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‘Smart’ Janus emulsions
(2021)
Emulsions constitute one of the most prominent and continuously evolving research areas in Colloid Chemistry, which involves the preparation of mixtures or dispersions of immiscible components in a continuous medium. Besides conventional oil-in-water or water-in-oil emulsions, other emulsions of complex droplet morphologies have recently attracted significant research interests. Especially Janus emulsions, in which each droplet is comprised of two distinct sub-regions, have shown versatile potential applications. One of their advantages is the possibility of compartmentalization, which enables to play with two different chemistries in a single droplet. Though microfluidic methods are conventionally used to prepare Janus emulsions, their industrial applications are largely hindered by low throughput and extensive instrumentations. Recently, it has been discovered that simply one-pot moderate/high energy emulsification is also capable of developing Janus morphology, although their preparation and stabilization remain rather substantially challenging. This cumulative doctoral thesis focuses on the preparation and characterization of ‘smart’ Janus emulsions, i.e. Janus emulsions with special stimuli-responsive features. One-step moderate/high energy emulsification of olive and silicone oil in an aqueous medium was carried out. Special consideration was devoted to the interfacial tensions among the components to maintain the criteria of forming characteristic droplet architectures, in addition to avoiding multiple emulsion destabilization phenomena like imminent phase separation or even separated droplet formation. A series of investigations were conducted related to the formation of complexes of charged macromolecules and role of them as stabilizers to achieve stable Janus emulsions for a realistic timeframe (more than 3 months). The correlation between the size of the stabilizer particles and the droplet size of emulsion was established. Furthermore, it was observed that Janus emulsion gels with interesting rheological properties can be fabricated in the presence of suitable polyelectrolyte complexes. Janus emulsions that could be influenced by pH, temperature or magnetic field were successfully produced in presence of characteristic stimuli-responsive stabilizers. Afterwards, the effect of these changes was studied by different characterization techniques. The size and morphology could be tuned easily by changing the pH. The incorporation of iron oxide magnetic nanoparticles (synthesized separately by a co-precipitation method) to one component of the Janus emulsion was carried out so that the movement and orientation of the complex droplets in aqueous media could be controlled by an external magnetic field. Additionally, temperature-triggered instantaneous reversible breakdown of Janus droplets was also accomplished. The responses of the Janus droplets by the stimuli were well-documented and explained. Another goal of the present contribution was to exploit this special morphological feature of emulsions as a template for producing porous materials. This was demonstrated by the preparation of ultralight magnetic responsive aerogels, utilizing Janus emulsion gels. The produced aerogels also showed the capacity to separate toxic dye from water. To the best of our knowledge, this is the first example of investigation towards batch scale production of Janus emulsion with such special stimuli-responsive properties by a simple bulk emulsification method.
The co-occurrence of warm spells and droughts can lead to detrimental socio-economic and ecological impacts, largely surpassing the impacts of either warm spells or droughts alone. We quantify changes in the number of compound warm spells and droughts from 1979 to 2018 in the Mediterranean Basin using the ERA5 data set. We analyse two types of compound events: 1) warm season compound events, which are extreme in absolute terms in the warm season from May to October and 2) year-round deseasonalised compound events, which are extreme in relative terms respective to the time of the year. The number of compound events increases significantly and especially warm spells are increasing strongly – with an annual growth rates of 3.9 (3.5) % for warm season (deseasonalised) compound events and 4.6 (4.4) % for warm spells –, whereas for droughts the change is more ambiguous depending on the applied definition. Therefore, the rise in the number of compound events is primarily driven by temperature changes and not the lack of precipitation. The months July and August show the highest increases in warm season compound events, whereas the highest increases of deseasonalised compound events occur in spring and early summer. This increase in deseasonalised compound events can potentially have a significant impact on the functioning of Mediterranean ecosystems as this is the peak phase of ecosystem productivity and a vital phenophase.
