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Riding the Storm: Entrepreneurship, Innovation, and Strategy in Navigating Natural Disasters—A Multi-Level Study
Full text linkClimate change has led to a growing number of natural disasters. This dissertation examines how firms create, innovate, and survive in those disasters. If firms do not survive, how do we promote failed entrepreneurs to reentry into entrepreneurship? And how complex social, cognitive, and resource environments mitigate the aforementioned relationships? By integrating social capital theory, behavioral theory of the firm, and prospect theory, this dissertation constructs a framework for understanding the multifaceted relationships between natural disasters and firm/personal behaviours. In doing so, this dissertation provides actionable insights that help organizations thrive in disasters and support policymakers in fostering more resilient entrepreneurial ecosystems
Public and Faithful:The Christian Imperative in the Public Sphere in the Context of Bioethical Debates
Full text linkABSTRACT This research looks at the framing of three contemporary bioethical issues, namely: artificial contraceptives, abortion, and euthanasia and assisted suicide (EAS); and investigates the ‘reactive politicization’ of faith-based organizations (FBOs) to influence public discourse and policy on these issues. This ‘reactive politicization’ means making it a matter of law and public policy on which Christians should campaign politically. In doing so, it addresses the ethics of citizenship focusing on the place of religious reasoning in political debates in a liberal democracy. While the cases concretize the issues, these also raise a range of new dilemmas confronting religion and liberal democracies. The research draws on philosophical reflections on religion and political liberalism to explore what can legitimately be done by these FBOs to influence policy in a liberal democracy. Debates on artificial contraceptives and abortion, which deal with the question, ‘When does life begin?’ and EAS, which deal with the question ‘Is it permitted to have one’s life ended by someone else notably a physician?’ continue in the public sphere. FBOs claim these debates are particularly difficult to resolve because these are influenced by certain comprehensive beliefs and worldviews. The focus of this research is the concept of a Christian Imperative in the public sphere regarding these bioethical issues which have been reframed from a morality issue to a rights issue in the policy discourses and the response of FBOs changing their strategy from emphasizing morality to influencing state policies (amending, limiting, and eliminating legislation) on what can be called ‘beginning and end-of-life issues.’ These FBOs, however, have the obligation to respect other positions, while at the same time advocating for laws based on their beliefs in a liberal democracy. The aim is to discern how these FBOs can be faithful to their beliefs while respecting pluralism and how these FBOs can be more effective in advocating for ‘faithful’ laws in a pluralist society at the same time honoring democratic structures. While the focus is the Christian Imperative and discerning the place of religious reasoning in the public sphere, the research is concerned with a wider context regarding the ethics of citizenship (of believers, non-believers, and agnostics) in a pluralist society. It is argued that the prevailing consensus model from John Rawls (as well as revisions from Jürgen Habermas), and its constraints towards religious reasoning in debates on public bioethics, fall short in allowing Christians (and other minorities for that matter), to fully participate representing their beliefs in the political life of a genuinely pluralist state. The alternative from the Reformational tradition of religious candor in the public sphere from Nicholas Wolterstorff and Jonathan Chaplin will be explored. Following this alternative, the Christian imperative on coercive laws on bioethical issues, is faithfulness in conscientious engagement. For Chaplin, in the representative public sphere, citizens and their representatives practice confessional candor; but in the declaratory statements of the state, confessional silence should be practiced. This research further explores how this conscientious engagement can be done by FBOs through Catholic Voices’ strategy of understanding the value that is shared and the limitations and prejudices ---the frames---and reframing to create a culture of encounter. Lastly, the research proposes Carter Snead’s anthropological notion of “embodiment,” a potentially accessible evaluative standard, with enough interpretive flexibility that the state can mobilize as the core of a more impartial bioethics legislation
Resilience in care: An integrative negotiation perspective on the behavioral dynamics of resource exchanges in responding to setbacks
No full textIssue Caring is inextricably intertwined with resilience: the ability of individuals and collectives to deal with setbacks. To respond resiliently, actors draw on resources that may lie beyond their direct reach, requiring the engagement of others within the care system. The complex, hierarchical, and fragmented nature of care systems both necessitates and complicates cooperation and coordination between actors as they pursue or support resilient responses.Critical Theoretical Analysis Relational perspectives on resilience provide a starting point for understanding the relational processes determining whether and how resources are exchanged. However, they do not provide insight into the behavioral dynamics that help explain how interdependent actors negotiate their relationships as they pursue or support resilience.Advance Drawing on the integrative negotiation theory, we extend resource-based and relational perspectives on resilience by elucidating the interactional specifics of how actors can collaborate to effectively deal with setbacks—even when they pursue seemingly conflicting outcomes. Highlighting the importance of voice, epistemic motivation, and prosocial motivation, we capture the interpersonal dynamics that shape (a) awareness of resource needs and others’ ability to provide these; (b) interactions informing decisions on whether and how resources are exchanged; and (c) the ability to find integrative solutions that go beyond zero-sum exchanges, serving all actors’ interests and needs.Practice Implications Our framework informs the collective development of resilient solutions. We highlight the behavioral repertoires (i.e., the interactions through which resources are pursued, negotiated, and/or shared), enabling actors within care systems to build on their interdependencies as they pursue or support resilient responses to setbacks
