Spectroscopic studies on the interaction of bilirubin with symmetrical alkyl diamines

The interactions of symmetrical alkyldiamines with bilirubin-IX α have been examined in dichloromethane and dioxane solutions, by visible region difference spectroscopy and florescence methods. In dioxane solutions a clear difference is observed between the complexes of the shorter chain diamines (number of spacer methylene groups (n ≤ 4) ) and the longer chain diamines (n ≥ 6) . The variations in spectral features with diamine chain length are less pronounced in dichloromethane. The spectroscopic results are consistent with the occurrence of distinct bilirubin conformations depending upon the solvent and the geometry of the interacting receptor. Based on molecular modelling two conformations are proposed. A 'ridge-tile' model similar to that observed in crystals is favoured for binding to the longer diamines, while a 'quasi-cyclic' structure is preferred for interaction with the short chain diamines

Trust Over Time in Exchange Relationships: Meta-Analysis and Theory

A common premise in prior research is that trust increases over time in relationships. Through a meta-analysis of 39 studies, we find that the bivariate correlation between trust and relationship duration (1) is on average positive and small, and (2) varies significantly across studies indicating the presence of unobserved moderators. We therefore build a theoretical framework to specify four different mechanisms—initial bias correction, change in relationship value, identification, and trust-based selection—that may affect the development of trust. We then argue that the relative strength of these mechanisms should influence whether trust increases, remains constant, or decreases over time

Repeated Interactions and Contractual Detail: Identifying the Learning Effect

Organizations interacting repeatedly on similar transactions may learn from prior experiences, allowing contracts to be specified in greater detail. In this study, we analyze the conditions under which this learning effect is most likely to manifest itself. We do this by focusing on different parts of a contract as well as differences across transacting parties. Using a survey of information technology procurement contracts from 788 Dutch small- and medium-sized enterprises, we show that the learning effect is stronger for technical than for legal detail in contracts and is stronger for firms with information technology expertise than for firms without such expertise

Organizational cultural strength as the negative cross-entropy of mindshare: a measure based on descriptive text

The strength of an organization’s culture is an important property that may have implications for organizational structure, performance, diversity, and inclusion, independent of its content. However, progress on conceptualizing and measuring cultural strength has been restricted so far. We propose a novel measure of an organization’s cultural strength as the negative average cross-entropy of its members’ mindshare distributions, defined on a support comprising a set of firm-specific cultural elements. Using descriptive text data produced by 2.9 million individuals in about 95 thousand US firms from the employee review website Glassdoor.com, we calculate our measure of organizational cultural strength using topic modeling and show that it behaves as theoretically expected: older, smaller, and more geographically concentrated firms have stronger organizational cultures. We also note some intriguing associations between organizational cultural strength, role differentiation, and gender imbalance within firms. Finally, we discuss opportunities for using this new measure to understand how organizations work more generally

Organizational adaptation to interdependence shifts: The role of integrator structures

RESEARCH SUMMARY: We investigate how organizational adaptation to interdependence shifts is influenced by “integrators.” These are formally mandated managerial roles meant to promote coordination across specialized but interdependent organizational subunits, yet they do so without relying on formal authority. While much has been learned about how integrators promote steady-state coordination within a known pattern of interdependence, less is known about their impact on organizational adaptation when the pattern of interdependence itself is unknown. We discuss mechanisms by which integrators may nonetheless aid organizational adaptation and learning processes in such situations, and test our hypotheses in the context of a regulatory change that affected the in vitro fertilization (IVF) clinics sector in the United Kingdom using a differences-in-differences design. MANAGERIAL sUMMARY: Organizational structure can influence how an organization adapts to change. We investigate how a regulatory change in the provision of fertility treatments in the United Kingdom forced clinics to change their workflows, and whether the presence of integrator roles enabled clinics to adapt to these changes. It is well known that integrator roles in general are valuable in coordinating across specialized organizational units, but this research points to the surprising implication that their value may persist even when the workflow being coordinated changes suddenly, in ways that nobody necessarily comprehends. Our research highlights the fact that even in an intensively science-based work context, the “technology of organizing” can have a significant role in shaping organizational performance

The Deafness-Associated Mitochondrial DNA Mutation at Position 7445, Which Affects tRNASer(UCN) Precursor Processing, Has Long-Range Effects on NADH Dehydrogenase Subunit ND6 Gene Expression

The pathogenetic mechanism of the deafness-associated mitochondrial DNA (mtDNA) T7445C mutation has been investigated in several lymphoblastoid cell lines from members of a New Zealand pedigree exhibiting the mutation in homoplasmic form and from control individuals. We show here that the mutation flanks the 3' end of the tRNASer(UCN) gene sequence and affects the rate but not the sites of processing of the tRNA precursor. This causes an average reduction of ~70% in the tRNASer(UCN) level and a decrease of ~45% in protein synthesis rate in the cell lines analyzed. The data show a sharp threshold in the capacity of tRNASer(UCN) to support the wild-type protein synthesis rate, which corresponds to ~40% of the control level of this tRNA. Strikingly, a 7445 mutation-associated marked reduction has been observed in the level of the mRNA for the NADH dehydrogenase (complex I) ND6 subunit gene, which is located ~7 kbp upstream and is cotranscribed with the tRNASer(UCN) gene, with strong evidence pointing to a mechanistic link with the tRNA precursor processing defect. Such reduction significantly affects the rate of synthesis of the ND6 subunit and plays a determinant role in the deafness-associated respiratory phenotype of the mutant cell lines. In particular, it accounts for their specific, very significant decrease in glutamate- or malate-dependent O2 consumption. Furthermore, several homoplasmic mtDNA mutations affecting subunits of NADH dehydrogenase may play a synergistic role in the establishment of the respiratory phenotype of the mutant cells

The role of integrators in organizational adaptation to interdependence shocks: Evidence from fertility clinics

This paper empirically investigates how organizational adaptation to interdependence shocks is influenced by “integrators”. These are formally mandated managerial roles meant to promote coordination across specialized but interdependent organizational sub-units without relying on formal authority. While much has been learned about how integrators promote steady state coordination within a known pattern of interdependence, less is known about their impact on organizational adaptation when the pattern of interdependence itself changes. We discuss mechanisms by which integrators may also be useful in such situations, and test our hypotheses in the context of a regulatory shock that affected the IVF clinics sector in the UK

Trust and Governance: Untangling A Tangled Web

Using a simple but general formalization, we state the conditions under which one might expect a negative or positive relationship between preexisting trust and governance complexity, and whether crowding out or complementarity arguments are necessary for such outcomes. Our analysis provides a platform for simple but rigorous analysis of other possible relationships between trust and governance and also suggests that the debate about the relationship between governance and trust could be fruitfully redirected through greater attention to the analytical structure of the arguments

Human-AI Ensembles: When Can They Work?

An “ensemble” approach to decision-making involves aggregating the results from different decision makers solving the same problem (i.e., a division of labor without specialization). We draw on the literatures on machine learning-based Artificial Intelligence (AI) as well as on human decision-making to propose conditions under which human-AI ensembles can be useful. We argue that human and AI-based algorithmic decision-making can be usefully ensembled even when neither has a clear advantage over the other in terms of predictive accuracy, and even if neither alone can attain satisfactory accuracy in absolute terms. Many managerial decisions have these attributes, and collaboration between humans and AI is usually ruled out in such contexts because the conditions for specialization are not met. However, we propose that human-AI collaboration through ensembling is still a possibility under the conditions we identify