Refine
Has Fulltext
- no (2085) (remove)
Year of publication
- 2018 (2085) (remove)
Document Type
- Article (1584)
- Other (189)
- Doctoral Thesis (142)
- Review (90)
- Monograph/Edited Volume (38)
- Part of a Book (23)
- Conference Proceeding (6)
- Habilitation Thesis (5)
- Course Material (3)
- Journal/Publication series (3)
Language
Is part of the Bibliography
- yes (2085) (remove)
Keywords
- gamma rays: general (17)
- climate change (11)
- cosmic rays (11)
- stars: massive (11)
- ISM: supernova remnants (10)
- Germany (9)
- radiation mechanisms: non-thermal (9)
- German (8)
- X-rays: binaries (8)
- astroparticle physics (7)
Institute
- Institut für Biochemie und Biologie (281)
- Institut für Physik und Astronomie (279)
- Institut für Geowissenschaften (269)
- Institut für Chemie (166)
- Department Psychologie (117)
- Institut für Ernährungswissenschaft (76)
- Department Sport- und Gesundheitswissenschaften (73)
- Hasso-Plattner-Institut für Digital Engineering GmbH (73)
- Institut für Umweltwissenschaften und Geographie (71)
- Department Linguistik (68)
- Institut für Mathematik (55)
- Wirtschaftswissenschaften (53)
- Historisches Institut (46)
- Institut für Romanistik (44)
- Department Erziehungswissenschaft (38)
- Sozialwissenschaften (34)
- Institut für Informatik und Computational Science (30)
- Mathematisch-Naturwissenschaftliche Fakultät (28)
- Bürgerliches Recht (25)
- Strukturbereich Kognitionswissenschaften (23)
- Öffentliches Recht (23)
- Humanwissenschaftliche Fakultät (17)
- Fachgruppe Politik- & Verwaltungswissenschaft (15)
- Institut für Jüdische Studien und Religionswissenschaft (15)
- Institut für Germanistik (14)
- Institut für Künste und Medien (14)
- Fachgruppe Betriebswirtschaftslehre (13)
- Zentrum für Lehrerbildung und Bildungsforschung (ZeLB) (12)
- Hasso-Plattner-Institut für Digital Engineering gGmbH (11)
- Wirtschafts- und Sozialwissenschaftliche Fakultät (11)
- Department für Inklusionspädagogik (10)
- Fachgruppe Soziologie (10)
- Institut für Anglistik und Amerikanistik (10)
- Institut für Philosophie (10)
- Strafrecht (10)
- WeltTrends e.V. Potsdam (10)
- Fachgruppe Volkswirtschaftslehre (6)
- Philosophische Fakultät (6)
- Department Grundschulpädagogik (5)
- Extern (5)
- Fakultät für Gesundheitswissenschaften (5)
- Institut für Slavistik (5)
- Strukturbereich Bildungswissenschaften (3)
- Department Musik und Kunst (2)
- Kanonistisches Institut e.V. (2)
- Moses Mendelssohn Zentrum für europäisch-jüdische Studien e. V. (2)
- Potsdam Institute for Climate Impact Research (PIK) e. V. (2)
- Abraham Geiger Kolleg gGmbH (1)
- Forschungsbereich „Politik, Verwaltung und Management“ (1)
- Gesundheitsmanagement (1)
- Hochschulambulanz (1)
- Institut für Lebensgestaltung-Ethik-Religionskunde (1)
- Juristische Fakultät (1)
- Lehreinheit für Wirtschafts-Arbeit-Technik (1)
- Multilingualism (1)
- Potsdam Research Institute for Multilingualism (PRIM) (1)
- UP Transfer (1)
- Universitätsbibliothek (1)
Bürgerwindparks
(2018)
In Deutschland stößt der Ausbau der Windenergie mit dem zunehmenden Heranrücken an Wohnbebauungen immer häufiger auf Widerstand bei der lokalen Bevölkerung. Die Stärkung von Bürgerwindparks gegenüber dem alleinigen Betrieb durch große Energiekonzerne bildet die Chance wieder mehr Akzeptanz für die Windenergie zu schaffen. Das Werk widmet sich in diesem Zusammenhang einer Reihe von Fragestellungen, die verschiedene Rechtsgebiete berühren. Angesichts nur noch begrenzt zur Verfügung stehender Windenergieflächen wird untersucht, ob und mit welchen Mitteln, beispielsweise des Raumordnungs- und Bauplanungsrechts sowie vertraglicher Instrumente, Flächen speziell für Bürgerwindparks gesichert werden können.
Daneben erfährt der Leser in welchem Rahmen die Regelungen des Kommunalwirtschaftsrechts Gemeinden eine Beteiligung an Bürgerwindparks erlauben. Schließlich werden verschiedenste Gesellschaftsformen daraufhin analysiert, ob sie sich als Organisationsform eines Bürgerwindparks eignen.
Nuesiri assesses the UN-REDD (United Nations Collaborative Programme on Reducing Emissions from Deforestation and Forest Degradation in Developing Countries) commitment to strengthen local democracy as a safeguard protecting local interests in REDD+ (Reducing Emissions from Deforestation and Forest Degradation with the added goals of Conserving and Enhancing Forest Carbon Stocks, and Sustainably Managing Forests). The chapter examines local representation during the consultative process associated with the Nigeria-REDD proposal. Local representation was through selected individuals (descriptive representatives), customary authority, and NGOs (symbolic representatives). Elected local government authorities (substantive representatives) were excluded from the consultative process. Exclusion of elected local governments is linked to godfather politics in Nigeria, which enables state governors to subordinate local government authority and constrain their responsiveness to local needs. In approving the Nigeria-REDD proposal, the UN-REDD reinforced the subversion of local democracy in Nigeria. The UN-REDD would be fulfilling its democracy objectives in Nigeria by engaging substantively all local governance actors, including elected local government authorities.
This edited collection assesses governance in forestry programmes and projects, including REDD+ governance. It examines political representation, participation and decentralisation in forest governance, providing insight as to how forest governance arrangements can be responsive to the socio-economic interests of local people and communities who live adjacent to and depend on forests.
