Magneto-capillary valve for integrated biological sample preparation

A major technological trend in in-vitro diagnostics is the integration and miniaturization of laboratory procedures into so-called ‘lab-on-chip’ devices. The aim is to achieve better integration of diagnostics into the medical workflow by providing compact devices that can analyze patient samples at the point of care, close to the patient. Ease-of-use is an important characteristic of point-of-care diagnostics. One specific feature that enables such easy-to-use devices is a ‘sample in – result out’ type of performance. However, in many cases a raw body fluid is not directly suitable for analysis. Therefore, an elaborate multi-step process of sample preparation is required before actual analysis of the sample can take place. While many detection technologies have been fully automated and successfully miniaturized and integrated into a lab-on-chip format, sample preparation has been staying behind on this trend. As a result, sample preparation requires a substantial amount of manual handling by a trained operator and is often the bottleneck in the process from sample to result. Integration and miniaturization of automated sample preparation is thus required to provide the ease-of-use and portability that is needed to bring diagnostics closer to the patient. This thesis aims at advancing the level of integration and miniaturization of automated biological sample preparation to enable point-of-care applications with a ‘sample in – result out’ type of performance. For this purpose, a novel microfluidic actuation concept is proposed: the magneto-capillary valve (MCV). The MCV technology is based on stationary microfluidics, in which discrete units of liquid are present at fixed positions in a microfluidic device. The MCV cartridge is a capillary device, in which aqueous liquids are confined by capillary forces resulting from specific features of the cartridge. Magnetic particles are transported through a hydrophobic valve medium from one stationary liquid to another by externally applied magnetic forces. The MCV technology provides a means for solid phase extraction, which is a common type of sample preparation. Analytes are coupled to magnetic particles in the sample matrix and are transported through one or more washing buffers to be finally eluted from the particles in a buffer that is appropriate for detection of the analyte. A key advantage of the MCV is its high valving efficiency due to the minimal quantity of liquid that is co-transported with the particles carrying the analyte. Moreover, by choosing a large sample volume and a small elution volume, the sample can be enriched and its volume matches the sample volume requirements for lab-on-chip devices. The envisioned system consists of a low-cost disposable cartridge that is driven by an instrument containing a magnetic actuation system like, for example, a movable permanent magnet. Many cartridges of different designs and various architectures were fabricated with a lead time of less than a week, due to a well-defined and yet very flexible fabrication process. In total, almost 1000 cartridges were fabricated over a period of about 2 years. This large number of cartridges was necessary to investigate the principles of magneto-capillary valving, to create options and define limitations of the MCV concept, and to test the performance of the MCV concept in biological sample preparation. Several MCV instruments were built as experimental setup to investigate the behavior of the valve and as instrument to enable experiments of biological sample preparation. The setup allows for quantification of the magnetic force that is applied to the particles. This quantification is realized by combining recorded images of the magnetic particle cloud with the measured susceptibility of the particles and the calculated magnetic field of the magnet. The behavior of the valve is described by a model that balances magnetic forces, capillary forces and friction forces. The performance of the MCV was evaluated by investigating the physics of magneto-capillary valving. The valving efficiency, the transport of magnetic particles, and pinch-off were investigated experimentally to characterize the valve operation. The conditions for successful operation of the valve were defined as a function of several design parameters. Investigation of the friction forces resulted in understanding of the intra-chamber dynamics, leading to the concept of force gradient mixing. Experimental results of DNA purification from spiked water and plasma samples demonstrate the feasibility of integrated biological sample preparation using the MCV technology. The performance of DNA purification in MCV cartridges was comparable to the performance of common commercially available solutions, while the MCV cartridge technology is much less complex. Integrated enrichment of DNA from 800 µl water samples showed an effective enrichment of 40 times, thus providing a substantial increase in detection sensitivity. DNA was also extracted successfully from samples with THP1 cells, which is a step further towards the total integration of a molecular test. The enrichment of proteins that was demonstrated in the MCV technology enables a whole new range of applications based on immunocapture of biomolecules. The approach of stationary microfluidics provides a strong reduction in complexity of the system, which is particularly valuable for point-of-care devices. From evaluation of the various valve architectures, the geometrical air valve appears to be the most suitable magneto-capillary valve architecture for integrated biological sample preparation. It features at the same time the best performance for a wide range of biochemical assays, as well as simplicity, which is essential for integration and for the concept of low-cost disposable cartridges. With that, the MCV technology has the potential to open new opportunities for integration and miniaturization of automated biological sample preparation

