Gutenberg Open Science (Univ. Mainz)
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A stochastic field theory for the evolution of quantitative traits in finite populations
Get PDFInfinitely many distinct trait values may arise in populations bearing quantitative traits, and modeling their population dynamics is thus a formidable task. While classical models assume fixed or infinite population size, models in which the total population size fluctuates due to demographic noise in births and deaths can behave qualitatively differently from constant or infinite population models due to density-dependent dynamics. In this paper, I present a stochastic field theory for the eco-evolutionary dynamics of finite populations bearing one-dimensional quantitative traits. I derive stochastic field equations that describe the evolution of population densities, trait frequencies, and the mean value of any trait in the population. These equations recover wellknown results such as the replicator-mutator equation, Price equation, and gradient dynamics in the infinite
population limit. For finite populations, the equations describe the intricate interplay between natural selection, noise-induced selection, eco-evolutionary feedback, and neutral genetic drift in determining evolutionary trajectories. My work uses ideas from statistical physics, calculus of variations, and SPDEs, providing alternative methods that complement the measure-theoretic martingale approach that is more common in the literature
Children reinventing cinema : snapshots from the early 21st century
Get PDFChildren today discover a new digital drawing tool, the camera-crayon, at a very young age. They appropriate devices such as compact cameras and mobile phones and make their own media artifacts in their play. Expanding on a media-archaeological approach to film history, this book maps children’s playful and imaginative knowledge of contemporary media culture and explores their filmmaking practices that push the boundaries of forms and formats.205 Seite
Oscillometric, greyscale- and novel color-Doppler-ultrasound indices of macrovascular damage in Sjögren’s : the SICARD cohort study
Get PDFBackground
To assess for the first time a combination of oscillometric, greyscale- and novel color-Doppler ultrasound (US) indices of carotid and aortic damage in patients with primary Sjögren’s syndrome (pSS). Moreover, to examine associations of these markers with patient and disease-characteristics, as well as with a traditional cardiovascular (CV) risk score (SCORE) and its EULAR-modified version (mSCORE).
Methods
Greyscale and color-Doppler indices [resistance (RI)- and pulsatility (PI)-index], as well as markers of atherosclerosis [Intima-Media-Thickness (cIMT), plaques, and cumulative calcification surface], were examined in the common- (CCA) and internal- (ICA) carotid arteries of pSS patients and healthy controls. The gold standard oscillometric marker of aortic stiffness (carotid-femoral pulse wave velocity; cfPWV) and the traditional SCORE/mSCORE, were also assessed.
Results
We recruited 119 pSS-patients and 97 controls. Patients exhibited significantly higher cfPWV (padj = 0.025), cIMT (padj < 0.001), and calcification area (p = 0.013), compared to controls. According to mSCORE, 5.7% of the patients had high CV risk. However, cfPWV and carotid-sonography revealed increased aortic stiffness in 45.4% and carotid atherosclerosis in 69.2%, respectively. Among pSS-patients, cfPWV correlated with C-reactive-protein (rho = 0.325, p < 0.001), erythrocyte-sedimentation-rate (rho = 0.271, p = 0.003), and traditional CV-risk factors (age, cholesterol, systolic blood pressure: all; p < 0.01). ICA-RI and ICA-PI were higher in patients with further (non-rheumatological) autoimmune diseases (both; p < 0.05).
Conclusion
In the largest cfPWV/US-cohort examined to date, pSS-patients had significantly higher aortic stiffness and atherosclerosis than controls. Aortic stiffness was predicted by systemic inflammation, alongside traditional CV risk factors. cfPWV and carotid-US may help identify subclinical end-organ disease and atherosclerosis and thus assist CV/CVB-screening in pSS.
