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Two well-defined amphiphilic tetra-arm star block copolymers with a poly(ε-caprolactone) core and poly(ethylene glycol) arms were prepared by a hetero-complementary linkage reaction and studied with respect to their solution behavior in water. more...

Serving as a clergyperson is a highly variable profession and in recent decades, the role has evolved and expanded even further. Consequently, the demands have increased and with it the risk for stress-related ill-health and absenteeism. The aim of the current study was to evaluate, in a larger sample of Swedish clergy (N = 871), two possible antecedents of burnout, namely prosocialness and relational-interdependent self-construal. A further aim was to explore potential gender differences in the investigated associations. The direct and indirect relationships of prosocialness and relational-interdependent self-construal to two dimensions of burnout, exhaustion, and disengagement were investigated in a structural equation-modelling framework. The results showed that clergy who reported higher prosocialness experienced more stress in their work, in terms of both quantitative and emotional demands, which in turn was associated with higher levels of exhaustion and disengagement. But prosocialness was also found to be directly associated with lower levels of disengagement, as well as indirectly associated with higher levels of role clarity. However, no direct or indirect associations were found between relational-interdependent self-construal and any dimension of burnout. Regarding gender differences, female clergy reported higher levels of prosocialness and job demands, less role clarity, and in turn more exhaustion compared to male clergy. This indicated a more stressful situation for female clergy. Our study contributes new insights into the role that personality plays in different dimensions of burnout in clergy, as well as insights into an understanding of gender differences in burnout among clergy. more...

This study investigated the effects of gender, personality (prosocialness, relational-interdependent self-construal, and brooding), job demands, affective work rumination, and personal-to-work conf... more...

In this extended special feature to celebrate the 35th anniversary edition of LCGC Europe, leading figures from the separation science community explore contemporary trends in separation science and identify possible future developments. more...

Stimuli-responsive hydrogels have a wide range of potential applications in microfluidics, which has drawn great attention. Double cross-linked hydrogels are very well suited for this application as they offer both stability and the required responsive behavior. Here, we report the integration of poly(N-isopropylacrylamide) (PNiPAAm) hydrogel with a permanent cross-linker (N,N′-methylenebisacrylamide, BIS) and a redox responsive reversible cross-linker (N,N′-bis(acryloyl)cystamine, BAC) into a microfluidic device through photopolymerization. Cleavage and re-formation of disulfide bonds introduced by BAC changed the cross-linking densities of the hydrogel dots, making them swell or shrink. Rheological measurements allowed for selecting hydrogels that withstand long-term shear forces present in microfluidic devices under continuous flow. Once implemented, the thiol-disulfide exchange allowed the hydrogel dots to successfully capture and release the protein bovine serum albumin (BSA). BSA was labeled with rhodamine B and functionalized with 2-(2-pyridyldithio)-ethylamine (PDA) to introduce disulfide bonds. The reversible capture and release of the protein reached an efficiency of 83.6% in release rate and could be repeated over 3 cycles within the microfluidic device. These results demonstrate that our redox-responsive hydrogel dots enable the dynamic capture and release of various different functionalized (macro)molecules (e.g., proteins and drugs) and have a great potential to be integrated into a lab-on-a-chip device for detection and/or delivery. more...

Thermal field-flow fractionation (ThFFF) was designed to investigate the retention behavior of a series of dendritic polyethylenes synthesized using a chain walking catalyst (cwPE) with variations ... more...

Thermal field-flow fractionation (ThFFF) was used to characterize the architecture of aromatic-aliphatic polyesters with varying degrees of branching. Thermal diffusion and Soret coefficients (DT and ST, respectively) provide a novel route to polymer architecture analysis. This paper demonstrates an innovative strategy to extract architecture information from the physicochemical separation parameters embedded in ThFFF retention times without explicit separation of linear and branched samples. A Soret contraction factor (g″), defined as the ratio of the ST of a branched polymer to the ST of a molecular weight equivalent linear analogue, is introduced as a metric to indicate degree of branching (DB). This approach circumvents several challenges associated with the analysis of high molar mass polymers with a high degree of branching. The g″ value is shown to be proportional to the degree of branching for linear (DB, 0%), gradually branched (DB more...