Global Forest Governance and Climate Change argues that inclusive complementary representation of local communities is required for strong participatory processes and democratic decentralisation of forest governance. Responsiveness to local people's socio-economic interests in forestry initiatives require paying attention to not just the hosting of participatory meetings and activities, but also to the full cast of appointed, self-authorized, and elected representative agents that stand, speak, and act for local people.
This book will be of interest to students and academics across the fields of climate change governance, forestry, development studies, and political economy. It will also be a useful resource for policy makers and practitioners responsible for forestry and climate change initiatives.
Welle der Konsumgesellschaft
(2018)
Wie beeinflussten sich Massenmedien und Massenkonsum im Frankreich der Nachkriegszeit gegenseitig?
Radio Luxembourg war in der europäischen Rundfunklandschaft der Nachkriegszeit eine Ausnahme: Die privatkommerzielle Radiostation sendete werbefinanzierte Unterhaltungsprogramme in die benachbarten Staaten und erreichte damit ein Millionenpublikum. Die Autorin Anna Jehle zeigt anhand verschiedener Untersuchungsfelder - der Unternehmens- und Programmgeschichte, der Zielgruppen, der Marketingaktivitäten und des Werbezeitenverkaufs -, wie eng die Entwicklung der Konsumgesellschaft im Frankreich der sogenannten trente glorieuses mit der Verbreitung und Nutzung des Radios verbunden war. Mit seinem ganz auf Massenkonsum ausgerichteten Rundfunkkonzept war Radio Luxembourg nicht nur integraler Bestandteil, sondern auch Katalysator und Agent der Konsummoderne. Dies hatte weitreichende Auswirkungen für das französische Rundfunksystem, das sich unter dem Einfluss Radio Luxembourgs kommerzialisierte, und zwar bereits lange vor der Deregulierung des Rundfunks in den 1980er Jahren.
A considerable number of systems have recently been reported in which
Brownian yet non-Gaussian dynamics was observed. These are processes characterised by a linear growth in time of the mean squared displacement, yet the probability density function of the particle displacement is distinctly non-Gaussian, and often of exponential(Laplace) shape. This apparently ubiquitous behaviour observed in very different physical systems has been interpreted as resulting from diffusion in inhomogeneous environments and mathematically represented through a variable, stochastic diffusion coefficient. Indeed different models describing a fluctuating diffusivity have been studied. Here we present a new view of the stochastic basis describing time dependent random diffusivities within a broad spectrum of distributions. Concretely, our study is based on the very generic class of the generalised Gamma distribution. Two models for the particle spreading in such random diffusivity settings are studied. The first belongs to the class of generalised grey Brownian motion while the second follows from the idea of diffusing diffusivities. The two processes exhibit significant characteristics which reproduce experimental results from different biological and physical systems. We promote these two physical models for the description of stochastic particle motion in complex environments.
High-throughput sequence data retrieved from ancient or other degraded samples has led to unprecedented insights into the evolutionary history of many species, but the analysis of such sequences also poses specific computational challenges. The most commonly used approach involves mapping sequence reads to a reference genome. However, this process becomes increasingly challenging with an elevated genetic distance between target and reference or with the presence of contaminant sequences with high sequence similarity to the target species. The evaluation and testing of mapping efficiency and stringency are thus paramount for the reliable identification and analysis of ancient sequences. In this paper, we present ‘TAPAS’, (Testing of Alignment Parameters for Ancient Samples), a computational tool that enables the systematic testing of mapping tools for ancient data by simulating sequence data reflecting the properties of an ancient dataset and performing test runs using the mapping software and parameter settings of interest. We showcase TAPAS by using it to assess and improve mapping strategy for a degraded sample from a banded linsang (Prionodon linsang), for which no closely related reference is currently available. This enables a 1.8-fold increase of the number of mapped reads without sacrificing mapping specificity. The increase of mapped reads effectively reduces the need for additional sequencing, thus making more economical use of time, resources, and sample material.
Power training programs have proved to be effective in improving components of physical fitness such as speed. According to the concept of training specificity, it was postulated that exercises must attempt to closely mimic the demands of the respective activity. When transferring this idea to speed development, the purpose of the present study was to examine the effects of resisted sprint (RST) vs. traditional power training (TPT) on physical fitness in healthy young adults. Thirty-five healthy, physically active adults were randomly assigned to a RST (n = 10, 23 ± 3 years), a TPT (n = 9, 23 ± 3 years), or a passive control group (n = 16, 23 ± 2 years). RST and TPT exercised for 6 weeks with three training sessions/week each lasting 45–60 min. RST comprised frontal and lateral sprint exercises using an expander system with increasing levels of resistance that was attached to a treadmill (h/p/cosmos). TPT included ballistic strength training at 40% of the one-repetition-maximum for the lower limbs (e.g., leg press, knee extensions). Before and after training, sprint (20-m sprint), change-of-direction speed (T-agility test), jump (drop, countermovement jump), and balance performances (Y balance test) were assessed. ANCOVA statistics revealed large main effects of group for 20-m sprint velocity and ground contact time (0.81 ≤ d ≤ 1.00). Post-hoc tests showed higher sprint velocity following RST and TPT (0.69 ≤ d ≤ 0.82) when compared to the control group, but no difference between RST and TPT. Pre-to-post changes amounted to 4.5% for RST [90%CI: (−1.1%;10.1%), d = 1.23] and 2.6% for TPT [90%CI: (0.4%;4.8%), d = 1.59]. Additionally, ground contact times during sprinting were shorter following RST and TPT (0.68 ≤ d ≤ 1.09) compared to the control group, but no difference between RST and TPT. Pre-to-post changes amounted to −6.3% for RST [90%CI: (−11.4%;−1.1%), d = 1.45) and −2.7% for TPT [90%CI: (−4.2%;−1.2%), d = 2.36]. Finally, effects for change-of-direction speed, jump, and balance performance varied from small-to-large. The present findings indicate that 6 weeks of RST and TPT produced similar effects on 20-m sprint performance compared with a passive control in healthy and physically active, young adults. However, no training-related effects were found for change-of-direction speed, jump and balance performance. We conclude that both training regimes can be applied for speed development.
