Perspectives of measuring gravitational effects of laser light and particle beams

We study possibilities of creation and detection of oscillating gravitational fields from lab-scale high energy, relativistic sources. The sources considered are high energy laser beams in an optical cavity and the ultra-relativistic proton bunches circulating in the beam of the Large Hadron Collider (LHC) at CERN. These sources allow for signal frequencies much higher and far narrower in bandwidth than what most celestial sources produce. In addition, by modulating the beams, one can adjust the source frequency over a very broad range, from Hz to GHz. The gravitational field of these sources and responses of a variety of detectors are analyzed. We optimize a mechanical oscillator such as a pendulum or torsion balance as detector and find parameter regimes such that -- combined with the planned high-luminosity upgrade of the LHC as a source -- a signal-to-noise ratio substantially larger than 1 should be achievable at least in principle, neglecting all sources of technical noise. This opens new perspectives of studying general relativistic effects and possibly quantum-gravitational effects with ultra-relativistic, well-controlled terrestrial sources.Comment: Main Text: 25 pages, 1 figure. Appendix: 7 pages, 2 figure

Funktionelle Charakterisierung der humanen Proteinkinase Aurora-C in Krebszellen

Aurora-Kinasen sind eine konservierte Familie von Serin/Threonin-Kinasen, die an der Regulation der Mitose und Meiose in eukaryotischen Organismen beteiligt sind. Die Aurora-Subfamilie in Säugern besteht aus drei Kinasen, die Aurora-A, -B und -C bezeichnet werden. Im Gegensatz zu Aurora-A und -B sind die physiologischen Funktionen der Kinase Aurora-C unbekannt. Aurora-Kinasen vom Typ C konnten bisher nur in Säugerzellen nachgewiesen werden. Die Expression der Kinase scheint sich dabei auf die männlichen und weiblichen Keimdrüsen sowie bestimmte Krebszelllinien und Tumoren zu beschränken. Das Ziel dieser Arbeit war die Charakterisierung der humanen Proteinkinase Aurora-C in Krebszellen. Die Untersuchung verschiedener Aurora-C-Derivate im Rahmen dieser Arbeit hat gezeigt, dass die Mutante Aurora-C-T191D im Vergleich zu anderen Aurora-C-Derivaten (WT, K72R T198D, T202D) eine erhöhte Kinaseaktivität in vitro aufweist und als hyperaktiv bezeichnet werden kann. Die proteinchemische Untersuchung der hyperaktiven Mutante Aurora-C-T191D hat außerdem ergeben, dass das überexprimierte Protein in HeLa-Zellen posttranslational modifiziert wird. Die physiologischen Auswirkungen dieser Modifikation sind allerdings unbekannt. Die weiteren Untersuchungen im Rahmen dieser Arbeit haben gezeigt, dass der Kinase Aurora-C eine Funktion bei der Regulation der Zellmorphologie in Epithelzellen zukommt. Die Behandlung von HeLa-Zellen mit shRNAs gegen Aurora-C und die Überexpression der hyperaktiven Mutante Aurora-C-T191D in HeLa-Zellen bewirken den Verlust des cytoplasmatischen Raums und der Zellpolarität in den betroffenen Zellen. Ein weiterer Schwerpunkt im Rahmen dieser Arbeit bildete die Identifizierung von Interaktionspartnern der Kinase Aurora-C durch einen Two-Hybrid-Screen in der Hefe Saccharomyces cerevisiae. Unter anderem wurden drei Proteine (Calpain-4, Epiplakin, Interleukin 15) identifiziert, die wie Aurora-C eine Veränderung der Zellmorphologie bewirken können. Im Rahmen dieser Arbeit wurde von den drei Proteinen allerdings nur Calpain-4 näher unter-sucht. Es konnte gezeigt werden, dass Calpain-4 in vitro kein Substrat der Kinase Aurora-C ist und dass die beiden Proteine nach Überexpression spezifisch im Zellkern, an der postmitotischen Brücke und am Zellrand kolokalisieren. Ein weiteres Protein, das im Two-Hybrid-Screen identifiziert wurde, ist das Telomerbindeprotein TRF2. Im Rahmen dieser Arbeit konnte gezeigt werden, dass die Kinase Aurora-C das Substrat TRF2 in vitro an der Position Threonin 358 spezifisch phosphorylieren kann

