing the accuracy of the shower observables. First results of the new analysis with the entire data set of the KASCADE-Grande experiment will be the focus of this contribution.
Two-particle correlation functions of negative hadrons over wide phase space, and transverse mass spectra of negative hadrons and deuterons near mid-rapidity have been measured in central Pb+Pb collisions at 158 GeV per nucleon by the NA49 experiment at the CERN SPS. A novel Coulomb correction procedure for the negative two-particle correlations is employed making use of the measured oppositely charged particle correlation. Within an expanding source scenario these results are used to extract the dynamic characteristics of the hadronic source, resolving the ambiguities between the temperature and transverse expansion velocity of the source, that are unavoidable when single and two particle spectra are analysed separately. The source shape, the total duration of the source expansion, the duration of particle emission, the freeze-out temperature and the longitudinal and transverse expansion velocities are deduced.
We report measurements of Xi and Xi-bar hyperon absolute yields as a function of rapidity in 158 GeV/c Pb+Pb collisions. At midrapidity, dN/dy = 2.29 +/- 0.12 for Xi, and 0.52 +/- 0.05 for Xi-bar, leading to the ratio of Xi-bar/Xi = 0.23 +/- 0.03. Inverse slope parameters fitted to the measured transverse mass spectra are of the order of 300 MeV near mid-rapidity. The estimated total yield of Xi particles in Pb+Pb central interactions amounts to 7.4 +/- 1.0 per collision. Comparison to Xi production in properly scaled p+p reactions at the same energy reveals a dramatic enhancement (about one order of magnitude) of Xi production in Pb+Pb central collisions over elementary hadron interactions.
The directed and elliptic flow of protons and charged pions has been observed from the semi-central collisions of a 158 GeV/nucleon Pb beam with a Pb target. The rapidity and transverse momentum dependence of the flow has been measured. The directed flow of the pions is opposite to that of the protons but both exhibit negative flow at low pt. The elliptic flow of both is fairly independent of rapidity but rises with pt. PACS numbers: 25.75.-q, 25.75.Ld
Using the NA49 main TPC, the central production of hyperons has been measured in CERN SPS Pb - Pb collisions at 158 GeV c-1. The preliminary ratio, studied at 2.0 < y < 2.6 and 1 < pT < 3 GeV c-1, equals ~ (13 ± 4)% (systematic error only). It is compatible, within errors, with the previously obtained ratios for central S + S [1], S + W [2], and S + Au [3] collisions. The fit to the transverse momentum distribution resulted in an inverse slope parameter T of 297 MeV. At this level of statistics we do not see any noticeable enhancement of hyperon production with the increased volume (and, possibly, degree of equilibration) of the system from S + S to Pb + Pb. This result is unexpected and counterintuitive, and should be further investigated. If confirmed, it will have a significant impact on our understanding of mechanisms leading to the enhanced strangeness production in heavy-ion collisions.
Preliminary data on phi production in central Pb + Pb collisions at 158 GeV per nucleon are presented, measured by the NA49 experiment in the hadronic decay channel phi - K+K-. At mid-rapidity, the kaons were separated from pions and protons by combining dE/dx and time-of-flight information; in the forward rapidity range only dE/dx identification was used to obtain the rapidity distribution and a rapidity-integrated mt-spectrum. The mid-rapidity yield obtained was dN/dy = 1.85 ± 0.3 per event; the total phi multiplicity was estimated to be 5.0 ± 0.7 per event. Comparison with published pp data shows a slight, but not very significant strangeness enhancement.
The large acceptance TPCs of the NA49 spectrometer allow for a systematic multidimensional study of two-particle correlations in different part of phase space. Results from Bertsch-Pratt and Yano-Koonin-Podgoretskii parametrizations are presented differentially in transverse pair momentum and pair rapidity. These studies give an insight into the dynamical space-time evolution of relativistic Pb+Pb collisions, which is dominated by longitudinal expansion.
Lambda and Antilambda reconstruction in central Pb+Pb collisions using a time projection chamber
(1997)
The large acceptance time projection chambers of the NA49 experiment are used to record the trajectory of charged particles from Pb + Pb collisions at 158 GeV per nucleon. Neutral strange hadrons have been reconstructed from their charged decay products. To obtain distributions of Λ, and Ks0 in discrete bins of rapidity, y, and transverse momentum, pT, calculations have been performed to determine the acceptance of the detector and the efficiency of the reconstruction software as a function of both variables. The lifetime distributions obtained give values of cτ = 7.8 ± 0.6 cm for Λ and cτ = 2.5 ± 0.3 cm for Ks0, consistent with data book values.
