A general synthetic strategy and biological activity of B1-Phytoprostanes

During the last century, researchers have focused on the influence of certain chemicals involved in interactions between living organisms. The production or biosynthesis of such organic compounds and their distribution between the producers or between other organisms are important questions in chemical ecology. The response to signalling molecules, the effects of certain toxins and especially the interactions between different kingdoms, such as insect-plant interactions, fungi-plant nteractions or plant-plant interactions, represent major research topics of this field. Over their entire lifetime, plants are exposed to a variety of stress factors. Such stress factors can be either abiotic or biotic. Abiotic stress is caused by environmental factors, such as water deficit, extreme temperature or light conditions. Biotic stress is caused by different living organisms, such as herbivores, pathogens or fungi. Stress affects plants in their development and reproduction processes. Since they are unable to move, they have evolved efficient strategies to cope with or to adapt to such stresses. Plants have developed a wide range of defensive mechanisms to survive and fight against attacking enemies. Recognition of enemies and the triggered answer cascade is part of the study of chemical ecology as well

Heterochromatin composition, organization and MeCP2 post-translational modifications

In the cell nucleus, the DNA together with several other factors is packaged into chromatin which is organized into active and inactive compartments called euchromatin and heterochromatin. The maintenance of the silenced and compacted heterochromatin state is highly important for the genome stability and spatial organization of nuclear compartments and its misfunction can cause severe deficits in cellular processes. Heterochromatin is comprised of facultative heterochromatin that becomes active in specific situations and constitutive heterochromatin that is mostly silenced and constantly compacted. Constitutive heterochromatin from (peri)centromeric regions of several chromosomes fuses during interphase in mouse cells making up heterochromatin clusters. As the mechanism of the formation of constitutive heterochromatin and the factors involved in the process are not fully understood, we investigated the composition of constitutive heterochromatin in mouse tissues. Therefore, we optimized a protocol for native and unbiased isolation of heterochromatin clusters from mouse tissues and combined it with a quantitative mass spectrometry approach. We identified and validated previously unknown proteins along with proteins known to be involved in constitutive heterochromatin cluster formation and function. We observed differing heterochromatin organization between tissues and identified heterochromatin proteins with distinct abundance between mouse brain and liver tissue. Especially MeCP2, ATRX, and histone H1 might play a role in the distinct heterochromatin organization between tissues, but also newly identified candidate heterochromatin proteins could be involved. We found the methyl-CpG binding protein (MeCP2) enriched in the mouse brain. It binds to methylated cytosines on the DNA, recruits numerous chromatin-associated factors, and was shown to induce dose-dependent heterochromatin reorganization during terminal differentiation. Mutations in the MECP2 gene were associated with the neurological disorder Rett syndrome and altered protein levels were reported to cause disease phenotypes. Thus, we quantified MeCP2 levels in mouse brain nuclei and a cellular system upon exogenous expression of Mecp2-GFP. We showed that the level of MeCP2 in mouse brains is similar to its level in low transfected cells in our cellular system. In addition, we estimated the MeCP2 protein concentrations in the cell nucleus and heterochromatin compartments. We established a system that enables us to adjust the MeCP2 level of in cellulo and in vitro experiments to the in vivo protein level, thus ensuring comparability of experimental results to the physiological situation. Heterochromatin organization and its function are not only regulated by the proteins involved and their levels, but also by post-translational modifications of chromatin proteins. Hence, we isolated MeCP2 from the adult mouse brain and analyzed its modifications by mass spectrometry. We identified various post-translational modifications on MeCP2 and confirmed the influence of arginine methylation and to a lesser extent serine phosphorylation on MeCP2-mediated heterochromatin organization in a cellular system. Coexpression of arginine methyltransferases 1 and 6 lead to a decrease in heterochromatin clustering. Interestingly, we identified the Rett syndrome mutation R106 as a possible dimethylation site, implicating a role of MeCP2 post-translational modifications in the pathology of Rett syndrome. In summary, our data contribute to a better understanding of the constitutive heterochromatin organization in cells and its role in disease development

Ihmisarvon käsitteen moninaisuudesta : Ihmisarvon käsitteen hyödyntäminen keskustelussa munasolujen ennakoivasta pakastamisesta