Compound weather events may lead to extreme impacts that can affect many aspects of society including agriculture. Identifying the underlying mechanisms that cause extreme impacts, such as crop failure, is of crucial importance to improve their understanding and forecasting. In this study, we investigate whether key meteorological drivers of extreme impacts can be identified using the least absolute shrinkage and selection operator (LASSO) in a model environment, a method that allows for automated variable selection and is able to handle collinearity between variables. As an example of an extreme impact, we investigate crop failure using annual wheat yield as simulated by the Agricultural Production Systems sIMulator (APSIM) crop model driven by 1600 years of daily weather data from a global climate model (EC-Earth) under present-day conditions for the Northern Hemisphere. We then apply LASSO logistic regression to determine which weather conditions during the growing season lead to crop failure. We obtain good model performance in central Europe and the eastern half of the United States, while crop failure years in regions in Asia and the western half of the United States are less accurately predicted. Model performance correlates strongly with annual mean and variability of crop yields; that is, model performance is highest in regions with relatively large annual crop yield mean and variability. Overall, for nearly all grid points, the inclusion of temperature, precipitation and vapour pressure deficit is key to predict crop failure. In addition, meteorological predictors during all seasons are required for a good prediction. These results illustrate the omnipresence of compounding effects of both meteorological drivers and different periods of the growing season for creating crop failure events. Especially vapour pressure deficit and climate extreme indicators such as diurnal temperature range and the number of frost days are selected by the statistical model as relevant predictors for crop failure at most grid points, underlining their overarching relevance. We conclude that the LASSO regression model is a useful tool to automatically detect compound drivers of extreme impacts and could be applied to other weather impacts such as wildfires or floods. As the detected relationships are of purely correlative nature, more detailed analyses are required to establish the causal structure between drivers and impacts.
Future Outlook and Scenarios
(2021)
Where is local self-government heading in the future? Among trends identified is firstly an intensification of multilevel, intermunicipal, and cross-border governance. In the future even more of cooperation and coordination among different political and administrative levels will be required. Territorial boundaries have become increasingly incongruent with functional public activities. Secondly, the innovative potential of introducing markets as templates for organisational reform has reached its end. Future reforms will most likely try to adapt market reforms to local public contexts, or even reverse the development. Finally, a tightening of state steering and an increased dependence on state funding to uphold local services is expected. Waves of amalgamations might slow down this process but they will not make financial problems disappear completely.
The digital transformation of the local public sector is an important step towards making local service delivery more citizen-centred and user-oriented. The state of digitalisation in public administration in Germany is, however, well behind the far-reaching hopes associated with this modernisation theme. This chapter will explore the question as to what extent digital tools have been introduced in German local governments, more specifically in local one-stop shops (Bürgerämter), which hurdles local actors face when coping with the digital transformation, and which tools impact on citizens and local employees as well as have unintended effects and dysfunctionalities so far. A comprehensive and standardised survey amongst mayors and heads of staff councils in German municipalities as well as citizens and employees’ surveys and case studies will form the empirical basis of this chapter.
Beyond Charter and Index
(2021)
The Chapter examines the concept of local autonomy in modern European states by analysing theoretical approaches. The classical, deductive approach defines local autonomy mostly through legal, economic and financial conditions, especially by formal structures. This proves to be too weak to define the internal strength of local authorities and their real political-administrative power. A more multidimensional definition of autonomy, including indicators as importance, capacity, as well as discretion and democracy at local level is needed. The authors utilise the indicators, used by the Local Autonomy Index (LAI) developed by Ladner et al. and the European Charter of Local Self-Government to find out what is still missing. The contribution redounds to stimulate the scientific debate on local autonomy in Europe. Until the concept of local autonomy will fit for all European states with extremely differentiated local authorities, the research in this field remains a conceptual and heuristic endeavour. Especially, because local government and democracy are until now territory-based, whereas the reality is one of multilevel and cross-border governance.
All over Europe, cities and municipalities face new and numerous challenges to uphold their unique self-governing role in society. This intriguing reality underscores this volume’s ambition of brightening the future of local self-government. After further elaborating on this relevant background and the approach taken, the first chapter introduces three main dimensions of analysis. They are key to the volume’s subsequent parts on the essence of local government’s autonomy, its transformations in the light of digitalisation, marketisation and amalgamation and, finally, its changing intergovernmental relations concerning supervision and subnational policy-making. This volume covers eight countries, spread over Europe. And so, this introductory chapter ends with highlighting main features of the different local government systems involved.