Background: Juvenile dermatomyositis (JDM) is the most common inflammatory myopathy in childhood and a major cause of morbidity among children with pediatric rheumatic diseases. The management of JDM is very heterogeneous. The JDM working group of the Society for Pediatric Rheumatology (GKJR) aims to define consensus- and practice-based strategies in order to harmonize diagnosis, treatment and monitoring of JDM.
Methods: The JDM working group was established in 2015 consisting of 23 pediatric rheumatologists, pediatric neurologists and dermatologists with expertise in the management of JDM. Current practice patterns of management in JDM had previously been identified via an online survey among pediatric rheumatologists and neurologists. Using a consensus process consisting of online surveys and a face-to-face consensus conference statements were defined regarding the diagnosis, treatment and monitoring of JDM. During the conference consensus was achieved via nominal group technique. Voting took place using an electronic audience response system, and at least 80% consensus was required for individual statements.
Results: Overall 10 individual statements were developed, finally reaching a consensus of 92 to 100% regarding (1) establishing a diagnosis, (2) case definitions for the application of the strategies (moderate and severe JDM), (3) initial diagnostic testing, (4) monitoring and documentation, (5) treatment targets within the context of a treat-to-target strategy, (6) supportive therapies, (7) explicit definition of a treat-to-target strategy, (8) various glucocorticoid regimens, including intermittent intravenous methylprednisolone pulse and high-dose oral glucocorticoid therapies with tapering, (9) initial glucocorticoid-sparing therapy and (10) management of refractory disease.
Conclusion: Using a consensus process among JDM experts, statements regarding the management of JDM were defined. These statements and the strategies aid in the management of patients with moderate and severe JDM.
Introduction: This study presents our online-teaching material within the k-MED project (Knowledge in Medical Education) at the university of Marburg. It is currently organized in five e-learning modules: cytogenetics, chromosomal aberrations, formal genetics, fundamentals of molecular diagnostics, and congenital abnormalities and syndromes. These are basic courses intended to do the educational groundwork, which will enable academic teachers to concentrate on more sophisticated topics during their lectures. Methods: The e-learning modules have been offered to a large group of about 3300 students during four years at the Faculty of Medicine in Marburg. The group consists of science students (human biology) and medical students in the preclinical or the clinical period, respectively. Participants were surveyed on acceptance by evaluating user-tracking data and questionnaires. Results and Conclusion: Analysis of the evaluation data proofs the broad acceptance of the e-learning modules during eight semesters. The courses are in stable or even increasing use from winter term 2005/06 until spring term 2009. Conclusion: Our e-learning-model is broadly accepted among students with different levels of knowledge at the Faculty of Medicine in Marburg. If the e-learning courses are maintained thoroughly, minor adaptations can increase acceptance and usage even furthermore. Their use should be extended to the medical education of technical assistances and nurses, who work in the field of human genetics. Keywords: Human genetics, e-Learning, evaluation, multimedia
Welche Tiere und Pflanzen es auf unserer Erde überhaupt gibt und wie sie verbreitet sind, ist eine der Kardinalfragen biologischer Grundlagenforschung. Diese Erkenntnis hat sich gerade in den letzten Jahren auch in der Öffentlichkeit durchgesetzt und Biodiversität ist schon fast ein Modewort geworden. Die ungeheure Artenvielfalt der Insekten und hier auch ganz besonders der Käfer kann ohne die Mithilfe der sogenannten Liebhaber oder Amateure nicht erfasst werden. Solche Liebhaber sind eben nicht verschrobene Gestalten, die mit Schmetterlingsnetz und Botanisiertrommel durch Wald und Wiese streifen, sondern sie sind unverzichtbare Grundlagenforscher, die die Basis schaffen für alle weiterführenden biologischen Untersuchungen, wie beispielsweise über Bestandsveränderungen, Vergleich von Ökosystemen oder praktische Naturschutzarbeit. Dass dem so ist, haben Jürgen Frank und Eberhard Konzelmann mit dem vorliegenden Grundlagenwerk über die Käfer Baden-Württembergs eindruckvoll und beispielhaft bestätigt. Die Käfer sind eine der größten Organismen-Gruppen, die wir auf unserem Planeten kennen und sie besitzen eine große ökologische Plastizität in allen terrestrischen Lebensräumen, nur im Meer fehlen sie. Damit besitzen sie auch eine gute Indikatorfunktion und die Untersuchung der Käfergemeinschaften lässt auch Rückschlüsse auf andere Tier- und Pflanzengruppen zu. Das neue Verzeichnis belegt den aktuellen Bestand von rund 4800 Käferarten in Baden-Württemberg auf der Basis abgesicherter und nachprüfbarer Fundnachweise in den letzten 50 Jahren. Das sind mehr als 3/4 aller in Deutschland vorkommenden Arten. Die Arten werden nicht nur aufgelistet, sondern es wird die genaue Anzahl der Funde in den großen Naturräumen des Landes (Rheinebene, Schwarzwald, Neckarland, Schwäbische Alb und Oberschwaben) differenziert dokumentiert.
