5,503 research outputs found
Does the DNA barcoding gap exist? – a case study in blue butterflies (Lepidoptera: Lycaenidae)
BACKGROUND: DNA barcoding, i.e. the use of a 648 bp section of the mitochondrial gene cytochrome c oxidase I, has recently been promoted as useful for the rapid identification and discovery of species. Its success is dependent either on the strength of the claim that interspecific variation exceeds intraspecific variation by one order of magnitude, thus establishing a "barcoding gap", or on the reciprocal monophyly of species. RESULTS: We present an analysis of intra- and interspecific variation in the butterfly family Lycaenidae which includes a well-sampled clade (genus Agrodiaetus) with a peculiar characteristic: most of its members are karyologically differentiated from each other which facilitates the recognition of species as reproductively isolated units even in allopatric populations. The analysis shows that there is an 18% overlap in the range of intra- and interspecific COI sequence divergence due to low interspecific divergence between many closely related species. In a Neighbour-Joining tree profile approach which does not depend on a barcoding gap, but on comprehensive sampling of taxa and the reciprocal monophyly of species, at least 16% of specimens with conspecific sequences in the profile were misidentified. This is due to paraphyly or polyphyly of conspecific DNA sequences probably caused by incomplete lineage sorting. CONCLUSION: Our results indicate that the "barcoding gap" is an artifact of insufficient sampling across taxa. Although DNA barcodes can help to identify and distinguish species, we advocate using them in combination with other data, since otherwise there would be a high probability that sequences are misidentified. Although high differences in DNA sequences can help to identify cryptic species, a high percentage of well-differentiated species has similar or even identical COI sequences and would be overlooked in an isolated DNA barcoding approach
Zug in den Süden : wohin fliegen Große Brachvögel vom badischen Oberrhein nach der Brutzeit?
Die Mauser- und Überwinterungsgebiete der süddeutschen Brutvögel des Großen Brachvogels liegen an der Atlantikküste Frankreichs und der Iberischen Halbinsel, individuelle Unterschiede sowie Populationsunterschiede sind jedoch nicht bekannt. Daher wurde in einem Pilotversuch am 20. Mai 2008 ein brütendes Weibchen in einem Brutgebiet am badischen Oberrhein mit einem Satellitensender versehen. Das Weibchen zog am 8. Juni 2008 vermutlich in einem Direktflug von 1020 km in west-süd-westlicher Richtung an die kantabrische Atlantikküste. Signale wurden bis zum 9. Oktober 2008 empfangen.The moulting and wintering sites of Curlews breeding in southwestern Germany are situated at the atlantic coast of France and the Iberian Peninsula; so far, there are no indications of individual or population-specific differences in site choice. During a pilot study to test individual site choice, a breeding female from our study site at the upper Rhine in Baden was equipped with a satellite transmitter on 20 May 2008. The female started her migration on 8 June 2008, flying probably non-stop for 1200 km in westsouth-westerly direction to the Cantabrian coast, from were signals were received until 9 October 2008
Eine Analyse der fischereibiologischen und fischereilichen Verhältnisse in einem für die Ölförderung genutzten Offshore-Bereich des deutschen Ostseegebiets : eine Studie, durchgeführt mit Unterstützung des Konsortium Deutsche TEXACO/Wintershall A.G.
Forcierte physische Aktivität nach operativer Frakturstabilisierung hat im Mausmodell keinen Einfluss auf die Knochenbruchheilung
In den letzten Jahrzehnten wurde in vielfachen klinischen und experimentellen Arbeiten der Effekt von körperlicher Aktivität auf die Frakturheilung dargestellt. Hierbei konnte gezeigt werden, dass physische Aktivität und mechanische Frakturbelastung einen entscheidenden Einfluss auf Verlauf und Qualität der Frakturheilung haben. Während bislang fast ausschließlich die Mechanobiologie im Frakturspalt als wichtiger Einflussfaktor hinsichtlich der Hemmung bzw. Beschleunigung der Knochenbruchheilung untersucht wurde, wurde die
systemische Rolle körperlicher Aktivität während der Frakturheilung unseres Wissens nach nicht experimentell analysiert.