Organic matter modeling at the landscape scale based on multitemporal soil pattern analysis using RapidEye data

This study proposes the development of a landscape-scale multitemporal soil pattern analysis (MSPA) method for organic matter (OM) estimation using RapidEye time series data analysis and GIS spatial data modeling, which is based on the methodology of Blasch et al. The results demonstrate (i) the potential of MSPA to predict OM for single fields and field composites with varying geomorphological, topographical, and pedological backgrounds and (ii) the method conversion of MSPA from the field scale to the multi-field landscape scale. For single fields, as well as for field composites, significant correlations between OM and the soil pattern detecting first standardized principal components were found. Thus, high-quality functional OM soil maps could be produced after excluding temporal effects by applying modified MSPA analysis steps. A regional OM prediction model was developed using four representative calibration test sites. The MSPA-method conversion was realized applying the transformation parameters of the soil-pattern detection algorithm used at the four calibration test sites and the developed regional prediction model to a multi-field, multitemporal, bare soil image mosaic of all agrarian fields of the Demmin study area in Northeast Germany. Results modeled at the landscape scale were validated at an independent test site with a resulting prediction error of 1.4 OM-% for the main OM value range of the Demmin study area

Big Five Personality Traits Predict Successful Transitions From School to Vocational Education and Training: A Large-Scale Study

Educational transitions play a pivotal role in shaping educational careers, and ultimately social inequality. Whereas parental socioeconomic status (SES) and cognitive ability have long been identified as key determinants of successful educational transitions, much less is known about the role of socio-emotional skills. To address this gap, the present study investigated whether Big Five personality traits predict success in the transition from secondary school to vocational education and training (VET) above and beyond SES, cognitive ability, and other covariates. Using data from Starting Cohort 4 of the German National Educational Panel Study (NEPS; N = 4,137), we defined seven indicators of successful transition: obtaining a VET position, number of acceptances for VET positions, starting a VET position, (the absence of) dropout intentions and actual dropout, final VET grade, and satisfaction with VET. The results revealed that some Big Five traits were incrementally associated with several indicators of transition success. Conscientiousness emerged as the single most relevant trait, predicting all the transition success indicators but 1 (dropout intentions). The other Big Five traits had much weaker and less consistent links with transition success. Extraversion predicted the final VET grade and obtaining a VET position; Agreeableness was linked to a higher risk of dropout. Openness and Emotional Stability had no incremental effects on transition success. There was also some evidence for both compensatory and synergistic interactive effects, with Openness moderating mainly the effects of parental SES (on dropout intentions, actual dropout, and number of acceptances), and Agreeableness moderating the effects of cognitive ability (on obtaining a VET position, number of acceptances, and satisfaction with VET). Although individual effect sizes were small, the Big Five’s joint contribution to transition success was non-negligible, and often larger than that of sociodemographic characteristics and cognitive ability. Our results suggest a hitherto underappreciated contribution of personality to successful transitions to VET

Influence of cosmological expansion in local experiments

Whether the cosmological expansion can influence the local dynamics, below the galaxy clusters scale, has been the subject of intense investigations in the past three decades. In this work, we consider McVittie and Kottler spacetimes, embedding a spherical object in a FLRW spacetime. We calculate the influence of the cosmological expansion on the frequency shift of a resonator and estimate its effect on the exchange of light signals between local observers. In passing, we also clarify some of the statements made in the literature.Marie Sklodowska-Curie Actionshttps://doi.org/10.13039/100018694Deutsche Forschungsgemeinschafthttps://doi.org/10.13039/501100001659Alexander von Humboldt-Stiftunghttps://doi.org/10.13039/100005156Peer Reviewe

Imprinted Zac1 in neural stem cells.