This book presents new research results on the challenges of local politics in different European countries, including Germany, the Netherlands, the Nordic countries and Switzerland, together with theoretical considerations on the further development and strengthening of local self-government. It focuses on analyses of the most recent developments in local democracy and administration. “Most ‘local government’ books are written by believers. This book is different for its realistic visions of futures of local government. It shows how autonomy, digitalization, marketization, and amalgamation could be functional or dysfunctional, and also how this is affected by links to politics, and impacted by intergovernmental relations. This is a must read for all believers in local government.” —Geert Bouckaert, KU Leuven Public Governance Institute, Belguim “The twenty chapters of this book provide a timely and thought-provoking addition to our understanding of local self-governance in eight countries in Northern and Central Europe. This book was completed shortly before the Corona-crisis crashed in. But the lessons to be learned from this volume will doubtlessly prove important in fully exploiting local government’s potential in facing the challenges of the difficult times ahead.” —Bas Denters, Professor of Public Administration, University of Twente, Netherlands “Very inspiring book that covers the most important aspects of local self-government within a comparative framework. As we might have expected, there is no general trend, no single best model but a variety of functionally equivalent settings and patterns. The book gives insight into the diversity and richness of local government, its very essence, actual challenges and transformations, and puts subnational policy making in a multi-level perspective of governance.” —Andreas Ladner, Professor for Political Institutions and Public Administration at the IDHEAP, University of Lausanne, Switzerland “Covering eight countries, this ambitious volume compares developments in local governments across Europe. Local governments are on the front-line when it comes to responding to wicked issues like climate change and migration, yet face major challenges in terms of financial and human resources. Using rich empirical evidence, the volume presents a nuanced analysis of trends. No one direction emerges for Europe’s local governments, but a rich seam of innovation is revealed covering political participation and public administration alike. Local governments have the potential to engage citizens in meaningful ways and deliver effective and responsive services, but this requires clear local leadership and support rather direction from the centre.”
Grenzland und Sarmatien
(2021)
Leveraging large-deviation statistics to decipher the stochastic properties of measured trajectories
(2021)
Extensive time-series encoding the position of particles such as viruses, vesicles, or individualproteins are routinely garnered insingle-particle tracking experiments or supercomputing studies.They contain vital clues on how viruses spread or drugs may be delivered in biological cells.Similar time-series are being recorded of stock values in financial markets and of climate data.Such time-series are most typically evaluated in terms of time-averaged mean-squareddisplacements (TAMSDs), which remain random variables for finite measurement times. Theirstatistical properties are different for differentphysical stochastic processes, thus allowing us toextract valuable information on the stochastic process itself. To exploit the full potential of thestatistical information encoded in measured time-series we here propose an easy-to-implementand computationally inexpensive new methodology, based on deviations of the TAMSD from itsensemble average counterpart. Specifically, we use the upper bound of these deviations forBrownian motion (BM) to check the applicability of this approach to simulated and real data sets.By comparing the probability of deviations fordifferent data sets, we demonstrate how thetheoretical bound for BM reveals additional information about observed stochastic processes. Weapply the large-deviation method to data sets of tracer beads tracked in aqueous solution, tracerbeads measured in mucin hydrogels, and of geographic surface temperature anomalies. Ouranalysis shows how the large-deviation properties can be efficiently used as a simple yet effectiveroutine test to reject the BM hypothesis and unveil relevant information on statistical propertiessuch as ergodicity breaking and short-time correlations.
Stereoselective [4+2] Cycloaddition of Singlet Oxygen to Naphthalenes Controlled by Carbohydrates
(2021)
Stereoselective reactions of singlet oxygen are of current interest. Since enantioselective photooxygenations have not been realized efficiently, auxiliary control is an attractive alternative. However, the obtained peroxides are often too labile for isolation or further transformations into enantiomerically pure products. Herein, we describe the oxidation of naphthalenes by singlet oxygen, where the face selectivity is controlled by carbohydrates for the first time. The synthesis of the precursors is easily achieved starting from naphthoquinone and a protected glucose derivative in only two steps. Photooxygenations proceed smoothly at low temperature, and we detected the corresponding endoperoxides as sole products by NMR. They are labile and can thermally react back to the parent naphthalenes and singlet oxygen. However, we could isolate and characterize two enantiomerically pure peroxides, which are sufficiently stable at room temperature. An interesting influence of substituents on the stereoselectivities of the photooxygenations has been found, ranging from 51:49 to up to 91:9 dr (diastereomeric ratio). We explain this by a hindered rotation of the carbohydrate substituents, substantiated by a combination of NOESY measurements and theoretical calculations. Finally, we could transfer the chiral information from a pure endoperoxide to an epoxide, which was isolated after cleavage of the sugar chiral auxiliary in enantiomerically pure form.
