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Rethinking Purchasing and Supply Management Education for Sustainability and Innovation Challenges:Crafting a Future-Ready Competency-based Curriculum Design
Get PDFThe strategic responsibilities of purchasing and supply management (PSM) professionals increase since they need to contribute to creating innovative solutions for environmentally sustainable products and services. Addressing this, our study introduces a competency-based curriculum design that surpasses traditional PSM knowledge dissemination, equipping students with vital interpersonal skills, intrapersonal attitudes, and professional competencies for sustainability and innovation. In collaboration with educators, PSM professionals, and students, we developed a future-ready course structure, including a massive open online course (MOOC) designed to meet evolving workplace demands. This curriculum offers practical, accessible tools for PSM educators to enhance their courses through a student-centred, project-based methodology. Our research presents an innovative educational framework, preparing students to excel in leadership roles that drive sustainability and innovation within global supply chains. By equipping students with these essential competencies, higher education institutions can develop the next generation of PSM leaders capable of fostering meaningful change in their industries
Malaria survey data and geospatial suitability mapping for understanding spatial and temporal variations of risk across Kenya
Get PDFMalaria remains a public health concern in Kenya where children and pregnant women are vulnerable groups. The common interventions in place to fight malaria include using insecticide-treated bed nets (ITNs), knowledge and awareness about malaria, and intake of malaria anti-malaria drugs. Despite the availability of these interventions, Kenya still records more than 10,000 clinical cases annually. In this study, we examined how malaria and interventions varied across Kenya for 2015 and 2020. We analyzed the Kenya Malaria Indicator Survey (N = 10,072) for 2015 and, (N = 11,549) for 2020, and climate data with Fuzzy overlay method to examine how malaria and its interventions relate to environmental conditions required for malaria. The study found that 79 % of malaria cases were distributed in lake endemic, 11 % in coastal endemic, 7 % in highland epidemic, and 3 % in seasonal zone. Use of Insecticide-treated bed nets (ITNs) was 77 % in lake endemic, 13 % in coastal endemic, 9 % in highland epidemic, and 1 % in seasonal zone. Knowledge about malaria was 82 % in lake endemic, 9 % in highland epidemic, 6 % in coastal endemic, and 3 % in seasonal zone. Additionally, based on climate data, lake endemic zone was 94 % suitable for malaria transmission compared to other zones. Despite the use of ITNs and awareness about malaria, malaria transmission continues to be a threat especially in counties in the lake endemic zone. Furthermore, place of residence, climate factors, ownership of ITNs may be associated with malaria in the region
Do your students engage with socioscientific issues?:Socioscientific capital in civic science education
Get PDFThis dissertation aims to strengthen socioscientific issues (SSI) education by focusing on the resources available to students. SSI education is a type of science and citizenship education that supports students’ informed and critical engagement with social issues that have scientific or technological dimensions. This dissertation explores students’ SSI-related resources relevant to their engagement with SSI, such as their attitudes and social resources. SSI education and students’ resources are two separate fields of research that are rarely bridged. In addition, a comprehensive overview of the resources that students bring to learning and decision-making about SSI has not been previously provided. Lida Klaver combines literature on SSI education with studies on students’ resources to introduce the concept of socioscientific capital, emphasizing the importance of considering students’ resources in SSI-based teaching. To enable researchers to study and account for students’ SSI-related resources, and to help teachers to get to know their students’ resources, this dissertation includes the development and validation of two questionnaires: the Pupils’ Attitudes towards Socioscientific Issues (PASSI) questionnaire and the Use of Sources of Knowledge (USK) questionnaire. These questionnaires were used to get insight into student differences regarding engagement with SSI, resulting in differing patterns of students’ USK that were shown to be related to their attitudes. The final study builds upon the arguments and findings of the first three studies. This study is an exploration of the effects of SSI-based teaching on students’ attitudes toward SSI, considering socioscientific capital (as indicated by students’ USK profile). The overall discussion of this dissertation focuses on the feasibility of SSI-based teaching and a socioscientific capital approach in the Netherlands. This discussion provides valuable points of departure for the implementation of a socioscientific capital approach in primary and secondary education, keeping in mind the challenges and opportunities that teachers face
Double-Extortion Ransomware:A Study of Cybercriminal Profit, Effort, and Risk
