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Michael Lipsky states through his theory of street-level bureaucracy that teachers, among other street-level occupations, often work under a heavy workload due to parameters built into their occupations characteristics and limited resources. Lipsky says that street-level bureaucrats therefor under the influence of their works natural discretion tend to use client-processing strategies to lighten the pressure to make their work situation bearable. Teachers in Sweden is an occupational group that has an important societal function in educating children, teenagers and young adults for their future social lives. At the same time as they work under a heavy workload. This essay aims to see if teachers in Sweden uses the three client-processing strategies tension between capability and objectives, private goal definition and defense against discretion to modify their work and students, to make their work situation more bearable. This is tested quantitively through Pearsons chi2 test of independence and regression analysis. The conclusion is that even though a tendency towards the use of client-processing strategies can be seen in the results, one cannot conclude that this is actually the case and that further studies has to be done to be able to give a more accurate response to the question.

<p>  </p> <p>Plastics play crucial rules in almost every aspect of life. Unique properties of plastics like chemical and light resistant, strong, moldable, and low cost make plastic materials useful in many aspects of our global society. However, largely relying on feedstock resources like fossil fuels, plastics production is not sustainable. Thus, plastic recycling could be an efficient alternative to save feedstock resources as well as to reduce production cost.</p> <p>Recently, a series of polymer materials synthesized via topochemical polymerization are considered as strong candidates for next generation recyclable plastics. It is well-known that topochemical polymerization has high efficiency and environment-friendly features, such as solvent-free and catalyst-free reaction conditions, high reaction yield without side reactions, and atom economy. Yet, there exist few studies on depolymerizing and recycling those polymers. A unique topochemically polymerizable polyindenedione derivative [2,2'-Bi-1H-indene]-1,1'-dione-3,3'-diyl dialkylcarboxylate (polyBIT) with rapid and quantitative depolymerization was discovered via breakage of elongated carbon-carbon (C-C) bonds with bond length of 1.57∼1.63 Å. The elongated C-C bonds have been proven theoretically and experimentally to have significantly lower bond dissociation energies than normal C-C bonds, and it is the major driving force to depolymerize polyBIT polymer single crystals. </p> <p>Different from most traditional polymers that can be dissolved or melt processed, topochemical polymer single crystals are not soluble in most common solvents due to their highly crystalline and ordered nature. This unique feature inhibited topochemical polymer crystals from practical applications. To convert needle-like polyBIT crystals into useful forms, I developed an ultrasonication method to break large polymer crystals into small fibers that can be uniformly suspended in organic solvents. Followed by vacuum filtration and heat press, polyBIT crystals can be processed into robust and freestanding polymer thin films. The processed thin films presented reasonable mechanical properties with Young’s modulus of over 600MPa and are stable under harsh conditions.</p> <p>Topochemical polymerization reactions require specific monomer packings before applying external stimuli, and a small change in monomer structure may completely alter the reactivity. Therefore, functionalizing monomer structures for topochemical reactions is quite challenging. In the polyBIT system, we attempted to functionalize BIT monomer with several linear and branched side chains. After preparing monomer crystals, only needle-like 1D monomers can be photopolymerized, while plate-like 2D monomer crystals became photostable. Introducing heteroatoms (such as oxygen, sulfur, bromine, chlorine) can induce different non-bonding interactions and interactions, which combined can push monomers away from one another to make them unreactive. Introducing branched side chains will also change the distances between two BIT monomers and leads to unreactive crystals when the branched side chain is too bulky (such as when tertbutyl group is on the end of side chain). Functionalizing side chains for polyBIT crystals can further tune the mechanical properties of the crystals: swapping end methyl group with a simple bromine atom can induce multiple intermolecular and interchain interaction including weak hydrogen bonding and C−H···Br interactions. These interactions bind all the polymer chains together to provide a strong 1D polymer fiber with elastic modulus over 10.6 GPa. These results suggest that the crystalline polymers synthesized from simple photochemistry and without expensive catalysts are promising for practical applications with complete materials circularity and wide range of structural and mechanical turnabilities.</p>

Die visuelle Enkodierung emotionaler Gesichtsausdrücke stellt bisher ein Rätsel dar. Ziel der vorliegenden Dissertation war es daher, durch die Untersuchung von Blickbewegungen und ihrer Funktionalität für das Erkennen von Gesichtsausdrücken, neue Erkenntnisse zu den zugrundeliegenden Prozessen zu liefern. In vier Blickbewegungsexperimenten, in denen Probanden ärgerliche, angeekelte, fröhliche, traurige und neutrale Gesichtsausdrücke in statischer und dynamischer Darbietung kategorisieren sollten, wurde untersucht, ob allgemeine Strategien der Gesichterverarbeitung bereits auf der Ebene der visuellen Enkodierung anhand spezifischer Blickbewegungsmuster zu identifizieren sind und ob Unterschiede bei der initialen Aufnahme visueller Information als Folge unterschiedlicher Fixationspositionen das Erkennen von Gesichtsausdrücken beeinflussen. Die Ergebnisse zeigten, dass für statische Gesichtsausdrücke nur sehr wenige Fixationen gemacht werden, die hauptsächlich auf das Zentrum des Gesichts und auf emotionsspezifische, diagnostische Gesichtsmerkmale gerichtet sind, was eine kombiniert holistisch-merkmalsorientierte Enkodierungsstrategie nahelegt. Für weniger intensive und dynamische Gesichtsausdrücke deuten die Ergebnisse auf eine stärker konfigurale Enkodierungsstrategie mit mehreren Fixationen zu einer größeren Anzahl unterschiedlicher Gesichtsmerkmale hin. Darüber hinaus waren Blickbewegungsunterschiede relevant für die Emotionserkennung. Die Fixation diagnostischer Gesichtsmerkmale beschleunigte das Erkennen statischer Gesichtsausdrücke. Für das Erkennen dynamischer Gesichtsausdrücke war hingegen eine zentrale Fixationsposition vorteilhaft, vermutlich durch die Förderung von holistischer Gesichterverarbeitung und Veränderungserkennung. Insgesamt zeigte sich, dass allgemeine Strategien der Gesichterverarbeitung bereits auf der Ebene der visuellen Enkodierung identifizierbar sind und dass Unterschiede in diesen frühen Prozessen die Erkennungsleistung beeinflussen. / Processes that underlie the visual encoding of facial expressions still pose a conundrum. Therefore, this dissertation set out to provide new insights into these processes by investigating gaze behaviour and its functional role during the recognition of facial expressions. Four experimental studies were conducted to examine whether general face processing strategies are already reflected on the visual encoding stage of facial expression recognition indicated by specific fixation patterns and whether differences at the initial uptake of visual information as a consequence of varying fixation positions affect facial expression recognition. Gaze behaviour was recorded while participants were asked to categorise angry, disgusted, happy, sad, and neutral facial expressions in static and dynamic displays. Results revealed that gaze behaviour for static facial expressions was characterised by only a few fixations mainly directed to the centre and to expression-specific diagnostic facial features of the face, suggesting a combined holistic and featural encoding strategy. For less intense and dynamic facial expressions, results indicated a more configural encoding strategy with multiple fixations to a greater number of different facial features. In addition, differences in gaze strategy were relevant for facial expression recognition. Fixating diagnostic facial features accelerated the recognition of static facial expressions. In contrast, a central fixation position was beneficial for recognizing dynamic facial expressions, presumably by facilitating holistic face processing and change detection. Overall, findings demonstrated that general face processing strategies are already reflected on the visual encoding stage of facial expression recognition and that variations in these early processes affect recognition performance.