Reaction-Diffusion Degradation Model for Delayed Erosion of Cross-Linked Polyanhydride Biomaterials

We develop a theoretical model to explain the long induction interval of water intake that precedes the onset of erosion due to degradation caused by hydrolysis in the recently synthesized and studied cross-linked polyanhydrides. Various kinetic mechanisms are incorporated in the model in an attempt to explain the experimental data for the mass loss profile. Our key finding is that the observed long induction interval is attributable to the nonlinear dependence of the degradation rate constants on the local water concentration, which essentially amounts to the breakdown of the standard rate-equation approach, potential causes for which are then discussed. Our theoretical results offer physical insights into which microscopic studies will be required to supplement the presently available macroscopic mass-loss data in order to fully understand the origin of the observed behavior

Integrating Problem Solvers from Analogous Markets in New Product Ideation

Who provides better inputs to new product ideation tasks: problem solvers with expertise in the area for which new products are to be developed, or problem solvers from "analogous" markets that are distant but share an analogous problem or need? Conventional wisdom appears to suggest that target market expertise is indispensable, which is why most managers searching for new ideas tend to stay within their own market context even when they do search outside their firms' boundaries. However, in a unique symmetric experiment that isolates the effect of market origin, we find evidence for the opposite: Although solutions provided by problem solvers from analogous markets show lower potential for immediate use, they demonstrate substantially higher levels of novelty. Also compared to established novelty drivers, this effect appears highly relevant from a managerial perspective: we find that including problem solvers from analogous markets vs. the target market accounts for almost two thirds of the well-known effect of involving lead users instead of average problem solvers. This effect is further amplified when the analogous distance between the markets increases, i.e., when searching in far vs. near analogous markets. Finally, results indicate that the analogous market effect is particularly strong in the upper tail of the novelty distribution, which again underscores the effect's practical importance. All this suggests that it might pay to systematically search across firm-external sources of innovation that were formerly out of scope for most managers. (authors' abstract

Exploring the Dynamic Relationship of Transformational Leadership Behavior and Leader Well-Being : a Three-Wave Cross-Lagged Panel Study

Leadership behavior is associated with leader well-being. Yet, existing research, with the majority representing cross-sectional studies, limits our understanding of the association over time, potential mediating mechanisms, and potential reciprocal relations. Based on Conservation of Resources (COR) theory, we test between- and within-person relationships between transformational leadership and leader vigor as well as emotional exhaustion over time. In addition, we include leaders’ occupational self-efficacy, information exchange with followers, and meaning of work as mediators. 132 leaders participated in a fully cross-lagged study across three consecutive weeks. We analyzed the data with a random intercept cross-lagged panel model (RI-CLPM) that allows separating the within- and between-person variance in our variables. At the between-person level, transformational leadership was positively related to vigor, occupational self-efficacy, information exchange, and meaning of work. At the within-person level, there were no lagged associations of transformational leadership and well-being, but a positive lagged effect of vigor in one week on information exchange and meaning of work in the next week. Within one week, transformational leadership was related to occupational self-efficacy, meaning of work, and vigor (positive, respectively) and to emotional exhaustion (negative) within persons. In line with COR theory, we discuss transformational leadership as a resource for leaders associated with greater well-being for leaders. Our study contributes to the literature on dynamic leadership behavior and the mechanisms between leadership and leader well-bein

What Does Leadership Do to the Leader? : Using a Pattern-Oriented Approach to Investigate the Association between Daily Leadership Profiles and Daily Leader Well-Being

Leader behavior can vary daily, and leaders face multiple demands and problems in one day. Therefore, studying how leader behaviors interplay on the day-level (i.e., daily leadership profiles) is essential. Building on conservation of resources theory as a meta-theory, we investigated which daily leadership profiles exist and whether profile membership changes across one week. Additionally, we examined whether the leadership profiles are differentially related to leaders' daily well-being (i.e., emotional exhaustion, positive and negative affect), mediated by their daily experienced thriving and time pressure. In a diary study over five workdays (N = 289 leaders), we found three qualitatively different daily leadership profiles: one dominated by passive behaviors (passive), one dominated by transformational and contingent reward behaviors (transformational-rewarding), and one with elevated transformational and all transactional behaviors (comprehensive). The transformational-rewarding and the comprehensive profile showed greater stability across the week than the passive profile. Days in the transformational-rewarding profile were most beneficial for leaders' well-being. In contrast, days in the comprehensive profile seemed to be a double-edged sword for leaders, as indicated by higher experienced thriving and positive affect and simultaneously enhanced experienced time pressure, emotional exhaustion, and negative affect. Taken together, we illuminate the interplay of leadership behaviors on the day-level and the differential associations with leaders' well-being

Harnessing the Creative Potential of Consumers: Money, Participation and Creativity in Idea Crowdsourcing