Abstract. The aim of this study is to investigate the shallow thermal field differences for two differently aged passive continental margins by analyzing regional variations in geothermal gradient and exploring the controlling factors for these variations. Hence, we analyzed two previously published 3-D conductive and lithospheric-scale thermal models of the Southwest African and the Norwegian passive margins. These 3-D models differentiate various sedimentary, crustal, and mantle units and integrate different geophysical data such as seismic observations and the gravity field. We extracted the temperature–depth distributions in 1 km intervals down to 6 km below the upper thermal boundary condition. The geothermal gradient was then calculated for these intervals between the upper thermal boundary condition and the respective depth levels (1, 2, 3, 4, 5, and 6 km below the upper thermal boundary condition). According to our results, the geothermal gradient decreases with increasing depth and shows varying lateral trends and values for these two different margins. We compare the 3-D geological structural models and the geothermal gradient variations for both thermal models and show how radiogenic heat production, sediment insulating effect, and thermal lithosphere–asthenosphere boundary (LAB) depth influence the shallow thermal field pattern. The results indicate an ongoing process of oceanic mantle cooling at the young Norwegian margin compared with the old SW African passive margin that seems to be thermally equilibrated in the present day.
Previous research has indicated that executive function (EF) is negatively associated with aggressive behavior in childhood. However, there is a lack of longitudinal studies that have examined the effect of deficits in EF on aggression over time and taken into account different forms and functions of aggression at the same time. Furthermore, only few studies have analyzed the role of underlying variables that may explain the association between EF and aggression. The present study examined the prospective paths between EF and different forms (physical and relational) and functions (reactive and proactive) of aggression. The habitual experience of anger was examined as a potential underlying mechanism of the link between EF and aggression, because the tendency to get angry easily has been found to be both a consequence of deficits in EF and a predictor of aggression. The study included 1,652 children (between 6 and 11 years old at the first time point), who were followed over three time points (T1, T2, and T3) covering 3 years. At T1, a latent factor of EF comprised measures of planning, rated via teacher reports, as well as inhibition, set shifting, and working-memory updating, assessed experimentally. Habitual anger experience was assessed via parent reports at T1 and T2. The forms and functions of aggression were measured via teacher reports at all three time points. Structural equation modeling revealed that EF at T1 predicted physical, relational, and reactive aggression at T3, but was unrelated to proactive aggression at T3. Furthermore, EF at T1 was indirectly linked to physical aggression at T3, mediated through habitual anger experience at T2. The results indicate that deficits in EF influence the later occurrence of aggression in middle childhood, and the tendency to get angry easily mediates this relation.
Recent advances in single particle tracking and supercomputing techniques demonstrate the emergence of normal or anomalous, viscoelastic diffusion in conjunction with non-Gaussian distributions in soft, biological, and active matter systems. We here formulate a stochastic model based on a generalised Langevin equation in which non-Gaussian shapes of the probability density function and normal or anomalous diffusion have a common origin, namely a random parametrisation of the stochastic force. We perform a detailed analysis demonstrating how various types of parameter distributions for the memory kernel result in exponential, power law, or power-log law tails of the memory functions. The studied system is also shown to exhibit a further unusual property: the velocity has a Gaussian one point probability density but non-Gaussian joint distributions. This behaviour is reflected in the relaxation from a Gaussian to a non-Gaussian distribution observed for the position variable. We show that our theoretical results are in excellent agreement with stochastic simulations.
Background
The unisexual Amazon molly (Poecilia formosa) originated from a hybridization between two sexual species, the sailfin molly (Poecilia latipinna) and the Atlantic molly (Poecilia mexicana). The Amazon molly reproduces clonally via sperm-dependent parthenogenesis (gynogenesis), in which the sperm of closely related species triggers embryogenesis of the apomictic oocytes, but typically does not contribute genetic material to the next generation. We compare for the first time the gonadal transcriptome of the Amazon molly to those of both ancestral species, P. mexicana and P. latipinna.
Results
We sequenced the gonadal transcriptomes of the P. formosa and its parental species P. mexicana and P. latipinna using Illumina RNA-sequencing techniques (paired-end, 100 bp). De novo assembly of about 50 million raw read pairs for each species was performed using Trinity, yielding 106,922 transcripts for P. formosa, 115,175 for P. latipinna, and 133,025 for P. mexicana after eliminating contaminations. On the basis of sequence similarity comparisons to other teleost species and the UniProt databases, functional annotation, and differential expression analysis, we demonstrate the similarity of the transcriptomes among the three species. More than 40% of the transcripts for each species were functionally annotated and about 70% were assigned to orthologous genes of a closely related species. Differential expression analysis between the sexual and unisexual species uncovered 2035 up-regulated and 564 down-regulated genes in P. formosa. This was exemplary validated for six genes by qRT-PCR.
Conclusions
We identified more than 130 genes related to meiosis and reproduction within the apomictically reproducing P. formosa. Overall expression of these genes seems to be down-regulated in the P. formosa transcriptome compared to both ancestral species (i.e., 106 genes down-regulated, 29 up-regulated). A further 35 meiosis and reproduction related genes were not found in the P. formosa transcriptome, but were only expressed in the sexual species. Our data support the hypothesis of general down-regulation of meiosis-related genes in the apomictic Amazon molly. Furthermore, the obtained dataset and identified gene catalog will serve as a resource for future research on the molecular mechanisms behind the reproductive mode of this unisexual species.
Ostdeutsche Ehen vor Gericht
(2018)
Die DDR hatte eine der weltweit höchsten Scheidungsraten. Die Ehescheidung war mit nur wenigen Hürden verbunden und wurde weitgehend als Privatsache betrachtet. Doch ab 1990 trafen ost- und westdeutsche Bürger und Juristen
mit unterschiedlichen Erfahrungen aufeinander. Anja Schröter betrachtet die Scheidungspraxis in Ostdeutschland vom letzten Jahrzehnt der DDR über die Epochenzäsur 1989/90 hinweg bis zur Jahrtausendwende. Sie hat Juristen und ostdeutsche Bürger nach ihren Erfahrungen gefragt. Eine faszinierende Studie zum ostdeutschen Alltag im Umbruch.