Nicht im Trüben fischen
(2021)
The present study aims to identify the optimal body-size/shape and maturity characteristics associated with superior fitness test performances having controlled for body-size, sex, and chronological-age differences. The sample consisted of 597 Tunisian children (396 boys and 201 girls) aged 8 to 15 years. Three sprint speeds recorded at 10, 20 and 30 m; two vertical and two horizontal jump tests; a change-of-direction and a handgrip-strength tests, were assessed during physical-education classes. Allometric modelling was used to identify the benefit of being an early or late maturer. Findings showed that being tall and light is the ideal shape to be successful at most physical fitness tests, but the height-to-weight “shape” ratio seems to be test-dependent. Having controlled for body-size/shape, sex, and chronological age, the model identified maturity-offset as an additional predictor. Boys who go earlier/younger through peak-height-velocity (PHV) outperform those who go at a later/older age. However, most of the girls’ physical-fitness tests peaked at the age at PHV and decline thereafter. Girls whose age at PHV was near the middle of the age range would appear to have an advantage compared to early or late maturers. These findings have important implications for talent scouts and coaches wishing to recruit children into their sports/athletic clubs.
This study aimed to compare the training load of a professional under-19 soccer team (U-19) to that of an elite adult team (EAT), from the same club, during the in-season period. Thirty-nine healthy soccer players were involved (EAT [n = 20]; U-19 [n = 19]) in the study which spanned four weeks. Training load (TL) was monitored as external TL, using a global positioning system (GPS), and internal TL, using a rating of perceived exertion (RPE). TL data were recorded after each training session. During soccer matches, players’ RPEs were recorded. The internal TL was quantified daily by means of the session rating of perceived exertion (session-RPE) using Borg’s 0–10 scale. For GPS data, the selected running speed intensities (over 0.5 s time intervals) were 12–15.9 km/h; 16–19.9 km/h; 20–24.9 km/h; >25 km/h (sprint). Distances covered between 16 and 19.9 km/h, > 20 km/h and >25 km/h were significantly higher in U-19 compared to EAT over the course of the study (p = 0.023, d = 0.243, small; p = 0.016, d = 0.298, small; and p = 0.001, d = 0.564, small, respectively). EAT players performed significantly fewer sprints per week compared to U-19 players (p = 0.002, d = 0.526, small). RPE was significantly higher in U-19 compared to EAT (p = 0.001, d = 0.188, trivial). The external and internal measures of TL were significantly higher in the U-19 group compared to the EAT soccer players. In conclusion, the results obtained show that the training load is greater in U19 compared to EAT.
New cryogels for selective dye removal from aqueous solution were prepared by free radical polymerization from the highly water-soluble crosslinker N,N,N’,N’-tetramethyl-N,N’-bis(2-ethylmethacrylate)-propyl-1,3-diammonium dibromide and the sulfobetaine monomer 2-(N-3-sulfopropyl-N,N-dimethyl ammonium)ethyl methacrylate. The resulting white and opaque cryogels have micrometer sized pores with a smaller substructure. They adsorb methyl orange (MO) but not methylene blue (MB) from aqueous solution. Mixtures of MO and MB can be separated through selective adsorption of the MO to the cryogels while the MB remains in solution. The resulting cryogels are thus candidates for the removal of hazardous organic substances, as exemplified by MO and MB, from water. Clearly, it is possible that the cryogels are also potentially interesting for removal of other compounds such as pharmaceuticals or pesticides, but this must be investigated further.
The objective of this book is to provide ICAO, States, competent authorities and aerodrome operators with a comprehensive overview of legal challenges related to international aerodrome planning. Answers to derived legal questions as well as recommendations thereafter shall help to enhance regulatory systems and to establish a safer aerodrome environment worldwide. Compliant aerodrome planning has an immense impact on the safety of passengers, personnel, aircraft – and of course the airport. Achieving a high safety standard is crucial, as many incidents and accidents in aviation happen at or in the vicinity of airports. Currently, more than 40% of the ICAO Member States do not fully comply with international legal requirements for aerodrome planning. Representatives of ICAO and States, as well as aerodrome and authority personnel, will understand why compliance with the different legal facets of aerodrome planning is challenging and learn how shortcomings can be solved.
Breslau has been almost entirely forgotten in the Anglophone sphere as a place of Enlightenment. Moreover, in the context of the Jewish Enlightenment, Breslau has never been discussed as a place of intercultural exchange between German-speaking Jewish, Protestant and Catholic intellectuals. The story of Moses Hirschel offers us an excellent case-study to investigate the complex reciprocal relationship between Jewish and non-Jewish enlighteners in a prosperous and influential Central European city on the cusp of the 18th century.
Lauterkeitsrecht
(2021)
Das Wettbewerbsrecht ist vor allem im Gesetz gegen den unlauteren Wettbewerb (UWG) geregelt, das den Begriff der "Lauterkeit" zur Feststellung der Zulässigkeit eines Geschäftsgebahrens verwendet. Das Rechtsgebiet wird daher in Abgrenzung zum europäischen Wettbewerbsrecht, das kartellrechtliche Fragen betrifft, auch als Lauterkeitsrecht bezeichnet.