Tämän tutkimuksen tehtävä on selvittää ihmisarvon käsitteen merkityksiä ja käsitteen käyttöön liittyviä haasteita muun muassa bioeettisissä keskusteluissa. Tutkimus esittelee mitä merkityksiä ihmisarvon käsite on saanut ja miten käsitteen merkitys on muuttunut ajan myötä. Analyysin kohteena ovat yleismaailmalliset ja alueelliset julistukset, jotka ovat muokanneet vahvasti modernin ihmisarvon käsitettä. Soveltavan luvun tarkoitus on lähestyä munasolujen ennakoivaa pakastamista ilmiönä ja soveltaa aiemmin työstetyn ihmisarvon käsitettä keskusteluun. Sen lisäksi tutkimuksen tarkoitus on toimia suomenkielisenä johdantona ihmisarvotutkimuksen laajaan kenttään ja esittää englanninkielisen ja saksankielisen ihmisarvotutkimuksen eroja ja yhtäläisyyksiä. Tutkimusmetodina on systemaattinen käsiteanalyysi, jonka tarkoituksena on kuvata, mitä käsitteellä ihmisarvo todellisuudessa tarkoitetaan. Käsiteanalyysi lähestyy ihmisarvon käsitteen ominaispiirteitä ja haasteita kriittisesti. Apuna toimii Anu Puusan artikkeli ”Käsiteanalyysin tutkimusmenetelmät”. Tutkimusaineiston valintaa ohjaa kirjallisuudentutkimuksesta lainattu dialogisuusteoria sekä intertekstuaalisuus, eli tekstien väliset kytkennät. Tutkimuksen kolmannessa luvussa esitän ihmisarvon käsitteen historiaa ja käsitteen muutoksen statukseen liittyvästä arvosta kaikille yhtäläisesti kuuluvaksi arvoksi. Sen lisäksi luku kolme esittelee millaisia merkityksiä ihmisarvolle on löydettävissä eri uskonnoissa ja millainen rooli ihmisarvon käsiteellä on kulttuurienvälisessä dialogissa. Tutkimuksen neljännessä luvussa analysoin, miten ihmisarvon käsite on käytetty yleismaailmallisissa ja alueellisissa julistuksissa ja miten julistuksien käyttämä ihmisarvon käsite on vaikuttanut myöhempien julistuksien ja perustuslakien ihmisarvon käsitteen käyttöön ja merkityksiin. Hyödynnän aiemmassa tutkimuksessa työstettyä ihmisarvon käsitteen kahtiajakoa ja tuon muita ihmisarvon käsitteeseen liittyviä merkityksiä esille. Tutkimuksen viides luku on tutkimuksen soveltava luku ja esittelee munasolujen ennakoivaa pakastamista ja ihmisarvon käsitteen merkityksiä munasolujen ennakoivaa pakastamista säätelevissä laissa. Viides luku esittelee menetelmään liittyvää keskustelua ja ihmisarvon käsitteen käyttöä keskustelussa

Finanzierung wissenschaftlicher Weiterbildung. Herausforderungen und Möglichkeiten bei der Implementierung und Umsetzung von weiterbildenden Angeboten an Hochschulen Thematischer Bericht der wissenschaftlichen Begleitung des Bundes-Länder-Wettbewerbs "Aufstieg durch Bildung: offene Hochschulen".

Die Finanzierung wissenschaftlicher Weiterbildung stellt aufgrund der besonderen Stellung der Weiterbildung an Hochschulen die damit befassten Akteure vor zentrale Herausforderungen. Deutlich zeigt sich hier der Widerspruch zwischen der Forderung Weiterbildung als Kernaufgabe an den Hochschulen zu etablieren und der gesonderten Finanzierungsmodelle, die aufgrund der notwendigen Kostendeckung über Gebühren entstehen. Die damit einhergehenden Herausforderungen werden in dem Thematischen Bericht auf Ebene der a) Trennungsrechnung, b) Vollkostenrechnung, c) Gebühren- und Entgeltberechnung und d) der Lehrendenvergütung skizziert, Umsetzungsmöglichkeiten dargelegt sowie Bundesländer übergreifende Lösungsansätze entwickelt. (DIPF/Orig.

