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Air-liquid interface cultures trigger a metabolic shift in intestinal epithelial cells (IPEC‑1)
No full textAn improved oxygen availability in air–liquid interface (ALI) cultures of enterocytes of the small intestine seems to be
primarily responsible for morphological, metabolic, and functional changes. Intestinal porcine epithelial cells 1 (IPEC-1)
are less investigated and are rarely used as model for intestinal barrier but showed a profound change of cell shape during
ALI cultivation. We aim to answer the following question: Are the observed morphological effects accompanied by changes
in metabolic function? A microarray analysis of submerged culture (SMC) and ALI cultures identified 830 significantly
regulated genes. Subsequent functional clustering revealed alterations in 31 pathways, with the highest number of regulated
genes in metabolic pathways, carbon metabolism, glycolysis, and hypoxia-inducible factor (HIF) signaling. Furthermore,
HIF-1α as a mediator of a metabolic switch between glycolysis and oxidative phosphorylation showed a trend of increased
mRNA levels in ALI in contrast to a reduced nuclear HIF-1α content in the nucleus. Candidate genes of oxidative phospho-
rylation such as a mitochondrial marker exhibited enhanced mRNA levels, which was confirmed by western blot analysis.
Cytochrome C oxidase (COX) subunit 5B protein was decreased in ALI, although mRNA level was increased. The oxidation
of ferrocytochrome C to ferricytochrome C was used for detection of cytochrome C oxidase activity of isolated mitochondria
and resulted in a trend of higher activity in ALI. Furthermore, quantification of glucose and lactate concentrations in cell
culture medium revealed significantly reduced glucose levels and decreased lactate production in ALI. To evaluate energy
metabolism, we measured cellular adenosine triphosphate (ATP) aggregation in homogenized cell suspensions showing
similar levels. However, application of the uncoupling agent FCCP reduced ATP levels in ALI but not in SMC. In contrast,
blocking with 2-desoxy-d-glucose (2DG) significantly reduced ATP content in ALI and SMC. These results indicate a
metabolic shift in IPEC-1 cultured under ALI conditions enhancing oxidative phosphorylation and suppressing glycolysis
Apicomplexan parasites are attenuated by low‑energy electron irradiation in an automated microfluidic system and protect against infection with Toxoplasma gondii
No full textModel of Inspiring Media
No full textScholars have increasingly explored the ways that media content can touch, move, and inspire audiences, leading to numerous
beneficial outcomes including increased feelings of connectedness to and heightened motivations for doing good for others. Although this line
of inquiry is relatively new, sufficient evidence and patterns of results have emerged such that a clearer picture of the inspiring media
experience is coming into focus. This article has two primary goals. First, we seek to synthesize the existing research into a working and
evolving model of inspiring media experiences reflecting five interrelated and symbiotic elements: exposure, message factors, responses,
outcomes, and personal/situational factors. The model also identifies theoretical mechanisms underlying the previously observed positive
effects. Secondly, the article explores situations in which, and precipitating factors present, when these hoped-for outcomes either fail to
materialize or result in negative or maladaptive responses and outcomes. Ultimately, the model is proposed as a heuristic roadmap for future
scholarship and as an invitation for critique and collaboration in the emerging field of positive media psychology
Jugendliche als Täter:innen und Opfer von abweichendem Verhalten im digitalen Raum
No full textDer digitale Raum ist zu einem zentralen Bestandteil der Lebenswelt von Jugendlichen geworden. Insbesondere digitale Kommunikationsformen sind fest in den Alltag integriert, sodass für viele Jugendliche kaum noch eine Trennung zwischen digitaler und analoger Welt besteht. Neben neuen Möglichkeiten der Interaktion eröffnet der digitale Raum jedoch auch neue Kontexte für abweichendes und delinquentes Verhalten. Während deviantes Verhalten im Jugendalter grundsätzlich als entwicklungsbedingt gelten kann, ist bislang unzureichend erforscht, inwieweit sich jugendtypische abweichende Verhaltensweisen in den digitalen Raum ausweiten oder dort eigenständige Formen annehmen. Die vorliegende kumulative Dissertation untersucht anhand vier Einzelbeiträge cyberdeviante Verhaltensweisen von Jugendlichen mit analogen Entsprechungen, insbesondere Cyberbullying, Cyberstalking und Cybergrooming. Ziel ist es, erstens die Prävalenz von Täter:innen- und Opfererfahrungen im digitalen Raum zu bestimmen und zweitens den Einfluss von Faktoren aus dem analogen und digitalen