Von besonderer Bedeutung sind die Vorgaben der europäischen Richtlinie über unlautere Geschäftspraktiken (2005/29/EG), die es bei der Auslegung des UWG stets zu beachten gilt. Die Neuauflage bringt das Werk auf den aktuellen Stand von Gesetz, Rechtsprechung und Schrifttum. Dies betrifft insbesondere das Gesetz zur Stärkung des fairen Wettbewerbs sowie einige Grundsatzentscheidungen des EuGH (zB WRP 2018, 1304 - Autorita Garante della Concorrenza del Mercato/Tre Wind u.a. und WRP 2018, 1311 - Komisia za zashtita na potrebitelite/Evelina Kamenova) und des BGH zu § 3a UWG in Verbindung mit Art. 5 Abs. 1 S. 2 GG (BGH WRP 2019, 317 - Crailsheimer Stadtblatt II), § 5 Abs. 1 UWG (BGH WRP 2019, 883 - Prämiensparverträge), § 5a UWG (zB BGH WRP 2018, 65 - MeinPaket.de II und WRP 2018, 1335 - Werbeblocker II) und § 823 Abs. 1 BGB im Hinblick auf den Eingriff in das Recht am Unternehmen durch Zusenden von Werbe-E-Mails ohne Einwilligung des Empfängers (BGH WRP 2017, 700 - Einwilligung in E-Mail-Werbung).
Das Wettbewerbsrecht ist Gegenstand des Schwerpunktbereichsstudiums. Da sich die Materie vor allem aufgrund europäischer Einflüsse im ständigen Wandel befindet, ist das Bedürfnis an einem aktuellen, aber zugleich konsequent auf Studienbedürfnisse zugeschnittenen Lehrbuch groß.
Der Grundriss stellt das aktuelle Wettbewerbsrecht studiengerecht mit vielen Übersichten, Schemata, Beispielen und einer Übungsklausur mit Lösung dar.
Vorteile auf einen Blick
- kompakte Darstellung des geltenden Rechts
- mit vielen Einstiegsfällen und Beispielen
- vom Autor des Parallelwerks Kartellrecht in der Grundriss-Reihe
Zur Neuauflage
- Mit der 4. Auflage wird das Werk auf den neuesten Stand von Rechtsprechung und europäischen Entwicklungen gebracht. Es berücksichtigt insbesondere die UWG-Novelle 2015, die das UWG grundlegend verändert hat.
Zielgruppe
Für Studierende und alle, die sich auf einfache Weise in das Wettbewerbsrecht einarbeiten wollen.
Background/objective
Dry land-training (e.g., plyometric jump training) can be a useful mean to improve swimming performance. This study examined the effects of an 8-week plyometric jump training (PJT) program on jump and sport-specific performances in prepubertal female swimmers.
Methods
Twenty-two girls were randomly assigned to either a plyometric jump training group (PJTG; n = 12, age: 10.01 ± 0.57 years, maturity-offset = -1.50 ± 0.50, body mass = 36.39 ± 6.32 kg, body height = 146.90 ± 7.62 cm, body mass index = 16.50 ± 1.73 kg/m2) or an active control (CG; n = 10, age: 10.50 ± 0.28 years, maturity-offset = -1.34 ± 0.51, body mass = 38.41 ± 9.42 kg, body height = 143.60 ± 5.05 cm, body mass index = 18.48 ± 3.77 kg/m2). Pre- and post-training, tests were conducted for the assessment of muscle power (e.g., countermovement-jump [CMJ], standing-long-jump [SLJ]). Sport-specific-performances were tested using the timed 25 and 50-m front crawl with a diving-start, timed 25-m front crawl without push-off from the wall (25-m WP), and a timed 25-m kick without push-off from the wall (25-m KWP).
Results
Findings showed a significant main effect of time for the CMJ (d = 0.78), the SLJ (d = 0.91), 25-m front crawl test (d = 2.5), and the 25-m-KWP (d = 1.38) test. Significant group × time interactions were found for CMJ, SLJ, 25-m front crawl, 50-m front crawl, 25-m KWP, and 25-m WP test (d = 0.29–1.63) in favor of PJTG (d = 1.34–3.50). No significant pre-post changes were found for CG (p > 0.05).
Conclusion
In sum, PJT is effective in improving muscle power and sport-specific performances in prepubertal swimmers. Therefore, PJT should be included from an early start into the regular training program of swimmers.