Neural stem cells (NSCs) and imprinted genes play an important role in brain development. On historical grounds, these two determinants have been largely studied independently of each other. Recent evidence suggests, however, that NSCs can reset select genomic imprints to prevent precocious depletion of the stem cell reservoir. Moreover, imprinted genes like the transcriptional regulator Zac1 can fine tune neuronal vs astroglial differentiation of NSCs. Zac1 binds in a sequence-specific manner to pro-neuronal and imprinted genes to confer transcriptional regulation and furthermore coregulates members of the p53-family in NSCs. At the genome scale, Zac1 is a central hub of an imprinted gene network comprising genes with an important role for NSC quiescence, proliferation and differentiation. Overall, transcriptional, epigenomic, and genomic mechanisms seem to coordinate the functional relationships of NSCs and imprinted genes from development to maturation, and possibly aging

Analyzing Temporal and Spatial Characteristics of Crop Parameters Using Sentinel-1 Backscatter Data

The knowledge about heterogeneity on agricultural fields is essential for a sustainable and effective field management. This study investigates the performance of Synthetic Aperture Radar (SAR) data of the Sentinel-1 satellites to detect variability between and within agricultural fields in two test sites in Germany. For this purpose, the temporal profiles of the SAR backscatter in VH and VV polarization as well as their ratio VH/VV of multiple wheat and barley fields are illustrated and interpreted considering differences between acquisition settings, years, crop types and fields. Within-field variability is examined by comparing the SAR backscatter with several crop parameters measured at multiple points in 2017 and 2018. Structural changes, particularly before and after heading, as well as moisture and crop cover differences are expressed in the backscatter development. Furthermore, the crop parameters wet and dry biomass, absolute and relative vegetation water content, leaf area index (LAI) and plant height are related to SAR backscatter parameters using linear and exponential as well as multiple regression. The regression performance is evaluated using the coefficient of determination (R 2 ) and the root mean square error (RMSE) and is strongly dependent on the phenological growth stage. Wheat shows R 2 values around 0.7 for VV backscatter and multiple regression and most crop parameters before heading. Single fields even reach R 2 values above 0.9 for VV backscatter and for multiple regression related to plant height with RMSE values around 10 cm. The formulation of clear rules remains challenging, as there are multiple influencing factors and uncertainties and a lack of conformity.BMEL, 2815710715, Verbundprojekt: Erzeugung von landwirtschaftlichen Ertragspotenzialkarten durch Fusion von Ertragskartierungen, Fernerkundungsdaten, digitaler Reliefauswer-tung und Bewirtschaftungsdaten (AgriFusion) - Teilprojekt

Exploring the Monoterpene Indole Alkaloid Scaffold for Reversing P-Glycoprotein-Mediated Multidrug Resistance in Cancer

Dregamine (1), a major monoterpene indole alkaloid isolated from Tabernaemontana elegans, was submitted to chemical transformation of the ketone function, yielding 19 azines (3-21) and 11 semicarbazones (22-32) bearing aliphatic or aromatic substituents. Their structures were assigned mainly by 1D and 2D NMR (COSY, HMQC, and HMBC) experiments. Compounds 3-32 were evaluated as multidrug resistance (MDR) reversers through functional and chemosensitivity assays in a human ABCB1-transfected mouse T-lymphoma cell model, overexpressing P-glycoprotein. A significant increase of P-gp inhibitory activity was observed for most derivatives, mainly those containing azine moieties with aromatic substituents. Compounds with trimethoxyphenyl (17) or naphthyl motifs (18, 19) were among the most active, exhibiting strong inhibition at 0.2 mu M. Moreover, most of the derivatives showed selective antiproliferative effects toward resistant cells, having a collateral sensitivity effect. In drug combination assays, all compounds showed to interact synergistically with doxorubicin. Selected compounds (12, 17, 18, 20, and 29) were evaluated in the ATPase activity assay, in which all compounds but 12 behaved as inhibitors. To gather further insights on drug-receptor interactions, in silico studies were also addressed. A QSAR model allowed us to deduce that compounds bearing bulky and lipophilic substituents were stronger P-gp inhibitors