Integrated policy package assessment (IPPA): A problem-oriented research approach for sustainability transformations

In this paper, we present the Integrated Policy Package Assessment (IPPA) approach and relate IPPA to three substantial concepts of problem-oriented research concerned with societal transformations: technology assessment (TA), sustainability research (SR), and responsible research and innovation (RRI). The IPPA approach provides (political) decision-makers with transformation and orientation knowledge via a four-step process of (1) design, (2) analysis, (3) evaluation, and (4) discourse of a policy package assessment. It is illustrated with a case study of urban passenger transport. As an integrated approach, IPPA has substantial ties to TA, SR, and RRI. It connects with TA in fundamental ways, since it combines the field of TA with the field of regulatory assessment based on consequence analysis. Connectable to the field of SR, IPPA addresses deliberation processes and sustainable pathway identification based on multi-criteria assessment. In addition, akin to the area of RRI, IPPA shows cross-cutting axes with regards to social resonance assessment and stakeholder evaluation with a focus on multi-actor responsibilities. In this contribution, we link evidence-based impact assessment with transformation pathway mechanisms and corresponding policy packages, backed by stakeholder-based responsible innovation feedback loops. This enhances the ex-ante analysis of policy packages regarding their intended as well as unintended consequences

Improving Robustness of Jet Tagging Algorithms with Adversarial Training

Deep learning is a standard tool in the field of high-energy physics, facilitating considerable sensitivity enhancements for numerous analysis strategies. In particular, in identification of physics objects, such as jet flavor tagging, complex neural network architectures play a major role. However, these methods are reliant on accurate simulations. Mismodeling can lead to non-negligible differences in performance in data that need to be measured and calibrated against. We investigate the classifier response to input data with injected mismodelings and probe the vulnerability of flavor tagging algorithms via application of adversarial attacks. Subsequently, we present an adversarial training strategy that mitigates the impact of such simulated attacks and improves the classifier robustness. We examine the relationship between performance and vulnerability and show that this method constitutes a promising approach to reduce the vulnerability to poor modeling.Comment: 17 pages, 16 figures, 2 tables. Replaced with the published version. Added the journal reference and the DOI. Code accessible under https://github.com/AnnikaStein/Adversarial-Training-for-Jet-Taggin

Approximating Fair kk-Min-Sum-Radii in Rd\mathbb{R}^d

The $k$-center problem is a classical clustering problem in which one is asked to find a partitioning of a point set $P$ into $k$ clusters such that the maximum radius of any cluster is minimized. It is well-studied. But what if we add up the radii of the clusters instead of only considering the cluster with maximum radius? This natural variant is called the $k$-min-sum-radii problem. It has become the subject of more and more interest in recent years, inspiring the development of approximation algorithms for the $k$-min-sum-radii problem in its plain version as well as in constrained settings. We study the problem for Euclidean spaces $\mathbb{R}^d$ of arbitrary dimension but assume the number $k$ of clusters to be constant. In this case, a PTAS for the problem is known (see Bandyapadhyay, Lochet and Saurabh, SoCG, 2023). Our aim is to extend the knowledge base for $k$-min-sum-radii to the domain of fair clustering. We study several group fairness constraints, such as the one introduced by Chierichetti et al. (NeurIPS, 2017). In this model, input points have an additional attribute (e.g., colors such as red and blue), and clusters have to preserve the ratio between different attribute values (e.g., have the same fraction of red and blue points as the ground set). Different variants of this general idea have been studied in the literature. To the best of our knowledge, no approximative results for the fair $k$-min-sum-radii problem are known, despite the immense amount of work on the related fair $k$-center problem. We propose a PTAS for the fair $k$-min-sum-radii problem in Euclidean spaces of arbitrary dimension for the case of constant $k$. To the best of our knowledge, this is the first PTAS for the problem. It works for different notions of group fairness

The Integrated Policy Package Assessment approach: elaborating ex ante knowledge in the feld of urban mobility

BACKGROUND: In response to climate change challenges, a main policy emphasis is on transitioning the energy system from high- to low-carbon energy supply. The German energy transition is first and foremost based on political decisions and interventions. These decisions need to be assessed ex ante to ensure a good governance approach to energy policies, for which this paper introduces the Integrated Policy Package Assessment approach (IPPA). IPPA consists of four steps: design, assessment, evaluation and discourse. RESULTS: The results section illustrates the IPPA framework by applying it to urban passenger transport as an example case. First, the design phase was used to elaborate two complementary policy packages each consisting of several policy measures in the transformation pathways of “multi- and inter-modality”, and “alternative drive”. Second, the individual measures of the packages were impact-analysed by a large number of individual impact studies from various disciplines. Synthesizing the individual study results, we developed an impact assessment matrix for impact evaluation. The matrix covers the impact categories: technology development, sector integration, environment, social resonance, and institutional factors. In a further step, the key findings of the impact assessment were reflected and reviewed from the perspectives of various stakeholders and practice experts through a practice–science dialogue on transforming the urban passenger transport system. CONCLUSIONS: The discussion and conclusion sections outline the main findings relating to content and process aspects, when applying the IPPA framework to a policy package in urban transport