Einleitung: Die vorliegende Studie beschreibt unser Online-Lehrmaterial Humangenetik im Zusammenhang mit dem k-MED-Projekt (Knowledge in Medical Education) an der Philipps-Universität Marburg. Es besteht aus fünf E-Learning-Modulen: Zytogenetik, Chromosomenstörungen, Formalgenetik, Grundlagen der molekularen Diagnostik sowie Kongenitale Abnormitäten und Fehlbildungssyndrome. Diese E-Module sollen ein einheitliches Wissensniveau der Studierenden gewährleisten und die Dozenten in der Präsenzlehre entlasten. Methoden: Die fünf E-Learning-Module Humangenetik wurden auf freiwilliger Basis einer großen Personengruppe von ca. 3300 Studierenden am Fachbereich Humanmedizin der Universität Marburg über eine Dauer von vier Jahren angeboten. Die Teilnehmer bestanden aus Naturwissenschaftlern (Humanbiologie) im 5. Fachsemester und Studierenden der Humanmedizin, die sich entweder in der Vorklinik (1. Semester) oder im klinischen Studienabschnitt (7./8. Semester) befanden. Von diesen wurden Daten zur Akzeptanz in Form von Usertrackingdaten und klausur-begleitenden Fragebögen erhoben. Ergebnisse und Schlussfolgerung: Die Evaluation zeigte eine breite Akzeptanz unserer Lehrmodule über einen Zeitraum von acht Semestern. Obwohl das Angebot freiwillig ist, werden die Online-Kurse Humangenetik konstant oder sogar in zunehmendem Maße zwischen Wintersemester 2005/06 und Sommersemester 2009 genutzt. Fazit: Unser E-Learning-Modell Humangenetik wird von Studierenden aus unterschiedlichen Semestern und Studiengängen am Fachbereich Humanmedizin gut angenommen und genutzt. Bei sorgfältiger Pflege der Online-Kurse steigern moderate Anpassungen sowohl Akzeptanz als auch Benutzungshäufigkeit in signifikanter Weise. Die Anwendung der E-Learning Module erscheint uns auch in der Ausbildung von MTAs oder Pflegekräften sinnvoll, um ein ausreichendes Grundwissen in Humangenetik zu gewährleisten. Schlüsselwörter: Humangenetik, Evaluation, Multimedia, E-Learning
Modelling protein structure seems a challenging enterprise because the number of structure parameters required ordinarily exceeds the amount of independent data points available from experimental observations. Expressing the predominant conformation of a protein in terms of a geometry model, a polypeptide chain consisting of N atoms would command 3N – 6 Cartesian coordinates be fixed. Even for small proteins, this becomes a daunting number. Fortunately, so-called holonomic constraints limit the number of variables, leaving substantially fewer, truly relevant parameters for folding the polypeptide chain into its native tertiary structure. For example, adjusting bond lengths and the many angles between the covalent bonds connecting the atoms is of little concern and appropriate standard values can be inserted from tableworks (Pople & Gordon, 1967; Engh & Huber, 1991, 2006). Table 1 exemplifies for the 147-residue protein Desulfovibrio vulgaris flavodoxin how the number of truly independent internal rotational degrees of freedom amounts to less than one-tenth of the Cartesian coordinate set size...
Am 6. Mai fand an der Goethe-Universität der Auftakt der neuen Veranstaltungsreihe „Helmholtz &Uni“ statt, mit der die Helmholtz-Gemeinschaft gemeinsam mit Universitäten den Dialog über das Zusammenspiel von Universitäten und der außeruniversitären Forschung initiieren möchte. Prof. Jürgen Mlynek, Präsident der HelmholtzGemeinschaft, diskutierte mit Universitätspräsident Prof. Werner Müller-Esterl, dem Hirnforscher Prof. Wolf Singer und der Biochemikerin Prof. Stefanie Dimmeler. Wir haben im Vorfeld der Veranstaltung Prof. Mlynek einige Fragen zu dem kürzlich veröffentlichten Positionspapier gestellt.
Background: To assess the influence of ridge preservation procedures on the healing of extraction sockets under antiresorptive therapy.