Working parents’ use of work-life policies

Neste artigo, examinamos a utilização das políticas de conciliação entre a vida profissional e a vida privada pelos pais trabalhadores, em três organizações do sector financeiro dos Países Baixos. Analisamos os obstáculos e os apoios a uma utilização efectiva destas políticas pelos pais trabalhadores e a medida em que ela influencia, por sua vez, o equilíbrio por estes sentido entre a sua vida profissional e familiar. Recolhemos dados de inquérito em três organizações do sector financeiro holandês: numa organização do sector público e em duas empresas privadas. As três diferem consideravelmente quanto à cultura organizativa e às práticas laborais. Duas das organizações são caracterizadas por uma cultura contrária à conciliação entre a vida profissional e a vida privada e a outra por uma cultura que lhe é favorável. Os resultados indicam que as características do agregado familiar e a cultura da organização nesta matéria determinam a utilização das políticas de conciliação entre a vida profissional e a vida privada. No que respeita ao equilíbrio entre a vida profissional e a vida familiar dos pais trabalhadores, a cultura da organização é uma determinante fundamental, não se encontrando qualquer impacto da utilização das políticas.In this paper, we examine working parent’s use of work-life policies in three financial sector organizations in the Netherlands. We analyse the barriers and support regarding the actual take up of work-life policies by working parents and to what extent this in turn influence their experienced work-life balance. We collected survey data in three Dutch financial sector organizations: one public sector organization and two private firms. All three differ considerably regarding their organizational culture and working practices. Two of the organizations are characterised by a contradictory work-life culture, and one by an approving work-life culture. Findings point out that household characteristics and the work-life culture in the organization determine the take up of work-life policies. With respect to the work-life balance of working parents, organizational culture is an important determinant, no impact is found of the utilization of policies.Cet article analyse l’utilisation des politiques de conciliation entre vie professionnelle et vie privée par les parents qui travaillent, au sein de trois organisation du secteur financier des Pays-Bas. Il analyse les obstacles et les aides à une utilisation effective de ces aides par les parents qui travaillent et dans quelle mesure elle influence, à son tour, l’équilibre qu’ils ressentent entre leur vie professionnelle et leur vie familiale. Les données de l’enquête ont été recueillies au sein de trois organisations du secteur financier hollandais: une organisation du secteur public et deux du secteur privé. Leur différence est considérable quant à la culture organisationnelle et aux pratiques de travail. Deux des organisations sont caractérisées par une culture contraire à la conciliation entre vie professionnelle et vie privée et l’autre par une culture qui lui est favorable. Les résultats indiquent que les caractéristiques du ménage et la culture de l’organisation concernant cette question déterminent l’utilisation des politiques de conciliation entre vie professionnelle et vie privée. Quant à l’équilibre entre vie professionnelle et vie familiale des parents qui travaillent, la culture de l’organisation est un facteur essentiel, aucun impact de l’utilisation des politiques n’étant observé.En este artículo examinamos las políticas de conciliación entre la vida profesional y la vida privada de los padres trabajadores, en tres organizaciones del sector financiero de los Países Bajos Analizamos los obstáculos y apoyos en la utilización de estas políticas por padres trabajadores y a su vez, en que medida ellas influyen en el equilibrio entre vida profesional y familiar. Recogimos datos de encuestas en tres organizaciones del sector financiero holandés: una organización del sector público y dos empresas privadas. Las tres difieren en forma considerable en relación a la cultura organizativa y a las prácticas laborales. Dos de las organizaciones se caracterizan por una cultura contraria a la conciliación entre la vida profesional y la privada y otra por una cultura que le es favorable. Los resultados indican que la características del agregado familiar y la cultura de organización en esta materia determinan la utilización de las políticas de conciliación entre la vida profesional y la vida privada. En lo que respecta al equilibrio entre la vida profesional y familiar de padres trabajadores, la cultura de organización es un factor fundamental, si no se encuentra algún impacto en la utilización de dichas políticas

The effects of work alienation on organizational commitment, work effort and work-to-family enrichment