Given the growing importance of innovation and consumer engagement, many firms are strongly interested in finding ways to encourage their consumers to generate creative new product ideas for them in their crowdsourcing initiatives. To that end, managers often use monetary rewards – one of the most commonly used managerial tools to stimulate desired behaviors. A critical question in this respect is whether the use of monetary rewards is effective in stimulating creativity and, if so, how large those rewards should be. This study aims to answer these questions. The results of an experiment suggest that introducing monetary rewards does not contribute to the number of new product ideas generated by a single consumer or the novelty of his/her ideas, and when the reward is relatively small it can even be harmful. Monetary rewards, however, are effective in encouraging widespread participation in crowdsourcing initiatives and improving the appropriateness of the new product ideas. As a whole, these findings take us a step further toward better understanding the motivational mechanisms of consumer creativity in new product ideation

The value of scientific knowledge dissemination for scientists:A value capture perspective

Scientific knowledge dissemination is necessary to collaboratively develop solutions to today’s challenges among scientific, public, and commercial actors. Building on this, recent concepts (e.g., Third Mission) discuss the role and value of different dissemination mechanisms for increasing societal impact. However, the value individual scientists receive in exchange for disseminating knowledge differs across these mechanisms, which, consequently, affects their selection. So far, value capture mechanisms have mainly been described as appropriating monetary rewards in exchange for scientists’ knowledge (e.g., patenting). However, most knowledge dissemination activities in science do not directly result in capturing monetary value (e.g., social engagement). By taking a value capture perspective, this article conceptualizes and explores how individual scientists capture value from disseminating their knowledge. Results from our qualitative study indicate that scientists’ value capture consists of a measureable objective part (e.g., career promotion) and a still unconsidered subjective part (e.g., social recognition), which is perceived as valuable due to scientists’ needs. By advancing our understanding of value capture in science, scientists’ selection of dissemination mechanisms can be incentivized to increase both the value captured by themselves and society. Hence, policy makers and university managers can contribute to overcoming institutional and ecosystem barriers and foster scientists’ engagement with society

A Miniaturized Ligand Binding Assay for EGFR

In order to study receptor abundance and its function in solutions or in homogenates from clinical specimen, methods such as sandwich or radioimmunoassays are most commonly employed. For the determination of epidermal growth factor receptor (EGFR), we describe the development of a miniaturized bead-based ligand binding assay using its ligand EGF as immobilized capture reagent. This assay was used to analyze lysates from cell lines, and the ligand-bound EGFR was detected using an EGFR-specific antibody combined with a fluorescence-based reporter system. In a proof-of concept study with lysates from breast biopsies, the assay allowed to classify breast cancer samples in accordance to clinically the relevant EGFR cut-off level. The study suggests that such a ligand binding receptor assay could become an integral part of protein profiling procedures to provide additional information about receptor functionality in addition to its abundance

Multi-disciplinary perspectives on citizen science – synthesizing five “paradigms” of citizen involvement

Research on Open Innovation in Science (OIS) investigates how open and collaborative practices influence the scientific and societal impact of research. Since 2019, the OIS Research Conference has brought together scholars and practitioners from diverse backgrounds to discuss OIS research and case examples. In this meeting report, we describe four session formats that have allowed our multi-disciplinary community to have productive discussions around opportunities and challenges related to citizen involvement in research. However, these sessions also highlighted the need for a better understanding of the underlying rationales of citizen involvement in an increasingly diverse project landscape. Building on the discussions at the 2023 and prior editions of the conference, we outline a conceptual framework of five crowd paradigms and present an associated tool that help understand how citizen involvement in particular projects can help advance science. We illustrate this tool using cases presented at the 2023 conference and discuss how it can facilitate discussions at future conferences as well as guide future research and practice in citizen science

Proteomic analysis of hepatic effects of phenobarbital in mice with humanized liver

Activation of the constitutive androstane receptor (CAR) may induce adaptive but also adverse effects in rodent liver, including the induction of drug-metabolizing enzymes, transient hepatocellular proliferation, and promotion of liver tumor growth. Human relevance of CAR-related adverse hepatic effects is controversially debated. Here, we used the chimeric FRG-KO mouse model with livers largely repopulated by human hepatocytes, in order to study human hepatocytes and their response to treatment with the model CAR activator phenobarbital (PB) in vivo. Mice received an intraperitoneal injection with 50 mg/kg body weight PB or saline, and were sacrificed after 72–144 h. Non-repopulated FRG-KO mice were used as additional control. Comprehensive proteomics datasets were generated by merging data obtained by targeted as well as non-targeted proteomics approaches. For the first time, a novel proteomics workflow was established to comparatively analyze the effects of PB on human and murine proteins within one sample. Analysis of merged proteome data sets and bioinformatics data mining revealed comparable responses in murine and human hepatocytes with respect to nuclear receptor activation and induction of xenobiotic metabolism. By contrast, activation of MYC, a key regulator of proliferation, was predicted only for mouse but not human hepatocytes. Analyses of 5-bromo-2′-deoxyuridine incorporation confirmed this finding. In summary, this study for the first time presents a comprehensive proteomic analysis of CAR-dependent effects in human and mouse hepatocytes from humanized FRG-KO mice. The data support the hypothesis that PB does induce adaptive metabolic responses, but not hepatocellular proliferation in human hepatocytes in vivo.publishedVersio