The ongoing trend of miniaturizing multifunctional devices, especially for minimally-invasive medical or sensor applications demands new strategies for designing the required functional polymeric micro-components or micro-devices. Here, polymers, which are capable of active movement, when an external stimulus is applied (e.g. shape-memory polymers), are intensively discussed as promising material candidates for realization of multifunctional micro-components. In this context further research activities are needed to gain a better knowledge about the underlying working principles for functionalization of polymeric micro-scale objects with a shape-memory effect. First reports about electrospun solid microfiber scaffolds, demonstrated a much more pronounced shape-memory effect than their bulk counterparts, indicating the high potential of electrospun micro-objects.
Based on these initial findings this thesis was aimed at exploring whether the alteration of the geometry of micro-scale electrospun polymeric objects can serve as suitable parameter to tailor their shape-memory properties. The central hypothesis was that different geometries should result in different degrees of macromolecular chain orientation in the polymeric micro-scale objects, which will influence their mechanical properties as well as thermally-induced shape-memory function. As electrospun micro-scale objects, microfiber scaffolds composed of hollow microfibers with different wall thickness and electrosprayed microparticles as well as their magneto-sensitive nanocomposites all prepared from the same polymer exhibiting pronounced bulk shape-memory properties were investigated. For this work a thermoplastic multiblock copolymer, named PDC, with excellent bulk shape-memory properties, associated with crystallizable oligo(ε-caprolactone) (OCL) switching domains, was chosen for the preparation of electrospun micro-scale objects, while crystallizable oligo(p-dioxanone) (OPDO) segments serve as hard domains in PDC.
In the first part of the thesis microfiber scaffolds with different microfiber geometries (solid or hollow with different wall thickness) were discussed. Hollow microfiber based PDC scaffolds were prepared by coaxial electrospinning from a 1, 1, 1, 3, 3, 3 hexafluoro-2-propanol (HFP) solution with a polymer concentration of 13% w·v-1. Here as a first step core-shell fiber scaffolds consisting of microfibers with a PDC shell and sacrificial poly(ethylene glycol) (PEG) core are generated. The hollow PDC microfibers were achieved after dissolving the PEG core with water. The utilization of a fixed electrospinning setup and the same polymer concentration of the PDC spinning solution could ensure the fabrication of microfibers with almost identical outer diameters of 1.4 ± 0.3 µm as determined by scanning electron microscopy (SEM). Different hollow microfiber wall thicknesses of 0.5 ± 0.2 and 0.3 ± 0.2 µm (analyzed by SEM) have been realized by variation of the mass flow rate, while solid microfibers were obtained by coaxial electrospinning without supplying any core solution. Differential scanning calorimetry experiments and tensile tests at ambient temperature revealed an increase in degree of OCL crystallinity form χc,OCL = 34 ± 1% to 43 ± 1% and a decrease in elongation of break from 800 ± 40% to 200 ± 50% associated with an increase in Young´s modulus and failture stress for PDC hollow microfiber scaffolds when compared with soild fibers. The observed effects were enhanced with decreasing wall thickness of the single hollow fibers. The shape-memory properties of the electrospun PDC scaffolds were quantified by cyclic, thermomechanical tensile tests. Here, scaffolds comprising hollow microfibers exhibited lower shape fixity ratios around Rf = 82 ± 1% and higher shape recovery ratios of Rr = 67 ± 1% associated to more pronounced relaxation at constant strain during the first test cycle and a lower switching temperature of Tsw = 33 ± 1 °C than the fibrous meshes consisting of solid microfibers. These findings strongly support the central hypothesis that different fiber geometries (solid or hollow with different wall thickness) in electrospun scaffolds result in different degrees of macromolecular chain orientation in the polymeric micro-scale objects, which can be applied as design parameter for tailoring their mechanical and shape-memory properties.
The second part of the thesis deals with electrosprayed particulate PDC micro-scale objects. Almost spherical PDC microparticles with diameters of 3.9 ± 0.9 μm (as determined by SEM) were achieved by electrospraying of HFP solution with a polymer concentration of 2% w·v-1. In contrast, smaller particles with sizes of 400 ± 100 nm or 1.2 ± 0.3 μm were obtained for the magneto-sensitive composite PDC microparticles containing 23 ± 0.5 wt% superparamagnetic magnetite nanoparticles (mNPs). All prepared PDC microparticles exhibited a similar overall crystallinity like the PDC bulk material as analyzed by DSC. AFM nanoindentation results revealed no influence of the nanofiller incorporation on the local mechanical properties represented by the reduced modulus determined for pure PDC microparticles and magneto-sensitive composite PDC microparticles with similar diameters around 1.3 µm. It was found that the reduced modulus of the nanocomposite microparticles increased substantially with decreasing particles size from 2.4 ± 0.9 GPa (1.2 µm) to 11.9 ± 3.1 GPa (0.4 µm), which can be related to a higher orientation of the macromolecules at the surface of smaller sized microparticles. The magneto-sensitivity of such nanocomposite microparticles could be demonstrated in two aspects. One was by attracting/collecting the composite micro-objects with an external permanent magnet. The other one was by a inductive heating to 44 ± 1 °C, which is well above the melting transition of the OCL switching domains, when compacted to a 10 x 10 mm2 film with a thickness of 10 µm and exposed to an alternating magnet field with an magnetic field strength of 30 kA·m-1. Both functions are of great relevance for designing next generation drug delivery systems combining targeting and on demand release.
By a compression approach shape-memory functionalization of individual microparticles could be realized. Here different programming pressures and compression temperatures were applied. The shape-recovery capability of the programmed PDC microparticles was quantified by online and off-line heating experiments analyzed via microscopy measurement. The obtained shape-memory properties were found to be strongly depending on the applied programming pressure and temperature. The best shape-memory performance with a high shape recovery rate of about Rr = 80±1% was obtained when a low pressure of 0.2 MPa was applied at 55 °C. Finally, it was demonstrated that PDC microparticles can be utilized as micro building parts for preparation of a macroscopic film with temporary stability by compression of a densely packed array of PDC microparticles at 60 °C followed by subsequent cooling to ambient temperature. This film disintegrates into individual microparticles upon heating to 60 °C. Based on this technology the design of stable macroscopic release systems can be envisioned, which can be easily fixed at the site of treatment (i.e. by suturing) and disintegrate on demand to microparticles facilitating the drug release.
