459 research outputs found
Reproducibility and optimization in capillary electrophoresis
It is well known that poor quantitative reproducibility substantially limits the practical implementation of capillary electrophoresis (CE) separations in chemical analysis. The principal sources of variance in observed peak areas are irreproducible flow rate which influences on-column detector response, and inconsistent injection volume or amount. In addition, current efforts in our laboratory to assess sources of quantitative variance for separations of dansylated amino acids using an automated CE system are presented and related when appropriate to the body of existing knowledge on this important topic. A comparison of different injection methods, the effect of random changes in electroosmotic flow (EOF), and choice of certain peak integration parameters in terms of peak area reproducibility are presented. An approach is presented to optimize conditions for capillary electrophoresis separations of multi-analyte enantiomeric-pairs (D- and LDansyl (Dns)-amino acids) that involves the rational use of combinations of cyclodextrins (CDs) as enantio-selective running buffer additives. Migration data is experimentally obtained for a range of concentrations for native CDs used individually and employed to determine inclusion constants for the Dns-amino acids of interest. Simplex methods are then employed for the first time to optimize conditions for the separation of amino acid enantiomers. The validity of this approach is demonstrated for separations of five Dns-amino acids enantiomers using y- and f3-CDs at various concentrations. Extending the dual-CD approach to other CDs and increasing the number of CDs beyond two should be possible. To this end, preliminary experiments are performed by using several available single-isomer, derivatized CDs (individually) to determine if they have potential for further studies. It was found that molecular mechanics modeling is useful in interpreting those cases where low inclusion constants likely contributed to the ineffectiveness of the CDs. Finally, it is important in CE to have solute identification capabilities for unknown mixtures and because of the variable electroosmotic flow, which causes irreproducible migration times. A counter flow arrangement for surface enhanced Raman Spectroscopy was developed for this purpose and colloidal silver is added externally since it can affect efficiency when inserted in the running buffer
Yearbook of the Maimonides Centre for Advanced Studies 2016
The Yearbook mirrors the annual activities of staff and visiting fellows of the Maimonides Centre and reports on symposia, workshops, and lectures taking place at the Centre. Although aimed at a wider audience, the yearbook also contains academic articles and book reviews on scepticism in Judaism and scepticism in general. Staff, visiting fellows, and other international scholars are invited to contribute
The Role of Internationalization Strategy in Fostering Innovation: An Empirical Study Using Machine Learning Technique
In todayâs highly dynamic global market, firms increasingly conduct R&D internationally to enhance their innovation and competitiveness. We analyze the relationship between firm internationalization strategy and innovation performance. We argue that the relationship is inverse U-shaped, due to concave returns and convex costs of firm internationalization regarding innovation performance. We test our hypothesis using a novel machine-learning technique and develop a dictionary on internationalization, based on the most-cited papers on firm internationalization. We then apply this dictionary to firmsâ 10-K annual reports to obtain a unique score of each firmâs internationalization strategy and use panel data econometrics to analyze the relationship with innovation performance. The results support the hypothesis of an inverted U-shape relationship between firmsâ internationalization strategy and innovation performance. Further tests substantiate the findings. Our study contributes to the literature on firm internationalization and firm innovation by identifying a trade-off in benefits and costs of firm internationalization
From Feelings to Funding: The Moderating Role of Category Membership in Crowdfunding Participation
This study investigates the impact of emotions conveyed in crowdfunding campaigns on the commitment of backers. Based on language expectancy theory and research on emotional psychology, we propose the effect of emotions depends on campaign category membership and varies between social and commercial crowdfunding campaigns. Empirical analyses of 12,862 Indiegogo campaigns using EmoRoBERTa, a pre-trained neural network algorithm specifically designed to identify emotions, reveal that gratitude and optimism have opposite effects on crowdfunding participation for social and commercial entrepreneurs. In particular, optimism is positively associated with backer participation in social and negatively in commercial campaigns. Counterintuitively, gratitude is positively associated with backer participation in commercial but negatively in social campaigns. Contrasting our analysis, we further examine the link between a factual, neutral tone and crowdfunding participation. Interestingly, a neutral tone has a positive relationship with crowdfunding participation in commercial campaigns. The association reverses for social campaigns
Diskontinuierliche Erwerbskarrieren und Berufswechsel in den 1990ern : Strukturmuster und biografische Umgangsweisen betrieblich ausgebildeter FachkrÀfte (Interrupted employment histories and change of occupation in the 1990s : structural pattern and biographical behaviour of qualified employees trained in companies)
"A widespread thesis assumes that as a consequence of the socio-economic change in industrial societies firstly the 'normal life' centred around gainful employment is disappearing and secondly the occupation is losing its institutional stability and thus its significance for employment and as an orientational quantity in the shaping of biographies. Even if there is agreement that employment is changing its shape, there has not yet been sufficient empirical clarification as to how far these processes of change have progressed or how strongly they are reflected in biographies. The paper deals with these consequences of the change for biographies as well as subjects and organisation methods related to occupational biography. On the basis of a quantitative longitudinal study with a cohort of young skilled employees whose occupational development was followed from completion of training in 1989/90 until approx. eight years later, and taking as an example six of the most common training occupations with different labour market prospects, it is shown that neither interrupted occupational