Recently developed chain walking (CW) catalysis is an elegant approach to produce materials with controllable structure and properties. However, there is still a lack in understanding of how the reaction mechanism influences the macromolecular structures. In this study, a series of dendritic polyethylenes (PE) synthesized by Pd-α-diimine-complex through CW catalysis (CWPE) is investigated by means of theory and experiment. Thereby, the exceptional ability of in situ tailoring polymer structure by varying synthesis parameters was exploited to tune the branching architecture, which allowed us to establish a precise relationship between synthesis, structure, and solution properties. The systematically produced polymers were characterized by state-of-the-art multidetector separation and neutron scattering experiments as well as atomic force microscopy to access molecular properties of CWPE. On a global scale, the CWPE appear in a worm-like conformation independently on the synthesis conditions. However, severe differences in their contraction factors suggested that CWPE differ substantially in topology. These observations were verified by NMR studies that showed that CWPE possess a constant total number of branches but varying branching distribution. Small angle neutron scattering experiments gave access to structural characteristics from global to segmental scale and revealed the unique heterogeneity of CWPE, which is predominantly based on differences in their dendritic side chains. The experimental data were compared to theoretical CW structures modeled with different reaction-to-walking probabilities. Simple theoretical arguments predict a crossover from dendritic to linear topologies yielding a structural range from purely linear to dendritic chain growth. Yet, comparison of theoretical and empirical scattering curves gave the first evidence that a transition state to worm-like topologies is actually experimentally accessible. This crossover regime is characterized by linear global features and dendritic local substructures contrary to randomly hyperbranched systems. Instead, the obtained CWPE systems have characteristics of disordered dendritic bottle brushes and can be adjusted by the walking rate/reaction probability of the catalyst. more...

The influence of the polymer solubility on the separation efficiency in thermal field-flow fractionation (ThFFF) was investigated for a polymer model system of differently branched chain walking polyethylenes in five different solvents, which were selected depending on their physical parameters. The understanding of polymer thermal diffusion has been elucidated using a revisited approach based on the latest thermal diffusion prediction model by Mes,Kok and Tijssen combined with the Hansen solubility theory. Thereby, a significant improvement in the precision of the thermal diffusion prediction and the separation efficiency has been achieved by implementation of the temperature dependency on Hansen solubility parameters. In addition, we demonstrate a method for validation of the segmental size of polymer chains with varying topology by using the revisited thermal diffusion prediction approach in inverse mode and experimental thermal diffusion data. more...

The impact of electron beam irradiation on thermoplastic polyurethane material was studied for both an aliphatic and an aromatic polyurethane with equal amount of hard and soft segments. Irradiation doses up to 300 kGy at room temperature and at 100 °C were applied. Changes in chemical structure, molar mass and size were assessed using infrared spectroscopy, differential scanning calorimetry, size exclusion chromatography and thermal field flow fractionation. Material alterations were correlated with trends regarding to degradation, crosslinking or branching changes. Thereby, limits of characteri-zation by size exclusion chromatography are addressed and amended by thermal field-flow fractionation studies. In addition, a thermophoretic analysis has been carried out complementary to the portfolio of analytical methods applied in this work. more...

The impact of electron beam irradiation on thermoplastic polyurethane material was studied for both an aliphatic and an aromatic polyurethane with equal amount of hard and soft segments. Irradiation doses up to 300 kGy at room temperature and at 100 °C were applied. Changes in chemical structure, molar mass and size were assessed using infrared spectroscopy, differential scanning calorimetry, size exclusion chromatography and thermal field flow fractionation. Material alterations were correlated with trends regarding to degradation, crosslinking or branching changes. Thereby, limits of characteri-zation by size exclusion chromatography are addressed and amended by thermal field-flow fractionation studies. In addition, a thermophoretic analysis has been carried out complementary to the portfolio of analytical methods applied in this work. more...