Computational Analysis of the KnowBe4 Identity Fraud Case by a Multi-adaptive Dynamical System Model
No full textThis research analyses how early detection and mitigation responses can reduce the impact of a deepfake-based cyber-attack, using the real-world case of KnowBe4 as inspiration. In that case, an attacker used deepfake technology to impersonate a legitimate job applicant and infiltrate the company. Based on this scenario, we developed a dynamical system model to test various combinations of detection thresholds and mitigation speeds, focusing on two primary outcomes: data access and ransom threat. We ran 25 simulation scenarios to explore how these variables affect system behaviour over time. The results showed that when detection was weak, even with fast mitigation, both outcomes increased significantly. In contrast, when detection was strong, the system stayed more stable, and threats were less likely to escalate. Our What-If analysis confirmed that the most severe outcomes occurred under low detection conditions, showing that early detection acts as the first and most effective barrier against deepfake-based attacks, while mitigation is more effective when used as a supporting response rather than a standalone solution. Based on these findings, we recommend that organizations prioritize investments in advanced detection tools, especially those capable of identifying deepfake content or synthetic identities early in the process.</p
From vocational education to the labour-market. The impact of schoolbased or work-based practical training
No full textFrom vocational education to the labour-market: the impact of schoolbased or work-based practical training In vocational education (mbo), job-specific skills are (partly) taught in practice at a training company, known as vocational practical training (Beroepspraktijkvorming, BPV). The mbo system offers two learning pathways, which differ in terms of the scope of BPV. In the work-based learning pathway (bbl), the scope of BPV is much larger than in the school-based learning pathway (bol). Mbo graduates who have been trained via bbl are also more likely to stay at the training company after completing their studies. This article examines to what extent a successful transition from education to the labor market is related to BPV through bol or bbl and the opportunity to work at the training company after graduation. The study focuses on mbo graduates from the 2014/2015 academic year. Information is available on their labor market position one year and five years after graduation. We find that bbl graduates are in a better labor market position shortly after graduation than bol graduates. Five years after graduation, their position is still better, but the gap has decreased. We found no evidence that the better position of bbl graduates is due to them receiving more offers from their training companies to stay on after graduation. However, the relationship between an offer from the training company and early career outcomes differs between graduates of bbl and bol. For bbl graduates, an offer from the training company, especially if accepted, is associated with a better short-term labor market position. For bol graduates, an offer is associated with a better labor market position in the longer term.</p
Addressing Gender in Authenticity and Inclusion at Work:Nuancing Conservation of Resources Theory With Social Role Theory
No full textIn this paper we elucidate how gender may influence the mechanisms and conditions under which perceived inclusion climate facilitates authenticity at work. We nuance conservation of resources theory with social role theory to argue that perceived inclusion climate acts as a caravan passageway through which authenticity at work can be fostered, yet how inclusion climate relates to authenticity is different for men versus for women. We hypothesize that men will feel more authentic when they perceive their organization to be inclusive because such perceptions enable them to feel unique, whereas women will feel more authentic when in inclusive organizations because such environments foster their belongingness. In a time-lagged study, we find that for women, it is belongingness that is the mediating process, whereas for men, it is both uniqueness and belongingness. We additionally propose, and find, that structural empowerment, as an HRM contextual resource caravan, moderates the relationships between perceived inclusion climate and belongingness/uniqueness for women but not for men. Here, structural empowerment is particularly important for women's needs for belongingness and uniqueness when they perceive their organization be not very inclusive. Overall, we contribute to workplace inclusion and authenticity literatures by underscoring the need to consider gender differences in more depth.</p
Divergent paths: Unraveling heterogeneity in Alzheimer's disease and Lewy body disease