Get PDFIn the rapidly evolving world of cybercrime, law enforcement agencies are increasingly challenged to adapt their strategies and tools to effectively combat digital threats. This Ph.D. dissertation investigates the criminal decision-making processes behind ransomware attacks, including the human factors, economic incentives, and risks involved. The dissertation combines empirical analysis of ransomware incidents, the effectiveness of police interventions, and behavioral insights from offenders to offer a deeper understanding of how interventions can influence ransomware attacks.A key finding of the research is the importance of understanding offenders' economic calculations, including profits, effort, and risk, which are central to Rational Choice Theory. Additionally, the study explores the role of law enforcement interventions, such as sanctions, arrest strategies, and the use of decryptors, in disrupting ransomware activities. By applying data-driven models, including capture-recapture methodology and hurdle model estimation, the dissertation provides a comprehensive approach to estimating the prevalence of ransomware attacks and understanding the effectiveness of law enforcement measures. This research aims to improve the capacity of law enforcement to design more effective, evidence-based strategies to combat ransomware, ultimately contributing to a safer digital environment
Effects of hyperglycemia on neuronal network function in an in vitro model of the ischemic penumbra
Get PDFIntroduction: Hyperglycemia is common in acute ischemic stroke, and associated with unfavorable outcome. However, the optimal glucose level is not known and cellular effects of hyperglycemia under hypoxia are largely unclear. We assessed how the extracellular glucose concentration affects cultured neuronal networks under experimental in vitro conditions, to provide a starting point for assessment of mechanisms at the neuronal network and cellular levels. Methods: We used in vitro cultured rat neuronal networks on micro-electrode arrays (MEAs) and glass coverslips. Twenty-four hours of controlled hypoxia was induced. We measured neuronal network activity during baseline (normoxia, 6 h), 24 h of hypoxia, and 6 h after reoxygenation, defined as the summed number of action potentials in 1 h bins. Apoptosis was determined intermittently with caspase 3/7 staining and microscopy. We compared groups of networks under glucose concentrations of 5.0 mmol/L, 7.0 mmol/L, 9.0 mmol/L, and 12.0 mmol/L. Results: Overall, during hypoxia, a gradual decrease in neuronal network activity and increase in apoptosis was found. There were faster decrease in activity (p < 0.01) and more apoptosis after 24 h of hypoxia under glucose levels of 12 mmol/L in a single-well MEA set-up (p < 0.05), and more apoptosis in glass coverslips with glucose levels of 12.0 mmol/L in comparison with 5 mmol/L (p = 0.03). These differences were not observed in multi-well MEAs, in which effects of hypoxia were much smaller than in single-well MEAs. Conclusion: Hyperglycemia was associated with a more rapid decrease of neuronal network activity during and more apoptosis after 24 h of hypoxia in cultured neuronal networks. Loss of neuronal activity and apoptosis probably play a role in poorer outcomes of stroke patients under hyperglycemia. Our model provides a starting point for further assessment of pathomechanisms.</p
Towards a gas independent thermal flow meter
Get PDFFlow sensors have been used in diverse applications ranging from medical equipment and environmental monitoring to industrial automation and energy production. They play a crucial role in precisely measuring fluid flow rates, with various techniques such as thermal, differential-pressure, cantilever-based, ultrasonic, and Coriolis mass flow sensors. Among these, thermal flow sensors stand out for their fast response time, low cost, simple fabrication, and straightforward measuring principle.The working principle of thermal flow sensors is based on heat transfer through conduction and convection from a heated element to the surroundings. The simplest way to make a thermal flow sensor is using an electrically heated wire in which, when a fluid flows over the heated element, the temperature drops off so that the resistance of the wire changes as a function of the fluid’s velocity.Different typologies for thermal flow sensors, such as anemometry, calorimetry, and times-of-flight, and sensing transduction principles, like thermoresistive, thermoelectric, thermoelectronic, and frequency analog, can be used to achieve the desired results. Despite their advantages, thermal flow meters depend on fluid properties like thermal conductivity and volumetric heat capacity, requiring calibration for different fluids. Therefore, having medium-independent thermal flow sensors is becoming a very attractive solution. To address this, researchers have proposed methods such as utilizing different measurement principles and excitation techniques, including DC and AC excitations, multi-parameter sensors, and velocity-independent sensor designs to extract fluid properties.This research aims to develop a micromachined medium-independent thermal flow sensor capable of accurately measuring flow rates independent of fluid composition using different excitation techniques and a velocity-independent fluid property sensor design
Disclosing Evidence in Investigative Interviews: What Can the Research Tell Us and What Does it Mean for Training?