In summary, the results of this thesis could confirm the central hypothesis that the variation of the geometry of polymeric micro-objects is a suitable parameter to adjust their shape-memory performance by changing the degree of macromolecular chain orientation in the specimens or by enabling new functions like on demand disintegration. These fundamental findings might be relevant for designing novel miniaturized multifunctional polymer-based devices.
Polymeric materials, which can perform reversible shape changes after programming, in response to a thermal or electrical stimulation, can serve as (soft) actuating components in devices like artificial muscles, photonics, robotics or sensors. Such polymeric actuators can be realized with hydrogels, liquid crystalline elastomers, electro-active polymers or shape-memory polymers by controlling with stumuli such as heat, light, electrostatic or magnetic field. If the application conditions do not allow the direct heating or electric stimulation of these smart devices, noncontact triggering will be required. Remotely controlled actuation have been reported for liquid crystalline elastomer composites or shape-memory polymer network composites, when a persistent external stress is applied during inductive heating in an alternating magnetic field. However such composites cannot meet the demands of applications requiring remotely controlled free-standing motions of the actuating components.
The current thesis investigates, whether a reprogrammable remotely controlled soft actuator can be realized by magneto-sensitive multiphase shape-memory copolymer network composites containing magnetite nanoparticles as magneto-sensitive multivalent netpoints. A central hypothesis was that a magnetically controlled two-way (reversible bidirectional) shape-memory effect in such nanocomposites can be achieved without application of external stress (freestanding), when the required orientation of the crystallizable actuation domains (ADs) can be ensured by an internal skeleton like structure formed by a second crystallizable phase determing the samples´s geometry, while magneto-sensitive iron oxide nanoparticles covalently integrated in the ADs allow remote temperature control. The polymer matrix of these composites should exhibit a phase-segregated morphology mainly composed of cyrstallizable ADs, whereby a second set of higher melting crystallites can take a skeleton like, geometry determining function (geometry determining domains, GDs) after programming of the composite and in this way the orientation of the ADs is established and maintained during actuation. The working principle for the reversible bidirectional movements in the multiphase shape-memory polymer network composite is related to a melting-induced contraction (MIC) during inductive heating and the crystallization induced elongation (CIE) of the oriented ADs during cooling. Finally, the amount of multivalent magnetosensitive netpoints in such a material should be as low as possible to ensure an adequate overall elasticity of the nanocomposite and at the same time a complete melting of both ADs and GDs via inductive heating, which is mandatory for enabling reprogrammability.
At first, surface decorated iron oxide nanoparticles were synthesized and investigated. The coprecipitation method was applied to synthesize magnetic nanoparticles (mNPs) based on magnetite with size of 12±3 nm and in a next step a ring-opening polymerization (ROP) was utilized for covalent surface modification of such mNPs with oligo(ϵ-caprolactone) (OCL) or oligo(ω-pentadecalactone) (OPDL) via the “grafting from” approach. A successful coating of mNPs with OCL and OPDL was confirmed by differential scanning calorimetry (DSC) experiments showing melting peaks at 52±1 °C for mNP-OCL and 89±1 °C for mNP-OPDL. It was further explored whether two-layered surface decorated mNPs, can be prepared via a second surface-initiated ROP of mNP-OCL or mNP-OPDL with ω-pentadecalactone or ϵ-caprolactone. The observation of two distinct melting transitions in DSC experiments as well as the increase in molecular weight of the detached coatings determined by GPC and 1H-NMR indicated a successful synthesis of the twolayered nanoparticles mNP-OCL-OPDL and mNP-OPDL-OCL. In contrast TEM micrographs revealed a reduction of the thickness of the polymeric coating on the nanoparticles after the second ROP, indicating that the applied synthesis and purification required further optimization.
For evaluating the impact of the dispersion of mNPs within a polymer matrix on the resulting inductive heating capability of composites, plain mNPs as well as OCL coated magnetite nanoparticles (mNP-OCLs) were physically incorporated into crosslinked poly(ε-caprolactone) (PCL) networks. Inductive heating experiments were performed with both networks cPCL/mNP and cPCL/mNP-OCL in an alternating magnetic field (AMF) with a magnetic field strength of H = 30 kA·m-1. Here a bulk temperature of Tbulk = 74±2 °C was achieved for cPCL/mNP-OCL, which was almost 20 °C higher than the melting transition of the PCL-based polymer matrix. In contrast, the composite with plain mNPs could only reach a Tbulk of 48±2 °C, which is not sufficient for a complete melting of all PCL crystallites as required for actuation.
The inductive heating capability of a multiphase copolymer nanocomposite network (designed as soft actuators) containing surface decorated mNPs as covalent netpoints was investigated. Such composite was synthesized from star-shaped OCL and OPDL precursors, as well as mNP-OCLs via reaction with HDI. The weight ratio of OPDL and OCL in the starting reaction mixture was 15/85 (wt%/wt%) and the amount of iron oxide in the nanocomposite was 4 wt%. DSC experiments revealed two well separated melting and crystallization peaks confirming the required phase-segregated morphology in the nanocomposite NC-mNP-OCL. TEM images could illustrate a phase-segregated morphology of the polymer matrix on the microlevel with droplet shaped regions attributed to the OPDL domains dispersed in an OCL matrix. The TEM images could further demonstrate that the nanoparticulate netpoints in NC-mNP-OCL were almost homogeneously dispersed within the OCL domains. The tests of the inductive heating capability of the nanocomposites at a magnetic field strength of Hhigh = 11.2 kA·m-1 revealed a achievable plateau surface temperature of Tsurf = 57±1 °C for NC-mNP-OCL recorded by an infrared video camera. An effective heat generation constant (̅P) can be derived from a multi-scale model for the heat generation, which is proportional to the rate of heat generation per unit volume of the sample. NC-mNP-OCL with homogeneously dispersed mNP-OCLs exhibited a ̅P value of 1.04±0.01 K·s- 1 at Hhigh, while at Hreset = 30.0 kA·m-1 a Tsurf of 88±1 °C (where all OPDL related crystallite are molten) and a ̅P value of 1.93±0.02 K·s-1 was obtained indicating a high magnetic heating capability of the composite.