Full text linkThe papers presented in this thesis aimed to advance our understanding of biological heterogeneity in several age-related dementias, with a particular focus on Alzheimer’s disease (AD) and Lewy body disease (LBD), and to characterize the clinical phenotypes associated with these variations. First, we aimed to gain insights into the clinical relevance of an imbalance between different amyloid-β (Aβ) species. Second, we investigated the existence of multiple distinct spreading patterns in Lewy body pathology (LBP) across different etiologies, using data-driven machine learning modeling. Third, we assessed the effect of Lewy body (LB) co-pathology on atrophy and clinical progression in AD. Fourth, we aimed to develop a multidimensional, biomarker-based framework that categorizes memory clinic patients based on the presence, extent, and sequence of several common pathologies. Fifth, we set out to develop and evaluate a cerebrospinal fluid (CSF)-based biomarker of LBP. The key findings of this thesis include: 1. An imbalance towards more soluble relative to aggregated Aβ species is associated with AD genetic risk, elevated levels of AD-related CSF biomarkers, and worse cognitive outcomes. 2. Multiple different progression patterns of LBP exist, each associated with distinct clinical and pathological characteristics. 3. LB co-pathology is associated with greater posterior cortical hypometabolism and exacerbated cognitive decline in AD. 4. Categorizing individuals based on the presence, extent, and order of (co-)pathologies provides meaningful information on individual variation in disease trajectories. 5. A two-step approach that combines smell-function testing with confirmatory CSF α-synuclein testing can accurately predict the presence of brain LBP while reducing the number of required lumbar punctures. 6. Endpoint dilution CSF RT-QuIC can be used to estimate the amount of α-synuclein pathology and shows correlations with brain LBP and clinical severity
Evolving Penile Cancer Care:Advancement of Treatment Outcomes and Patient Well-being
No full textThis thesis focuses on optimizing outcomes for patients with penile cancer, aiming to improve both survival and (sexual) quality of life. The work consists of two main parts: the first addressing oncological outcomes and innovations in treatment, and the second focusing on patient well-being and functional recovery.Chapter 2 evaluates the development of penile cancer care in the Netherlands over the past 30 years, including more than 3,100 patients. Although penile cancer remains rare, its age-standardized incidence has increased. The findings confirm a strong trend toward centralization, with growing numbers of referrals to expertise centers. Patients treated in these centers demonstrated significantly better survival compared with those treated in regional hospitals, emphasizing the value of specialized care for rare malignancies.Chapters 3 to 5 focus on the sentinel node procedure. After more than a decade of clinical use, nanocolloid—a human serum albumin-based tracer—was replaced by Nanoscan due to production discontinuation. Chapter 3 demonstrates that despite minor chemical differences in ICG-binding between ICG 99mTc nanocolloid and ICG 99mTc nanoscan, no significant differences were found in sentinel node visualization or complication rates. Nanoscan is therefore a safe and effective replacement.In Chapter 4, a systematic review of hybrid fluorescent and radioactive albumin-based tracers was conducted, summarizing 60 clinical studies encompassing over 2,000 patients across 14 tumor types, including penile cancer. These results confirm the clinical value and safety of hybrid tracer technology for sentinel node mapping.Chapter 6 explores skip metastases (SKM), defined as metastatic lesions in the corpora cavernosa or spongiosum without direct extension from the primary tumor. SKM presence was an independent predictor of poorer cancer-specific survival. Interestingly, a proportion of SKM-positive patients showed atypical metastatic patterns, such as distant metastases without lymph node involvement. Patients with SKM and pN0 disease had survival outcomes comparable to those with advanced nodal or distant metastases, indicating the aggressive nature of SKM.The second part focuses on quality of life and sexual well-being. Chapter 7 shows that penis-sparing surgery effectively preserves organ function and overall life quality but increases the risk of local recurrence due to narrow surgical margins (>1 mm). The long-term survival impact of these recurrences remains unclear, and data on sexual outcomes are limited.In Chapter 8, sexual satisfaction following surgery is analyzed. Men who underwent penis-sparing procedures reported greater sexual activity and higher satisfaction than those who underwent partial or total penectomy. These findings highlight the importance of integrating functional and psychosocial aspects into treatment planning.Chapter 9 addresses the follow-up of node-negative penile cancer patients. Late lymph node metastases were rare and usually developed within the first year after treatment. Based on these findings, a new follow-up protocol is proposed: intensive surveillance with routine groin ultrasonography during the first year, followed by less frequent examinations thereafter. The frequent occurrence of local recurrences underlines the importance of patient self-examination, which could safely reduce follow-up visits by up to 50% compared to current practice.In conclusion, this thesis demonstrates that centralization of penile cancer care and the application of innovative diagnostic, surgical, and surveillance approaches significantly improve survival and quality of life. Future care should emphasize personalized, multidisciplinary management in which oncological outcomes and patient well-being are equally prioritized.<br/
Optimizing physical recovery after oncological surgery:A blended physical activity and nutrition intervention