Kontext auf diese Verhaltensweisen zu analysieren. Dabei wird geprüft, ob cyberdeviante Verhaltensweisen primär als Erweiterung analoger Devianz zu verstehen sind oder eigenständige Charakteristika aufweisen. Die empirische Basis bilden vier repräsentative Schüler:innenbefragungen der neunten Jahrgangsstufe, die in den Jahren 2013 bis 2017 in Niedersachsen sowie einer westdeutschen Großstadt durchgeführt wurden. Die Analysen beruhen auf Dunkelfeldbefragungen und nutzen unter anderem binär logistische Mehrebenen-Regressionen sowie multiple Mediationsmodelle. Theoretisch greift die Arbeit unter anderem auf die General Strain Theory sowie die Theorie der Selbstkontrolle bzw. des riskanten Lebensstils zurück. Die Ergebnisse zeigen, dass cyberdeviantes Verhalten unter Jugendlichen in relevantem Umfang verbreitet ist. Während wiederholte Cyberbullying-Täter:innenschaft nur einen kleinen Anteil betrifft, berichten deutlich mehr Jugendliche von aggressivem Verhalten im digitalen Raum sowie von Cyberstalking- und Cybergrooming-Erfahrungen. Die Befunde schließen eine Forschungslücke, da sie auf repräsentativen Stichproben beruhen und verlässliche Prävalenzschätzungen für Deutschland ermöglichen. Zugleich zeigen die Analysen deutliche Überschneidungen zwischen analogem und digitalem abweichendem Verhalten. Cyberbullying und Cyberstalking treten häufig in beiden Kontexten gemeinsam auf, was dafür spricht, dass cyberdeviante Verhaltensweisen vielfach eine Erweiterung bestehender analoger Muster darstellen. Gleichzeitig existieren auch rein digitale Ausprägungen. Hinsichtlich der Einflussfaktoren zeigt sich, dass Täter:innen- und Opfererfahrungen sowohl mit individuellen, familiären, schulischen und peerbezogenen Faktoren als auch mit spezifischen Risikofaktoren aus dem digitalen Raum assoziiert sind. Insgesamt verdeutlichen die Ergebnisse, dass der digitale Raum einen weiteren zentralen Kontext für jugendtypisches deviantes Verhalten darstellt. Klassische kriminologische Theorien erweisen sich grundsätzlich als geeignet zur Erklärung cyberdevianter Verhaltensweisen, müssen jedoch um digitale Kontextfaktoren ergänzt werden. Die Arbeit unterstreicht die enge Verwobenheit von Online- und Offline-Welt im Jugendalter und liefert wichtige Implikationen für Forschung und Prävention
Amplified photomodulation of a bis(dithienylethene)-substituted phosphine
No full textPhosphine ligands play a crucial role in homogeneous catalysis, allowing fine-tuning of the catalytic activity of various metals by modifying their structure. An ultimate challenge in this field is to reach controlled modulation of catalysis in situ, for which the development of phosphines capable of photoswitching between states with differential electronic properties has been proposed. To magnify this light-induced behavior, in this work we describe a novel phosphine ligand incorporating two dithienylethene photoswitchable moieties tethered to the same phosphorus atom. Double photoisomerization was observed for this ligand, which remains unhindered upon gold(I) complexation. As a result, the preparation of a fully ring-closed phosphine isomer was accomplished, for which amplified variation of phosphorus electron density was verified both experimentally and by computational calculations. Accordingly, the presented molecular design based on multiphotochromic phosphines could open new ways for preparing enhanced photoswitchable catalytic systems
Assessment of the Relationship between Periodontitis and Cardiac Parameters in Patients with Early Chronic Heart Failure: A Cross-Sectional Study
No full textPeriodontal disease (PD) is considered a risk factor for cardiovascular events. However, its relationship to chronic heart failure (CHF) is unclear. The aim was to compare cardiac and inflammatory parameters in CHF patients with (PG) versus without periodontitis (NPG). The following parameters were recorded in 58 patients: periodontal screening and recording (PSR), troponin T, NT-proBNP, C-reactive protein (CRP), interleukin-6 (IL-6), blood pressure, heart rate, ejection fraction (EF), ventricular systolic and diastolic function parameters, incremental test, and three questionnaires (Mediterranean Diet Adherence Screener, MEDAS; Oral Health Impact Profile, OHIP-14; Patient Health Questionnaire, PHQ). The serum levels of NT-proBNP and troponin T were significantly higher in the PG, and the left ventricular systolic and diastolic function parameters were significantly lower. The correlation analysis showed age as the only independent risk factor for periodontitis and cardiac biomarkers. No significant group differences were found in the MEDAS, OHIP-14, and PHQ scores, or in CRP, IL-6, and cardiocirculatory parameters. Overall, the BMI correlated significantly with the mean PSR and total cholesterol. The occurrence of increased PSR together with increased age and cardiac risk parameters does not exclude an association between periodontitis and CHF, though no positive correlation was calculated. Periodontitis may be a modifiable risk factor for CHF. Its treatment may help to control the inflammatory burden