Social insurance administrative officers’ decision‐making skills influence their efficiency at work and their general well‐being. At work their tasks are characterised by complexity and a need for order and accountability. Moreover, cases should usually be handled and finalised within the imposed time frames. We investigated skills related to decision‐making success among social insurance officers. In total, 118 administrative officers at the Swedish Social Insurance Agency (66% response rate) responded to questions on scales and measures relating to cognitive‐rational, socio‐emotional and time approach features of decision‐making skill. In addition, they responded to questions on three scales pertaining to outcomes of everyday decisions in terms of subjective everyday difficulties, tendencies to burnout and depressive symptoms. The results showed that cognitive‐rational competence was associated with lower reports of subjective everyday difficulties and depressive symptoms and thereby contributed to the explained variance in decision outcomes. Furthermore, socio‐emotional and time approach features of decision‐making skills contributed to the explanation for subjective everyday difficulties, tendencies to burnout and depressive symptoms. The results corroborate the basic assumption and usefulness of a broad approach in the definition and assessment of decision‐making skills in human service professions in general, and of administrative officers in social insurance agencies in particular. Recommendations for future research and the implications of the results are discussed. more...

The present study investigated how psychosocial safety climate (PSC), job demands (role conflict and work-family conflict), job resources (social support from superiors and social community at work), and assessments for quality of work relate to social workers’ work engagement, job satisfaction, and organizational commitment. The results of the questionnaire study (N = 831) showed that quality of work was strongly related to all three outcomes, whereas PSC was found to be related to social workers’ job satisfaction. The contribution of the study is discussed in relation to understanding the retention of social workers. more...

The impact of electron beam irradiation on thermoplastic polyurethane material was studied for both an aliphatic and an aromatic polyurethane with approximately equal molar amount of hard and soft segments. Irradiation doses up to 300 kGy (kilogray) at room temperature and at 100 °C were applied. Changes in chemical structure, molar mass and size were assessed using infrared spectroscopy, differential scanning calorimetry, size-exclusion chromatography and thermal field-flow fractionation. Material alterations were correlated with trends regarding to degradation, crosslinking or branching changes. Thereby, limits of characterization by size exclusion chromatography are addressed and amended by thermal field-flow fractionation studies. In addition, a thermophoretic analysis has been carried out complementary to the portfolio of analytical methods applied in this work. more...

The non-parabolicity correction of the laminar flow profiles was numerically calculated for fifty-nine solvents. The exact flow profiles were simulated based on sophisticated experimental literature data of dynamic viscosity and thermal conductivity and their dependency on the temperature in between cold wall temperatures of –10 °C up to 120 °C and temperature gradients up to ΔT = 120 K. Based on this computation the polynomial coefficients for the calculation of the non-parabolicity parameter ν is tabulated for each solvent. For this calculation a third-degree polynomial velocity profile was applied, which approximates in a good agreement the exact profile for moderately distorted flow profiles. Instead, for strongly distorted flow profiles a more exact solution with keeping ν as only adjustable parameter is proposed. Additionally, an empirically derived solution is presented to calculate the dimensionless retention parameter λ in fair accuracy directly from retention data. more...

Der Beitrag fokussiert das Phanomen Digitalisierung auf Ebene von Kommunikation und damit einhergehenden Veranderungen, Herausforderungen und Perspektiven fur die Soziale Arbeit und die Beratung. Ausgehend von kommunikationstheoretischen Grundlagen sowie medienpadagogischen Aspekten, werden kritische und potentialversprechende Faktoren digitalisierter Kommunikation fur die Soziale Arbeit generell und die Beratung im speziellen diskutiert. more...