histories nor changes of occupation are exceptional phenomena but that they have become normality. However, discontinuity is not to be equated per se with instability or precariousness, and to a certain extent occupational histories and changes of occupation continue to be influenced by the occupation itself. On the basis of qualitative longitudinal data obtained with a sub-sample of the quantitative panel, discontinuous employment histories and changes of occupation are examined from a subject- related viewpoint. Here it becomes clear firstly that also the different forms of interpretation and structure of discontinuity are related in some cases to the occupation and that for young adults with discontinuous employment histories employment retains a high level of subjective relevance. Secondly it emerges that a change of occupation is in most cases preceded by the creation of a new occupational orientation with the result that a high subjective connective force is attached to the occupation. According to the conclusion, the occupational concept continues to play an important role as an explanatory potential for employment histories, and for young adults in its orientation function." (Author's abstract, IAB-Doku) ((en))FachkrÀfte, Berufsverlauf, Berufswechsel, Erwerbsunterbrechung, Ausbildungsabsolventen, junge Erwachsene, Berufskonzept, Erwerbsarbeit, adÀquate BeschÀftigung
Emotional Rollercoaster: The Inverted U-Shaped Relationship between CEO Emotions and Innovation Outcomes
While the literature suggests that CEOsâ emotions can affect organizational decision- making, leadership, and employee engagement, we know little about how they influence firmsâ culture and outcomes of innovation. Acknowledging that innovation is a critical element for long-term success, we investigate the relationship between CEO emotions and firm innovation. The results of our analysis of 1,903 firm-year observations supports our theorizing of an inverted U-shaped relationship between CEO emotions and innovation outcomes. The findings show that moderate levels of emotions lead to the highest innovation outcomes, while extremely high or low levels decrease innovation. This study contributes to the literature by applying the Yerkes-Dodson law within upper echelon theory, demonstrating a non-linear relationship between CEO emotions and innovation, and utilizing a novel algorithm to measure CEO emotions more objectively
The Third Way for the Third Sector: Using Design to Transfer Knowledge and Improve Service in a Voluntary Community Sector Organisation
This paper describes a two-year Knowledge Transfer Partnership that concluded in September 2011. Knowledge Transfer Partnerships (KTP) is a UK-wide activity that helps organisations to improve their competitiveness and productivity by making better use of knowledge, technology and skills within universities, colleges and research organisations. This paper details the outcome of a KTP between Age UK Newcastle and Northumbria Universityâs School of Design that aimed to use Design approaches to improve the charityâs services. This paper will describe the recent context for organisations operating in the Voluntary Community Sector and discuss the relevance of a Design approach to both the improvement of customer services in this circumstance, as well as the transfer of knowledge to a capacity-starved organisation. It will also document how Design was used to achieve both of these aims, and the resulting impact of this engagement on the organisation and stakeholders
ErwerbsverlÀufe von Ausbildungsabsolventinnen und -absolventen: eine Anwendung der Optimal-Matching-Technik
"Die quantitative Untersuchung von LebensverlĂ€ufen erfolgt bislang primĂ€r mit dem Verfahren der einzelne ĂbergĂ€nge fokussierenden Ereignisanalyse. In diesem Arbeitspapier dagegen wird ein Ansatz vorgestellt und diskutiert, der es erlaubt, VerlĂ€ufe 'ganzheitlich' in den Blick zu nehmen und auf explorativem Wege typische Verlaufsmuster zu identifizieren. Dieses unter der Bezeichnung 'Optimal-Matching-Technik' firmierende Verfahren zur Messung der Ăhnlichkeit bzw. UnĂ€hnlichkeit von Ereignissequenzen wird dabei nicht in Konkurrenz zur Ereignisanalyse gesehen, sondern als sinnvolle ErgĂ€nzung. Es wird hier genutzt, um die ErwerbsverlĂ€ufe einer Kohorte von Ausbildungsabsolventinnen und Absolventen zu klassifizieren und deren ZusammenhĂ€nge mit sozialstrukturellen Merkmalen einerseits sowie berufsbiographischen Orientierungsmustern andererseits zu untersuchen.
Lernen von anderen LĂ€ndern? Internationale Perspektiven zur Teilnahme an Hochschulweiterbildung
Aus international vergleichender Perspektive versucht der Beitrag, die Bedingungen zu identifizieren, die eine Teilnahme an Hochschulweiterbildung begĂŒnstigen oder erschweren, und die Frage zu beantworten, was wir von anderen LĂ€ndern lernen können. Dazu werden ausgewĂ€hlte, aufgrund sekundarstatistischer Analysen gewonnene Ergebnisse aus sieben LĂ€ndern vorgestellt und systematisch auf den lĂ€nderspezifischen institutionellen Kontext bezogen. Unsere Analyse zeigt, dass die gegenwĂ€rtige Situation und die zukĂŒnftige Entwicklung der Hochschulweiterbildung in starkem MaĂe pfad- und kontextabhĂ€ngig sind und dass aufgrund dieses systemischen Charakters die Ăbertragbarkeit einzelner Elemente eingeschrĂ€nkt ist. Dennoch bleibt Einiges von den VergleichslĂ€ndern zu lernen
Commoning by Design: Staying relational in conflict
In this presentation, we build on recent discussions of a paper presented at DRS2022 that explores the theories of the commons and their applicability to systemic design to transition existing systems from being dysfunctional to being regenerative (Schaeper, Kothari, Hamilton, 2022). As many of our social and environmental challenges have been described as a failure of design (Escobar, 2018), designers have been called to reconsider the way they work and to ultimately âredesign designâ (Akama et al., 2019; Irwin, 2015). We begin the presentation by sharing a case study of a marine protected area in South Africaâs oceans and how a commoning practice could be applied more intentionally to increase cooperation amongst system actors and apply a multispeciesâas opposed to human-centredâperspective to the management of natural, social, and immaterial resources. By drawing on our working hypothesis of how a commons approach could open up opportunities for creating the conditions of improved stakeholder cooperation, we will propose and invite further discussion around how âCommoning by Designâ could be positioned as an intentional and careful design act that aims at facilitating staying relational not only through alignment but by surfacing a plurality of voices and thereby holding space for conflicting planetary stakeholder needs, motivations and objectives
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