No full textMajor oncological surgery is frequently associated with substantial functional decline. To limit muscle mass loss and associated decline in physical functioning, it is crucial for patients to increase their physical activity levels and meet protein intake requirements following oncological surgery. However, post-discharge supportive care interventions focusing on functional recovery are limited. Digital health tools— such as smartphone apps and activity trackers— in combination with coaching by allied healthcare professionals may offer a promising solutions by providing accessible support and continuity of care in patients’ own environments. The aim of this thesis was to develop and evaluate a blended intervention designed to provide optimal physical recovery after hospitalization in patients who have undergone gastrointestinal or lung cancer surgery. Chapter 2 evaluates if self-monitoring of physical activity using an activity tracker and smartphone app after hospital discharge is feasible in patients after gastrointestinal or lung cancer surgery. Chapter 3 contains a systematic review and meta-analysis, evaluating the effectiveness of physical activity interventions using activity trackers during or after inpatient care. Based on the results of chapter 2 and 3, the Optimal Physical Recovery After Hospitalization (OPRAH) intervention was developed. The OPRAH intervention combines self-monitoring of physical activity and protein intake, with remote coaching by a physiotherapist and dietician after hospital discharge. Chapter 4 evaluates the feasibility of the OPRAH intervention and the associated study procedures as a prelude to performing a randomized controlled trial. In chapter 5 the protocol for the multicenter randomized controlled trial (RCT) to investigate the effectiveness of the OPRAH intervention compared to usual care is described and results of the multicenter RCT are presented in chapter 6. Chapter 7 presents qualitative data on patient’s experiences with the OPRAH intervention. Furthermore, chapter 8 evaluates the extent to which the OPRAH intervention is conducted as initially designed, by assessing the implementation fidelity. The findings of this thesis indicate that the OPRAH intervention can effectively enhance functional recovery following gastrointestinal and lung cancer surgery. However, further research is needed to determine the optimal patient selection criteria and coaching intensity to maximize patient benefit while ensuring cost-effectiveness. Moreover, targeted adaptations and greater personalization are crucial to address health inequities and improve accessibility for hard-to-reach populations
Where the Really Hard Problems Went
No full textMany if not all NP problems show a solvability phase transition along a secondary parameter for any fixed input size. These secondary parameters and associated solvability phase transitions have been identified and in many cases, the solving algorithms used for these problems require significantly more time for instances close to this phase transition.This hardness-near-the-phase-transition-phenomenon has profound implications for the NP-completeness of the problems themselves. Being a member of the class \emph{NP} implies that a problem has no exact algorithm of subexponential runtime for the worst case instances for increasing input size. But these worst case instances are rather scarce, and appear to reside around the solvability phase transition. For this reason, further study of this phenomenon is warranted. In this dissertation, we will four different problems in NP: the Hamiltonian cycle problem, the asymmetric traveling salesman problem, the partition problem and the perfect rectangle problem. For the Hamiltonian cycle problem, we show that very rare but super hard instances exist very far from the solvability phase transition. These instances display a degree of universal hardness, requiring vast amounts of runtime for all major published exact backtracking algorithms. But we also replicate earlier results for this problem, showing that in randomly generated ensembles, the hardest instances are all located near the solvability phase transition. We conjecture, by an argument from Kolmogorov complexity, that these super hard instances, which are highly structured, are very unlikely to show up in randomized ensembles, solving the paradox. These results could encourage the community to explore the influence of an instance structure on hardness.For the asymmetric traveling salesman problem, we also replicated earlier results, claiming the standard deviation of the random instance generation function for the values in the cost matrix could be used as a secondary parameter for the problem's instance hardness. These results however, turned out to be flawed. The culprit is an interplay between the lognormal generation function and an ensuing integer roundoff for the matrix values. We show that the hardness difference for the instances almost completely disappears when the roundoff is omitted, but we also show that when the roundoff is preserved, the resulting number of zeroes in the matrix is directly related to the aforementioned standard deviation. For the partition problem, a secondary parameter can be found in the number of bits per integer in the set. If this ratio is low, the instance typically has many perfect solutions, and one is easily found. If this ratio is high, the entire search tree must be traversed to find the optimal split. In our contribution, we show that the problem's algorithmic hardness does not only depend on the absolute magnitude of bits per integer, but also on their actual distribution. The results however do invoke other questions on the hardness of this problem in NP, namely whether a deliberate search for distributions instead of instances can identify hard regions, but also whether easy and hard instances can be separated, as the solution distribution in the instance space might be fractally structured.For the perfect rectangle packing problem, we identified a secondary parameter in the parameter `randMax', which determines the maximum side length of the rectangles in an instance. The midpoint of this phase transition lies very close to O(n sqrt(n)), which is very different from other phase transition midpoints. It begs further investigation, but the problem is much harder than the other NP-complete problems in this thesis, and demands significantly more time and space