The free-standing magnetically-controlled reversible shape-memory effect (mrSME) was explored with originally straight nanocomposite samples programmed by bending to an angle of 180°. By switching the magnetic field on and off the composite sample was allowed to repetitively heat to 60 °C and cool to the ambient temperature. A pronounced mrSME, characterized by changes in bending angle of Δϐrev = 20±3° could be obtained for a composite sample programmed by bending when a magnetic field strength of Hhigh = 11.2 kA·m-1 was applied in a multi-cyclic magnetic bending experiment with 600 heating-cooling cycles it could be shown that the actuation performance did not change with increasing number of test cycles, demonstrating the accuracy and reproducibility of this soft actuator. The degree of actuation as well as the kinetics of the shape changes during heating could be tuned by variation of the magnetic filed strength between Hlow and Hhigh or the magnetic field exposure time. When Hreset = 30.0 kA·m-1 was applied the programmed geometry was erased and the composite sample returned to it´s originally straight shape. The reprogrammability of the nanocomposite actuators was demonstrated by one and the same test specimen first exhibiting reversible angle changes when programmed by bending, secondly reprogrammed to a concertina, which expands upon inductive heating and contracts during cooling and finally reprogrammed to a clip like shape, which closes during cooling and opens when Hhigh was applied. In a next step the applicability of the presented remote controllable shape-memory polymer actuators was demonstrated by repetitive opening and closing of a multiring device prepared from NC-mNP-OCL, which repetitively opens and closes when a alternating magnetic field (Hhigh = 11.2 kA·m-1) was switched on and off.
For investigation of the micro- and nanostructural changes related to the actuation of the developed nanocomposite, AFM and WAXS experiments were conducted with programmed nanocomposite samples under cyclic heating and cooling between 25 °C and 60 °C. In AFM experiments the change in the distance (D) between representative droplet-like structures related to the OPDL geometry determining domains was used to calculate the reversible change in D. Here Drev = 3.5±1% was found for NC-mNP-OCL which was in good agreement with the results of the magneto-mechanical actuation experiments. Finally, the analysis of azimuthal (radial) WAXS scattering profiles could support the oriented crystallization of the OCL actuation domains at 25 °C.
In conclusion, the results of this work successfully demonstrated that shape-memory polymer nanocomposites, containing mNPs as magneto-sensitive multifunctional netpoints in a covalently crosslinked multiphase polymer matrix, exhibit magnetically (remotely) controlled actuations upon repetitive exposure to an alternating magnetic field. Furthermore, the (shape) memory of such a nanocomposite can be erased by exposing it to temperatures above the melting temperature of the geometry forming domains, which allows a reprogramming of the actuator. These findings would be relevant for designing novel reprogrammable remotely controllable soft polymeric actuators.
Handelsrecht
(2018)
Zum Werk
Dieses Lehrbuch erläutert anschaulich und didaktisch ausgefeilt das im juristischen und wirtschaftswissenschaftlichen Studium sowie in der Praxis bedeutsame Sonderprivatrecht der Kaufleute. Es behandelt die Materie umfassend und fundiert.
Ein Schwerpunkt liegt u.a. auf dem Verhältnis von BGB- und HGB-Regelungen.
Das Werk besticht durch eine klare Gliederung des Stoffes. Die einprägsame Sprache und die tiefgründige Durchdringung des Stoffes machen das Buch nicht nur für Studierende, sondern auch für Spezialisten lesenswert.
Inhalt
- Kaufleute
- Handels- und Unternehmensregister
- Übertragung und Vererbung des kaufmännischen Unternehmens
- Unternehmen und Firma
- Prokura, Handlungsvollmacht, Ladenvollmacht, Scheinvollmacht
- Handelsvertreter, Kommissionsagent, Vertragshändler etc.
- Handelsbücher
- Handelsgeschäfte, Verhältnis zum allgemeinen und besonderen Schuldrecht
- Handelsgeschäfte und Sachenrecht
- Kommission, Fracht-, Speditions- und Lagergeschäft
Vorteile auf einen Blick
- mit Merksätzen und Übersichten
- prägnante Darstellung
- optimaler Zuschnitt auf studentische Bedürfnisse
- Veranschaulichung der Inhalte durch Fallbeispiele
Zur Neuauflage
Die Neuauflage bringt das Werk auf den neusten Stand der Gesetzgebung, Rechtsprechung und Literatur. Insbesondere wurden die jüngsten Entwicklungen auf europäischer Ebene sowie im HGB und UWG berücksichtigt.
Zielgruppe
Für Studierende der Rechts- und Wirtschaftswissenschaften.
Das Werk unternimmt eine erstmalige zusammenfassende Darstellung der Umsatzbesteuerung von Energieleistungen sowie deren mehrwertsteuerrechtlichen Beurteilung unter besonderer Berücksichtigung aktueller Probleme und Zweifelsfragen. Hierfür werden Problembereiche grundlegend und rechtsdogmatisch beleuchtet. Ziel der Arbeit ist es, die wesentlichen Geschäftspraktiken im Energiesektor einer mehrwertsteuerrechtlichen Analyse zu unterwerfen, die stets das unionsrechtliche Mehrwertsteuerrecht und das nationale Umsatzsteuerrecht betrachtet. Es wird untersucht, ob und inwieweit die gegenwärtigen Vorschriften zur umsatzsteuerrechtlichen Behandlung von Energieleistungen mit dem europäischen Unionsrecht vereinbar, praxistauglich und angemessen sind. Im Lichte der unaufhaltsam voranschreitenden Energiewende will die vorliegende Untersuchung einen systemimmanenten Überblick der energierechtlichen Implikationen auf das Mehrwertsteuerrecht in einem einheitlichen mehrwertsteuerrechtlichen Gesamtkontext geben.