Changes in the Red Sea overturning circulation during Marine Isotope Stage 3
No full textThe oceanography of the Red Sea is controlled by the restricted exchange of water masses with the Indian Ocean and by high evaporation rates due to the arid climate of the surrounding land areas. In the northern Red Sea, the formation of oxygen-rich subsurface water ventilates the deeper parts of the basin, but little is known about the variability in this process in the past. The stable oxygen and carbon isotope records of epibenthic foraminifera from a sediment core of the central Red Sea and comparison with existing isotope records allow for the reconstruction of changes in the Red Sea overturning circulation (ROC) during Marine Isotope Stage 3. The isotope records imply millennial-scale variations in the ROC, in phase with the climate variability in the high northern latitudes. This suggests an immediate response of dense-water formation to the regional climate and hydrology of the northern Red Sea. Deep-water formation was intensified under the influence of cold and hyper-arid conditions during Heinrich stadials and was diminished during Dansgaard–Oeschger interstadials. While these changes are reflected in both stable oxygen and carbon isotope records, the latter data also exhibit changes in phase with the African–Indian monsoon system. The decoupling of the stable carbon and oxygen isotope records at the summer monsoon maximum centered around 55–60 ka may be associated with an increased inflow of nutrient-rich intermediate waters from the Arabian Sea to the central Red Sea. This process fueled local surface water productivity, resulting in enhanced remineralization of sinking organic matter and release of 12C at intermediate water depths
Decoding energy decomposition analysis: Machine-learned Insights on the impact of the density functional on the bonding analysis
No full textThe concept of chemical bonding is a crucial aspect of chemistry that aids in under-
standing the complexity and reactivity of molecules and materials. However, the
interpretation of chemical bonds can be hindered by the choice of the theoretical
approach and the specific method utilized. This study aims to investigate the effect
of choosing different density functionals on the interpretation of bonding achieved
through energy decomposition analysis (EDA). To achieve this goal, a data set was
created, representing four bonding groups and various combinations of functionals
and dispersion correction schemes. The calculations showed significant variation
among the different functionals for the EDA terms, with the dispersion correction
terms exhibiting the highest variability. More information was extracted by using
machine learning in combination with dimensionality reduction on the data set.
Results indicate that, despite the differences in the EDA terms obtained from differ-
ent functionals, the functional has the least significant impact, suggesting minimal
influence on the bonding interpretation
Decreased long-range temporal correlations in the resting- state functional magnetic resonance imaging blood-oxygen- level-dependent signal reflect motor sequence learning up to 2 weeks following training
No full textDecreased long-range temporal correlations (LRTC) in brain signals can be used to measure cognitive effort during task execution. Here, we examined how learning a motor sequence affects long-range temporal memory within resting-state functional magnetic resonance imaging signal. Using the Hurst exponent (HE), we estimated voxel-wise LRTC and assessed changes over 5 consecutive days of training, followed by a retention scan 12 days later. The experimental group learned a complex visuomotor sequence while a complementary control group performed tightly matched movements. An interaction analysis revealed that HE decreases were specific to the complex sequence and occurred in well-known motor sequence learning associated regions including left supplementary motor area, left premotor cortex, left M1, left pars opercularis, bilateral thalamus, and right striatum. Five regions exhibited moderate to strong negative correlations with overall behavioral performance improvements. Following learning, HE values returned to pretraining levels in some regions, whereas in others, they remained decreased even 2 weeks after training. Our study presents new evidence of HE's possible relevance for functional plasticity during the resting-state and suggests that a cortical subset of sequence-specific regions may continue to represent a functional signature of learning reflected in decreased long-range temporal dependence after a period of inactivity