Material and Methods: A total of 10 Dutch Belted rabbits were randomly allocated to either the intravenous administration of amino‐bisphosphonate (zoledronic acid) (Za) (n = 5) or a negative control group (no Za [nZa]) (n = 5). At 6 months, the mandibular and maxillary molars were extracted and the four experimental sites randomly allocated to the following subgroups: (a) socket grafting using a collagen‐coated natural bone mineral (BOC) + primary wound closure, (b) coronectomy (CO), or (c) spontaneous healing + primary wound closure (SP). Za medication was continued for another 4 months. Histomorphometrical analyses considered, for example, crestal hard tissue closure of the extraction site (C) and mineralized tissue (MT) formation.
Results: Za‐SP was associated with an incomplete median C (31.76% vs 100% in nZa‐SP) and signs of bone arrosion along the confines of the socket. BOC had no major effects on increases in C and MT values in the Za group. CO commonly resulted in an encapsulation and partial replacement resorption of residual roots by MT without any histological signs of osteonecrosis.
Conclusions: (a) Za‐SP was commonly associated with a compromised socket healing and signs of osteonecrosis, (b) BOC had no major effect on socket healing in the Za group, and (c) CO at noninfected teeth might be a feasible measure for the prevention of a Za‐related osteonecrosis of the jaw.
Der Nationale Aktionsplan für Menschen mit Seltenen Erkrankungen (SE) enthält 52 konkrete Maßnahmen, u. a. in den Handlungsfeldern Versorgung, Forschung, Diagnose und Informationsmanagement. Mit dem Ziel, langfristig die Qualität und Interoperabilität von nationalen Registern zu erhöhen, sieht Maßnahmenvorschlag 28 die Etablierung einer Strategiegruppe „Register für Seltene Erkrankungen“ vor. Diese Strategiegruppe hat 2016 ihre Arbeit aufgenommen. Sie berichtet hier über Entwicklungen auf nationaler und internationaler Ebene, um Empfehlungen für nationale Initiativen daraus abzuleiten.
Zusätzlich werden die Konsentierung und Implementierung sowie mit der Zeit ggf. die Anpassung eines Minimaldatensatzes zur Verwendung in Registern für Seltene Erkrankungen erläutert. Zusätzlich werden die verwendeten Datenelemente bzw. -schemata in einem sog. Metadata Repository abgebildet. Dieses Positionspapier wurde durch die Strategiegruppe sowie weitere Autoren erarbeitet und innerhalb der Gruppe konsentiert. Es wird als Konzeptpapier zum Aufbau und Betrieb von Registern der Strategiegruppe „Register“ veröffentlicht.
Implementing an automated monitoring process in a digital, longitudinal observational cohort study
(2021)
Background: Clinical data collection requires correct and complete data sets in order to perform correct statistical analysis and draw valid conclusions. While in randomized clinical trials much effort concentrates on data monitoring, this is rarely the case in observational studies- due to high numbers of cases and often-restricted resources. We have developed a valid and cost-effective monitoring tool, which can substantially contribute to an increased data quality in observational research.
Methods: An automated digital monitoring system for cohort studies developed by the German Rheumatism Research Centre (DRFZ) was tested within the disease register RABBIT-SpA, a longitudinal observational study including patients with axial spondyloarthritis and psoriatic arthritis. Physicians and patients complete electronic case report forms (eCRF) twice a year for up to 10 years. Automatic plausibility checks were implemented to verify all data after entry into the eCRF. To identify conflicts that cannot be found by this approach, all possible conflicts were compiled into a catalog. This “conflict catalog” was used to create queries, which are displayed as part of the eCRF. The proportion of queried eCRFs and responses were analyzed by descriptive methods. For the analysis of responses, the type of conflict was assigned to either a single conflict only (affecting individual items) or a conflict that required the entire eCRF to be queried.
Results: Data from 1883 patients was analyzed. A total of n = 3145 eCRFs submitted between baseline (T0) and T3 (12 months) had conflicts (40–64%). Fifty-six to 100% of the queries regarding eCRFs that were completely missing were answered. A mean of 1.4 to 2.4 single conflicts occurred per eCRF, of which 59–69% were answered. The most common missing values were CRP, ESR, Schober’s test, data on systemic glucocorticoid therapy, and presence of enthesitis.
Conclusion: Providing high data quality in large observational cohort studies is a major challenge, which requires careful monitoring. An automated monitoring process was successfully implemented and well accepted by the study centers. Two thirds of the queries were answered with new data. While conventional manual monitoring is resource-intensive and may itself create new sources of errors, automated processes are a convenient way to augment data quality.