Direkte Arylierung
(2018)
Die Arbeit widmet sich den Haushaltssperren auf den verschiedenen Ebenen und untersucht, ob ein einheitliches Instrument der Haushaltssperre im deutschen Recht existiert, oder ob sich hinter dem Begriff der Haushaltssperre verschiedene haushaltsrechtliche Maßnahmen verbergen. Dazu werden auf verfassungsrechtlicher Ebene der Aspekt der Gewaltenteilung gemäß Art. 20 II 2 GG sowie die kommunale Selbstverwaltungsgarantie des Art. 28 II GG betrachtet. Auf Bundes-, Landes- und kommunaler Ebene werden u.a. Sperrvermerke, Globale Minderausgaben, haushaltswirtschaftliche Sperren sowie Bewirtschaftungssperren eingehend dargestellt und erörtert. Ergänzend werden Aspekte wie weitere Instrumente zur Kontrolle des Haushalts und Rechtsschutz gegen Haushaltssperren dargestellt und Regelungsvorschläge unterbreitet. Im Fazit wird festgestellt, dass »Haushaltssperren« zu komplex und unterschiedlich sind, um ein einheitliches Institut der Haushaltssperre darstellen zu können.
Ceauşescus Polizei
(2018)
Das Buch behandelt die gesellschaftliche Wirkung der sozialistischen Volkspolizei, indem es offizielle Bilder derselben in den Jahren vor dem Ceaușescu-Regime und während desselben mit Vorstellungen vergleicht, die in der Bevölkerung von der Polizei bestanden. Damit enthüllt das Buch zugleich das Verhältnis zwischen dem staatlichen Ordnungsdiskurs und einem Gegendiskurs, der ansatzweise sogar vor 1989 stattgefunden hat. Vorrangiges Ziel ist ein klareres Verständnis des (De-)Legitimierungsprozesses des Regimes. Eine Interdependenz der beiden Diskurse, so die Grundaussage des Buches, diente zunächst der Stabilitätsphase des politischen Regimes, bedingte später dann aber zum Teil den schrittweisen Kollaps seiner Herrschaft in Rumänien. In einem weiteren Sinne untermauern die Erkenntnisse über die Entzauberung des sozialistischen "Ordnungshüters" das bessere Verstehen der allgemeinen sozialpolitischen Ernüchterung in Mittelost- und Südosteuropa gegen 1989 hin. Zahlreiche Widersprüche auf der Ebene der Repräsentation untermauern die Hypothese einer De-Legitimation der Volkspolizei als Institution und nicht zuletzt deshalb im Weiteren des politischen Regimes im Allgemeinen.
Dass sich die repräsentative Demokratie in Deutschland im Wandel befindet, ist nicht neu und kaum umstritten. Herausforderungen im Kontext der Partizipation und Repräsentation rufen ihrerseits Probleme auf Seiten der Input-Legitimation hervor. Demgemäß ist das grundlegende demokratiepolitische Anliegen dieser Arbeit, am Beispiel der Bundes- und Berliner Landesebene darzustellen, wie der repräsentative Politikprozess partizipativer und dennoch effektiv gestaltet werden kann. Basierend auf der philosophischen Strömung des Pragmatismus verfolgt und diskutiert die Arbeit die Synthese aus der pragmatistischen Demokratiekonzeption von Archon Fung und dem empirischen Forschungsprogramm der kriterienbasierten Evaluation demokratischer Innovationen. Dabei wird das analytische Vorgehen Archon Fungs kritisch erweitert, um dem dieser Arbeit zugrunde liegenden Konzept einer komplexen Bürgergesellschaft – als normativer und praktischer Bezugspunkt – gerecht zu werden. Fungs Konzept wird demnach um die liberale Sphäre der Öffentlichkeit, mithin um die zivilgesellschaftlichen Handlungszusammenhänge ergänzt. Auf Grundlage der Diskussion von demokratischen Innovationen werden schließlich demokratie- und engagementpolitische Handlungsempfehlungen in der Dimension der Partizipation und in der Dimension der Repräsentation formuliert. Mithin verfolgt die Arbeit eine problem- und lösungsorientierte Ergänzung der repräsentativen Demokratie. Gleichwohl ist die Arbeit als eine pragmatistisch angeleitete Konzeptstudie für die Entwicklung einer beteiligungsorientierten Praxis in der repräsentativen Demokratie zu verstehen, die trotz ihres theoretischen Charakters ganz im Sinne des Pragmatismus die notwendige empirische Orientierung aufweist. Damit wird das zuweilen problematische Verhältnis zwischen Politischer Theorie und empirischer Demokratieforschung überwunden.
Companies have a keen interest in developing skilled negotiators in order to improve their negotiation outcome. A crucial determinant of the negotiation outcome are negotiation styles that represent the negotiator’s actual behavior during the negotiation process. In this context, the author examines the variation in negotiation styles throughout the negotiation process, points out the relevance of the negotiator’s characteristics and situational context as determinants of negotiation styles, and emphasizes the importance not only of actual but also of perceived negotiation behavior. As a result, existing negotiation research is advanced as new perspectives on negotiation styles are offered to improve a negotiator’s performance.
Bleiben in Breslau
(2018)
Der Breslauer Jude Willy Cohn musste nach der Machtübernahme der Nationalsozialisten erleben, wie die deutschen Juden in immer größerem Umfang entrechtet, ausgegrenzt und existenziell bedroht werden. Trotzdem kam eine Auswanderung aus Deutschland als seiner Heimat für ihn letztlich nicht in Betracht. Im Winter 1941 wurde Willy Cohn mit seiner Familie aus Breslau deportiert und von den Nationalsozialisten ermordet.
Ausgehend von Cohns Entscheidung, in Breslau zu bleiben, betrachtet die Untersuchung das Bleiben als Aushandlungsprozess und macht so exemplarisch das Bleiben im NS-Deutschland als Akt der Selbstbehauptung sichtbar. Hierfür wurde der rund 10.000 Seiten umfassende Tagebuchnachlass Willy Cohns aus den Jahren zwischen 1899 und 1941 erstmals in seiner Gesamtheit systematisch gesichtet und ausgewertet.