Get PDFResearch shows that attempting to pressure and overwhelm interviewees to align with evidence by, for example, disclosing too much evidence at the earlier stages of an interview often results in unreliable statements and can facilitate opportunities for deceptive interviewees to deceive convincingly.By encouraging interviewees to address the available evidence before disclosing it (late timing of disclosure) or drip-feeding the evidence throughout an interview (gradual method of disclosure), it becomes easier to elicit and explore statements that contradict available evidence; and these disclosure methods may encourage interviewees to reveal information that facilitate more accurate credibility assessments.Due to the uncertainty and unpredictability of operational interviews compared to laboratory studies, training on evidence disclosure should focus on appropriate adaptive use rather than pure implementation of theoretical frameworks and protocols
Spatial analysis of multiple ecosystem service flows from natural and cultural landscapes in the Ethiopian highlands
Get PDFEcosystem services (ES), the benefits of natural ecosystems, are essential for human well-being. Remnant ecosystems, including forests, wetlands, and culturally significant landscapes, play a pivotal role in food security and biodiversity conservation. Despite their global recognition, the integration of ES into Ethiopian environmental and agricultural policies remains limited. This dissertation examines the contributions of remnant ecosystems to ES, the impacts of ecosystem fragmentation, and the inclusion of ES in Ethiopian policies, offering guidance for conservation and sustainable development in the degraded Ethiopian highlands.The first study (Ch. 2) highlights the importance of sacred church forests in supporting wild pollinators critical for crop pollination. By examining crop flower visitation within a 1,500 m buffer, the study found that visitation declines with distance, while forest size, age, proximity, and functional richness enhance pollination. These findings stress the significance of conserving sacred forests for biodiversity, cultural values, and food security, advocating for their integration into conservation policies.The second study (Ch. 3) investigates the spatial flow of ES, such as grass biomass, microclimate regulation, crop pollination, and soil erosion retention, from remnant ecosystems. Results show that ES flow diminishes with distance, with higher concentrations near forests and wetlands. Ecosystem fragmentation significantly reduced ES flow, underscoring the importance of preserving fragmented ecosystems to sustain ES and inform conservation strategies. The third study (Ch. 4) examines the long-term effects of ecosystem fragmentation on ES delivery. The study links patterns like ecosystem area, perimeter-area ratio, and patch proximity to declines in ES over two decades, offering valuable insights for landscape planning and conservation.The final study (Ch. 5) evaluates ES integration into 25 Ethiopian policies. While ES are acknowledged, their incorporation is inconsistent, with agricultural policies prioritizing provisioning services and environmental policies focusing on regulating and cultural services. The study calls for a comprehensive approach to balance ecosystem conservation and competing land uses. In summary, this thesis underscores the need to preserve remnant ecosystems and integrate ES into Ethiopian policies to achieve sustainable development in fragmented landscapes. <br/
A dual notion to BIBO stability
Get PDFIn this paper we consider BIBO stability of infinite-dimensional linear state-space systems and the related notion of L1-to-L1 input-output stability (abbreviated LILO). We show that in the case of finite-dimensional input and output spaces, both are equivalent and preserved under duality transformations. In the general case, neither of these properties is satisfied, but BIBO and LILO stability remain dual to each other
Increasing hydrophobicity of ceramic membranes by post-deposition nitrogen annealing of molecular layer deposition grown hybrid layers
Get PDFMolecular layer deposition is increasingly used to functionalize the surface of planar and 3D porous substrates. This study explores functionalized ‘alucone’ hybrid layers grown on ceramic substrates to enhance their surface hydrophobicity. The layers were made from trimethyl-aluminum as a precursor with five different alcohols as a co-reactant: aliphatic (ethane-1,2-diol, 2,2-oxydiethanol, 1,6-hexanediol), and aromatic (4-aminophenol, benzene-1,4-diol). After post-deposition annealing in N2 atmosphere at 250 and 350 °C, the changes in the physical properties and the chemical affinity of the layers were studied and compared to those of the as-deposited hybrid layers. Differential thermal analysis of the hybrid layers showed higher decomposition temperatures for the layers grown from aromatic alcohols than for those grown from aliphatic alcohols. Additionally, Fourier-transform infrared and X-ray photoelectron spectroscopy showed that an increase in annealing temperature decreased the concentrations of surface hydroxyl-groups and caused changes in the carbon-related groups. These results could be correlated to the hydrophobicity of the layers: higher water contact angles (>90°) were measured for annealed samples, compared to those (<90°) of the as-deposited samples grown at 150 °C. These findings confirm that the proposed method of MLD functionalization and post-deposition annealing can be used to tune the surface hydrophobicity of ceramic membranes.</p