Aim: The aim of this study was to analyze the effects of work alienation on organizational commitment, work effort and work-to-family enrichment. Background: There is substantial research on the effects of work alienation on passive job performance, such as organizational commitment. However, studies analyzing work alienation on active performance, such as work effort, and outside work, such as work-to-family enrichment, are scarce. Method: Two dimensions of work alienation are considered: powerlessness and meaninglessness. Hypotheses are tested using surveys collected among a national sample of midwives in the Netherlands (respondents: 790, response rate 61%). Results: Findings indicate that work alienation (powerlessness and meaninglessness) influence organizational commitment, work effort and – to a lesser extent - work-to-family enrichment. High work meaninglessness, in particular, has negative effects on these outcomes. Conclusion: When people feel that they have no influence in their work (hence, when they feel ‘powerless’) and especially when the feel that their work is not worthwhile (when they feel ‘meaningless’), this has substantial negative effects. Implications for nursing management: Managers should increase the meaningfulness people attach to their work, thereby maintaining a high-quality workforce. Possible strategies include: 1.Improving person-job fit, 2. Developing high-quality relationships, 3. Better communicating the results people help deliver

Community, work and family in diverse contexts and changing times

The 8th International Community, Work and Family conference took place in Malta at the Valletta campus of the University of Malta between the 23rd to the 25th May 2019. In a pre-COVID-19 world with no traveling restrictions, the conference brought together over 100 experts, academics, and students from a broad range of countries and disciplines to focus on the theme of Community, Work and Family in Diverse Contexts and Changing Times. The research presented during the conference highlights some of the challenges that communities, organizations and families are facing in the twenty-first century across diverse and rapidly changing contexts. The topics presented spanned from broad studies that analyze the work-life interface of well-studied groups such as fathers and mothers, to other clusters that are generally less well-researched such as the police and the military, migrants, solo entrepreneurs, the LGBTIQ community, and those who work with people with special needs. The recurrent theme of the gendered division of labor and work-life measures was discussed by various researchers, as were the issues of flexible work, family policy, and the impact of technology. It was refreshing to note that various researchers focused on the issue of community as a source of support, whilst others explored how peer, supervisor and management support impacts work-life issues. Overall, the conference provided a diverse and rich range of scholarly material upon which to develop this special issue for Community, Work & Family. [...

Parents' experiences of flexible work arrangements in changing European workplaces

Various leaves and other forms of flexible working arrangements have been implemented in workplaces to support employees with family commitments. Some are a response to public policy, others developed voluntarily. However, research examining the effectiveness of these policies in a search for “good practices” often neglects the impact of specific national and workplace contexts. Some researchers are calling for more attention to social systems, especially at the macro and meso levels, and the relationships between them, to extend understanding of work family processes and experiences. We argue that this is critical for evaluating work-family policies and practices. However it is important to recognize that social systems are not static. They are dynamic and changing, particularly in the context of globalization processes. Drawing on data from six case studies of private sector organizations undergoing rapid change and transformation, carried out in six European states, as part of a qualitative cross-national EU project (Transitions)1 , this paper explores the impact of multiple layers of context on parents’ experiences of flexible working arrangements for managing work and family boundaries. The study shows that although various aspects of macro layers of context are important and it is easier to make use of flexibility to combine work and parenting in some national and workplace contexts than others, changes taking place at the workplace level in response to global competition and efficiency drives can undermine both regulatory and voluntary initiatives to enhance flexibility for parents. This is occurring across national boundaries. Some implications for debates on “good practices” and for future work-family research are discussed

Managing work-life policies in the European Workplace: explorations for future research

In this paper we focus on the implementation and management of work-life policies in the workplace and the key role of managers in this context. We review the existing literature, enabling us to set a research agenda focused on explaining managerial attitudes and behaviour toward work-life policies in different organisational and national contexts. The evidence found in several studies suggests that managers often receive mixed messages about the implementation of work/life policies because these policies are not embedded in the workplace; managers are often unaware of such policies and lack training in them, leading to inconsistency in implementation and short-term thinking rather than a long-term perspective that cherishes human capital. Our review points to the need for more research allowing a full understanding of managerial attitudes and behaviour in different organisational and national contexts. Although a few interesting studies do exist, research in the field is still in its infancy. More research is needed, in particular systematic studies with well-developed theoretical frameworks. Keywords Line managers, work-life policies, allowance decisions, European workplac