Ziel der hier vorgestellten Studie war es daher, interfragmentäre Relativbewegungen im Frakturspalt durch die Entwicklung einer rotations- und achsstabilen Osteosynthesetechnik für das Mäusefemur zu minimieren und somit den mechanobiologie-unabhängigen Effekt physischer Aktivität auf die Knochenbruchheilung an der Maus zu untersuchen.
Nach zwei- und fünfwöchigem täglichem Laufradtraining konnten wir in der histomorphometrischen und biomechanischen Auswertung des Frakturkallus weder eine Beschleunigung noch eine Hemmung der Frakturheilung beobachten.
Korrespondierend damit zeigten Western Blot Analysen des Kallus keine vermehrte Expression des Proliferationsmarkers PCNA und des angio- sowie osteogenen Wachstumsfaktors VEGF.
Somit ziehen wir die Schlussfolgerung, dass vermehrte körperliche Aktivität unter Ausschluss mechanobiologischer Einflussfaktoren keine Auswirkung auf die Knochenbruchheilung hat. Gleichzeitig unterstreichen unsere Ergebnisse den wichtigen Einfluss der Osteosynthesetechnik und relativieren die systemische Bedeutung körperlicher Aktivität auf die Frakturheilung.The aim of the present study was to analyse the systemic biological effect of increased physical exercise on fracture healing. We used a very stable fracture fixation technique to minimise the biomechanical impact of exercise on the interfragmentary environment and thereby to focus on the systemic biological effect of exercise on bone repair. We feel that it is important to distinguish between the local biomechanical effect of exercise on the fracture gap and the systemic biological effect of exercise on the total organism, which includes e.g., changes in blood circulation, metabolic conditions, and tissue oxygenation.
Two groups of SKH mice were studied. Animals of the first group (n=36) were housed in cages supplied with a running wheel, while mice of the second group (n=37) were housed in standard cages for control. Using a closed femur fracture model, bone repair was analysed by histomorphometry and biomechanical testing at 2 and 5 weeks. At 2 weeks, we additionally evaluated the expression of the proliferation marker PCNA (proliferating cell nuclear antigen) and the angiogenic and osteogenic growth factor VEGF (vascular endothelial growth factor). To standardise the mechanical conditions in the fracture gap, we used an intramedullary compression screw for stable fracture fixation.
Each mouse of the exercise group run a mean total distance of 23.5 km after 2 weeks and 104.3 km after 5 weeks. Histomorphometric analysis of the size and the tissue composition of the callus could not reveal significant differences between mice undergoing exercise and controls. Accordingly, biomechanical testing showed a comparable torsional stiffness, peak rotation angle, and load at failure of the healing bones in the two groups. The expression of PCNA and VEGF did also not differ between mice of the exercise group and controls.
We conclude that increased exercise does not affect bone repair after stable fracture fixation
Psychoanalytic and cognitive-behavior therapy of chronic depression : study protocol for a randomized controlled trial
Background: Despite limited effectiveness of short-term psychotherapy for chronic depression, there is a lack of trials of long-term psychotherapy. Our study is the first to determine the effectiveness of controlled long-term psychodynamic and cognitive-behavioral (CBT) treatments and to assess the effects of preferential vs. randomized assessment.
Methods/design: Patients are assigned to treatment according to their preference or randomized (if they have no clear preference). Up to 80 sessions of psychodynamic or psychoanalytically oriented treatments (PAT) or up to 60 sessions of CBT are offered during the first year in the study. After the first year, PAT can be continued according to the ‘naturalistic’ usual method of treating such patients within the system of German health care (normally from 240 up to 300 sessions over two to three years). CBT therapists may extend their treatment up to 80 sessions, but focus mainly maintenance and relapse prevention. We plan to recruit a total of 240 patients (60 per arm). A total of 11 assessments are conducted throughout treatment and up to three years after initiation of treatment. The primary outcome measures are the Quick Inventory of Depressive Symptoms (QIDS, independent clinician rating) and the Beck Depression Inventory (BDI) after the first year.