Trial registration
DRKS00031470
Balancing ethics and statistics : machine learning facilitates highly accurate classification of mice according to their trait anxiety with reduced sample sizes
Get PDFUnderstanding how individual differences influence vulnerability to disease and responses to pharmacological treatments represents one of the main challenges in behavioral neuroscience. Nevertheless, inter-individual variability and sex-specific patterns have been long disregarded in preclinical studies of anxiety and stress disorders. Recently, we established a model of trait anxiety that leverages the heterogeneity of freezing responses following auditory aversive conditioning to cluster female and male mice into sustained and phasic endophenotypes. However, unsupervised clustering required larger sample sizes for robust results which is contradictory to animal welfare principles. Here, we pooled data from 470 animals to train and validate supervised machine learning (ML) models for classifying mice into sustained and phasic responders in a sex-specific manner. We observed high accuracy and generalizability of our predictive models to independent animal batches. In contrast to data-driven clustering, the performance of ML classifiers remained unaffected by sample size and modifications to the conditioning protocol. Therefore, ML-assisted techniques not only enhance robustness and replicability of behavioral phenotyping results but also promote the principle of reducing animal numbers in future studies
Effizienz und Sicherheit der sonographisch-gestützten zentralvenösen Katheteranlage in der Kinderchirurgie unter Einsatz eines Head-Mounted Displays – eine randomisierte, kontrollierte Studie
Get PDFIII, 57 Seiten ; Illustratione
A manganese(I) complex with a 190 ns metal-to-ligand charge transfer lifetime
Get PDFApplication of photoactive transition metal complexes in lighting, imaging, sensing, and photocatalysis is usually based on the triplet metal-to-ligand charge transfer (3MLCT) excited state of precious metal complexes with 4/5d6 valence electron configurations. These photocatalysts exhibit excited state lifetimes exceeding hundreds of nanoseconds. Simple 3d6 transition metal complexes containing abundant metals exhibit lifetimes below 1–2 nanoseconds, and they require multistep ligand syntheses mitigating large-scale implementation. We report that a commercially available bis(imidazolium) pyridine pro-ligand [H2pbmi]2+ and a manganese(II) salt yield the tetracarbene manganese(I) complex [Mn(pbmi)2]+. This complex phosphoresces at room temperature in fluid solution from a 3MLCT state with a lifetime of 190 ns. In combination with the reversible [Mn(pbmi)2]2+/+ process, this translates to an excited state capable of reducing benzophenone. Combination of manganese(I) with rigid carbene/pyridine ligands expands key strategies for photoactive 3d6 metal complexes of earth-abundant metals with 3MLCT lifetimes rivalling those of precious metals and providing a conceptual starting point for a sustainable photochemistry
Utilizing information communication technologies (ICTs) during the process of disaffiliating from the ultra-Orthodox community
Get PDFThe ultra-Orthodox community is characterized by high levels of commitment to community and religion and insulation from the outside world. Leaving such a community resembles the process of migration, in which the individual encounters new cultures, norms, and behaviors. This presents challenges with integration and disaffiliated community members do indeed often lack the tools, skills, and knowledge to successfully integrate into their new societies. Through qualitative in-depth interviews, we examine the role of information communication technologies (ICTs) and media in the processes of disaffiliation from ultra-Orthodox communities. Findings reveal the enablers and constraints these individuals experience in their journey and shed light on the importance of media and ICTs in individuals’ attempts to build new lives outside the ultra-Orthodox community. This study contributes to a better understanding of the role of media and ICTs in the lives of people undergoing major life changes, such as disaffiliation from the ultra-Orthodox community
Beschreibung der ersten deutschen Familie mit Chondrokalzinose (CCAL1) mit molekulargenetisch nachgewiesener TNFRSF11B-Genmutation
Get PDF77 Seiten ; Illustrationen, Diagramm
Prophylactic endoscopic pylorus dilatation prior to esophagectomy for esophageal cancer to prevent delayed gastric emptying, study protocol for a placebo-controlled randomized trial (PROPPER trial)
Get PDFIntroduction
Delayed gastric emptying (DGE) due to pyloric dysfunction remains a common postoperative complication after esophagectomy for cancer and can lead to severe secondary complications. As shown in a retrospective study, prophylactic EPBD performed 1 day before surgery can reduce the rate of postoperative DGE by reducing pyloric resistance.
The objective of this study is to analyze the effect of prophylactic EPBD on postoperative DGE rates in patients receiving minimally invasive esophagectomy for cancer by gastric pull-up.
Methods
This study is designed as a multicenter randomized controlled trial (RCT) including patients with esophageal cancer or cancer of the gastroesophageal junction (adenocarcinoma and squamous cell carcinoma, with or without neoadjuvant treatment) scheduled for minimally invasive esophagectomy with gastric pull-up. After randomization, patients will either receive preoperative EPBD or a sham intervention in the routine preoperative endoscopy performed 1 day before surgery. The primary endpoint of this study will be rates of DGE, particularly those resulting from pyloric dysfunction, requiring intervention. Secondary outcomes will be major and minor postoperative complication rates, in-hospital mortality, adverse events during gastroscopy, length of ICU and hospital stay as well as postoperative pain and quality of life. In order to detect a difference between both groups at a two-sided 5% significance level, to achieve a power of 0.8 with a calculated dropout rate of approximately 20%, a sample size of 118 patients with 59 patients in every study arm will be needed.
Discussion
The presented PROPPER trial is the first multicenter RCT that will provide evidence regarding the efficacy of preoperative EPBD in reducing DGE after minimally invasive esophagectomy for cancer.
Trial registration
This trial was registered in the German Clinical Trials Register (DRKS), under the identifier DRKS00034360. Registered on May 29, 2024.
The WHO trial registration data set can be found here: http://drks.de/search/en/trial/DRKS00034360