Der Autor entwickelt ein Modell des strategischen und operativen Managements in Konzernrechtsabteilungen und richtet dabei den Fokus auf praktische Erkenntnisse, die auf betriebs- und volkswirtschaftlichen Theorien sowie zahlreichen Experteninterviews aufgebaut sind. Ein besonderes Augenmerk legt er auf die Spezifika von Rechtsdienstleistungen im Vergleich zu anderen Leistungen, die in einem Konzern benötigt werden. Die Sichtweise des Leiters einer Rechtsabteilung /General Counsels steht dabei im Vordergrund. Es wird die Frage untersucht, wie dieser die Leitung und Steuerung der gesamten Abteilung am effizientesten und effektivsten ausfüllen kann.
Investigating the role of fluorinated amino acids on protein structure and function using simulation
(2018)
Junge Menschen werden im Ordnungswidrigkeitenrecht in erster Linie wie Erwachsene behandelt. Begehen Sie eine Ordnungswidrigkeit, so erhalten sie einen Bußgeldbescheid und werden mit Geldbuße geahndet. Dies verwundert zunächst, denkt man an das ausdifferenzierte System der jugendstrafrechtlichen Sanktionen. Dahinter steckt jedoch die bewusste Entscheidung des Gesetzgebers, die Rechtsanwendung zu vereinfachen und zu vereinheitlichen. Bei näherem Hinsehen entdeckt man aber, dass der Gesetzgeber dem Rechtsanwender durch die Hintertür des Vollstreckungsrechts doch jugendgemäße Sanktionen an die Hand gibt. Ausgehend von diesen Eigentümlichkeiten des Ordnungswidrigkeitenrechts arbeitet die Untersuchung umfassend auf, mit welchen Sanktionen junge Menschen im Ordnungswidrigkeitenrecht konfrontiert werden und ob dies verfassungsrechtlich beanstandungsfrei ist. Die Arbeit plädiert schließlich dafür, das Ordnungswidrigkeitenrecht jugendgemäß weiterzuentwickeln und zeigt hierfür Ansätze auf.
Alte Kämpfer der NSDAP
(2018)
Als „Alte Kämpfer“ galten im Nationalsozialismus alle Personen, die bereits weit vor 1933 der NSDAP beigetreten waren. Sie wurden bislang überwiegend als soziale Randexistenzen und Verlierer der Machtergreifung beschrieben. Anja Stanciu zeigt in ihrer Studie am Beispiel der Berliner NSDAP-Stadtverordneten und –Kreisleiter nun, dass etliche Altparteimitglieder nicht nur Wegbereiter, sondern auch wichtige Mitgestalter der NS-Diktatur waren und zur lokalen NS-Funktionselite gehörten. Untersucht werden die Lebensläufe und Netzwerke dieser Männer zwischen 1926 und 1949. Dabei geht es vor allem um die Frage, wie die Karrieren der „Alten Kämpfer“ und die politische Mobilisierung der Stadtgesellschaft einander bedingten.
Interactional linguistics
(2018)
The first textbook dedicated to interactional linguistics, focusing on linguistic analyses of conversational phenomena, this introduction provides an overview of the theory and methodology of interactional linguistics. Reviewing recent findings on linguistic practices used in turn construction and turn taking, repair, action formation, ascription, and sequence and topic organization, the book examines the way that linguistic units of varying size - sentences, clauses, phrases, clause combinations, and particles - are mobilized for the implementation of specific actions in talk-in-interaction. A final chapter discusses the implications of an interactional perspective for our understanding of language as well as its variation, diversity, and universality. Supplementary online chapters explore additional topics such as the linguistic organization of preference, stance, footing, and storytelling, as well as the use of prosody and phonetics, and further practices with language. Featuring summary boxes and transcripts from recordings of everyday conversation, this is an essential resource for advanced undergraduate and postgraduate courses on language in social interaction.
Den Inhalt eines Vertrags müssen die Parteien nicht selbst, sie können ihn kraft der ihnen zugewiesenen Privatautonomie durch einen Dritten vervollständigen oder anpassen lassen. Dieser Mechanismus lässt sich zu einer alternativen Streitbeilegungsmethode ausbauen, der »Vertragsarbitrage«. Der Begriff Vertragsarbitrage umfasst die in der Praxis weit verbreiteten »Schiedsgutachten« und »Dispute Adjudication Boards«, ist aber umfassender zu verstehen. Die Bezeichnung soll aufzeigen, dass neben der im Prozessrecht geregelten Schiedsgerichtsbarkeit eine im materiellem Recht verwurzelte alternative Streitbeilegungsmethode existiert, die ebenfalls zu verbindlichen Entscheidungen führt.
Über die Untersuchung des deutschen Rechts hinaus wird die Ausgestaltung von Vertragsarbitrageverfahren im englischen und französischem Recht untersucht. Die so nachgewiesenen Unterschiede der Rechtsordnungen führen zu der sodann untersuchten Frage des anwendbaren Rechts.
Der organisierte Fall
(2018)
Stefanie Büchner untersucht in ihrer qualitativ-explorativen Studie die Fallbearbeitung in drei Jugendämtern. Sie zeigt, dass sich die Bearbeitung von Fällen nur unzureichend verstehen lässt, wenn man Organisationen primär als Rahmen begreift oder auf ihre formale Logik reduziert. Vielmehr strukturieren Organisationen als soziale Systeme Fallbearbeitung modular. Fünf Module der Strukturierung stehen im Zentrum der Untersuchung: Wie werden Fälle arbeitsteilig bearbeitet und wie schlägt sich Organisation in der Zusammenarbeit mit Klientinnen und Klienten nieder? Wie lässt sich die unterschiedliche Relevanz von Standards beschreiben? Worin besteht die Herausforderung für Jugendämter, Hilfe und Eingriff zu verantworten und was dokumentiert sich in Dokumentation? Für die Beantwortung dieser Fragen plädiert die Autorin für ein komplexes, allgemeines und spezifisches Verständnis von Organisationen im Feld sozialer Hilfe.