Discussion: We combine a naturalistic approach with randomized controlled trials(RCTs)to investigate how effectively chronic depression can be treated on an outpatient basis by the two forms of treatment reimbursed in the German healthcare system and we will determine the effects of treatment preference vs. randomization
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Evaluation of fishway design for German Federal Waterways by means of fish studies
Real-world Health Data and Precision for the Diagnosis of Acute Kidney Injury, Acute-on-Chronic Kidney Disease, and Chronic Kidney Disease: Observational Study.
BACKGROUND
The criteria for the diagnosis of kidney disease outlined in the Kidney Disease: Improving Global Outcomes guidelines are based on a patient's current, historical, and baseline data. The diagnosis of acute kidney injury, chronic kidney disease, and acute-on-chronic kidney disease requires previous measurements of creatinine, back-calculation, and the interpretation of several laboratory values over a certain period. Diagnoses may be hindered by unclear definitions of the individual creatinine baseline and rough ranges of normal values that are set without adjusting for age, ethnicity, comorbidities, and treatment. The classification of correct diagnoses and sufficient staging improves coding, data quality, reimbursement, the choice of therapeutic approach, and a patient's outcome.
OBJECTIVE
In this study, we aim to apply a data-driven approach to assign diagnoses of acute, chronic, and acute-on-chronic kidney diseases with the help of a complex rule engine.
METHODS
Real-time and retrospective data from the hospital's clinical data warehouse of inpatient and outpatient cases treated between 2014 and 2019 were used. Delta serum creatinine, baseline values, and admission and discharge data were analyzed. A Kidney Disease: Improving Global Outcomes-based SQL algorithm applied specific diagnosis-based International Classification of Diseases (ICD) codes to inpatient stays. Text mining on discharge documentation was also conducted to measure the effects on diagnosis.
RESULTS
We show that this approach yielded an increased number of diagnoses (4491 cases in 2014 vs 11,124 cases of ICD-coded kidney disease and injury in 2019) and higher precision in documentation and coding. The percentage of unspecific ICD N19-coded diagnoses of N19 codes generated dropped from 19.71% (1544/7833) in 2016 to 4.38% (416/9501) in 2019. The percentage of specific ICD N18-coded diagnoses of N19 codes generated increased from 50.1% (3924/7833) in 2016 to 62.04% (5894/9501) in 2019.
CONCLUSIONS
Our data-driven method supports the process and reliability of diagnosis and staging and improves the quality of documentation and data. Measuring patient outcomes will be the next step in this project
Determining Young’s modulus of coatings in vibrating reed experiments using irregularly shaped specimens
Knowing Young’s modulus of coatings is important to understand the stress evolution and failure of coating
systems. However, such values are often not available for modern coatings and/or cannot be determined by
existing methods for attaining a global stiffness. In this paper, a new method is described and validated that can be
used even for brittle, highly porous, and irregularly shaped coatings, for example sputtered or thermally sprayed
thermal barrier coatings: In vibrating reed experiments, the resonance frequencies of the specimens are determined.
The specimen geometry is measured by a computer tomograph, and a finite element simulation based on
that measured geometry is carried out to determine Young’s modulus. To validate this method, a monocrystalline
irregularly shaped silicon plate with known Young’s modulus was measured. The method is tested on different
metallic thermal spray coatings, for which other mechanical test methods for Young’s modulus were also
applicable for comparison. Lastly, a very porous, gas flow sputtered zirconia thermal barrier coating was analyzed
where other methods were not suitable
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