Work-related stress and stress-related ill health are major concerns in modern Western societies. In the European Union, the joint Occupational Safety and Health (OSH) framework obliges employers to ensure the health and safety of workers in every aspect related to work, including psychological safety and health. Against this background, the aim of the present study was to gain a deeper understanding of the cross-cultural validity of the Psychosocial Safety Climate (PSC) instrument as a measure for organizational and managerial commitment to employee psychological health. By integrating findings from cognitive interview studies conducted in Germany and in Sweden, we found participants considered the focus of PSC on managerial and organizational perspectives as an important contribution to workplace surveys. However, we were also able to identify some challenges (e.g., in relation to translation of key concepts, the intended shift of referent, and the use of the intermediate response options) as difficulties in identifying a homogeneous PSC within an organization was also observed to some extent. We can conclude that integrating findings from cognitive interviews conducted in two European countries expands the existing knowledge of the PSC measure. This is achieved by a deeper understanding of problems that might occur when transferring PSC to a different context. The overall findings of the present study corroborate the cross-cultural validity of transferring the PSC measure from an Australian to a European context, and we consider PSC to be a valid and useful framework for targeting psychosocial risks and organizational procedures in a European setting. more...

Emotional demands are an inevitable feature of human services, and suggested to be a defining antecedent for workers' stress and ill health. However, previous research indicate that emotional demands can have a favorably association to certain facets of human service workers' motivation and well-being. Furthermore, recent research report that the effect of emotional demands on workers' health and well-being seem to be contingent on the parallel level of other job demands. Still, initial investigations of interaction effects between emotional demands and other types of job demands have primarily focused on negative outcomes in terms of stress-related concerns and absenteeism. The present study investigated interaction effects between emotional demands and other types of job demands in relation to positive outcomes. In a larger sample of human service workers (social workers more...

Molar mass and end group number of a hyperbranched polyester are significantly increased by its transformation to a pseudodendrimer. Three generations of pseudodendrimers are obtained from hyperbranched aliphatic polyester core by modification with a protected AB*2 monomer. A sequence of protection and deprotection steps leads to OH-terminated pseudodendrimers. NMR studies confirm maximum degree of branching in the first generation, which slightly decreases in the next two generations. Uniform, dense molecular structure formation was confirmed by MD simulation. Further modification to glyco-pseudodendrimers was performed with α-D-mannose leading to high molar masses and dense distribution of sugar units. The interaction of these sugar units with a plant lectin concanavalin A (Con A) was investigated using dynamic light scattering and cryogenic transmission electron microscopy. The protein-interaction studies of the glyco-pseudodendrimers confirm a loose network with Con A. The interaction activity depends on the generation number and modification degree. more...

What distinguishes a competent decision maker and how should the issue of decision quality be approached in a real-life context? These questions were explored in three studies. In Study 1, using a web-based questionnaire and targeting a community sample, we investigated the relationships between objective and subjective indicators of real-life decision-making success. In Study 2 and 3, targeting two different samples of professionals, we explored if the prevalent cognitively oriented definition of decision-making competence could be beneficially expanded by adding aspects of competence in terms of social skills and time-approach. The predictive power for each of these three aspects of decision-making competence was explored for different indicators of real-life decision-making success. Overall, our results suggest that research on decision-making competence would benefit by expanding the definition of competence, by including decision-related abilities in terms of social skills and time-approach. Finally, the results also indicate that individual differences in real-life decision-making success profitably can be approached and measured by different criteria. more...

Einen Text uber die angenommene Zukunft zu formulieren, erscheint nicht nur problematisch, sondern bisweilen manipulativ. Ein Orakel wurde in der Vergangenheit unter anderem dazu genutzt, bestehende oder gewunschte Strukturen zu festigen bzw. zu forcieren. Auch heute kann ein Ausblick auf die Zukunft nicht erfolgen, ohne seine eigene Position und seine subjektiven Wunsche darin auszudrucken. more...