Multiple Case Research Articles

A graph theory-based solution method for capacitor bank and voltage regulator allocation problems in an unbalanced distribution system

This paper presents a graph theory-based method to solve voltage and reactive power (voltage/var) control problems for a three-phase unbalanced distribution system (UDS). Multi-point fixed and switched capacitor bank (CB), solar distributed generation (SDG) and voltage regulator (VR) location are determined by simple and straightforward graph theory-based measures. The main contribution of this paper is – a single-stage optimisation-based voltage/var control method for UDS unlike commonly used two-stage optimisation methods; to find the location and optimal size of the CB. As the proposed graph theory method used power flow outputs to determine the most suitable nodes for CB and SDG connection, optimisation is needed only for optimal sizing at a certain location which reduces the computational burden. Secondly, optimal placement of VR is used to maintain the voltage level/voltage unbalance of the system. Multiple test cases with optimal configurations of switched CBs and optimal power factor operation-based SDG are used to demonstrate the effectiveness of proposed optimal operation techniques for overall improvement of performance parameters of UDS.

Plasma proteomic profiles of UK Biobank participants with multiple sclerosis.

We aimed to describe plasma protein biomarkers of multiple sclerosis risk and to explore protein biomarkers of disease severity using radiological outcome measures. Multiple sclerosis cases and controls were identified in UK Biobank, a longitudinal cohort study of ~500,000 British adults. Plasma proteins were assayed in ~50,000 UK Biobank participants using the Olink proximity extension assay. We performed case-control association testing to examine the association between 2911 proteins and multiple sclerosis, using linear models adjusted for confounding covariates. Associations with radiological lesion burden and brain volume were determined in a subset of the cohort with available magnetic resonance imaging, using normalized T2-hyperintensity volume or whole brain volume as the outcome measure. In total, 407 prevalent multiple sclerosis cases and 39,979 healthy controls were included. We discovered 72 proteins associated with multiple sclerosis at a Bonferroni-adjusted p value of 0.05, including established markers such as neurofilament light chain and glial fibrillary acidic protein. We observed a decrease in plasma Granzyme A, a marker of T cell and NK cell degranulation, which was specific to multiple sclerosis. Higher levels of plasma proteins involved in coagulation were associated with lower T2 lesion burden and preserved brain volume. We report the largest plasma proteomic screen of multiple sclerosis, replicating important known associations and suggesting novel markers, such as the reduction in granzyme A. While these findings require external validation, they demonstrate the power of biobank-scale datasets for discovering new biomarkers for multiple sclerosis.

Stereotactic radiotherapy of intracranial tumor beds on a ring-mounted Halcyon LINAC.

This study sought to evaluate the feasibility and efficacy of the Halcyon Ring Delivery System (RDS) for delivering stereotactic radiotherapy (SRT) treatments for intracranial tumors beds. Ten previously treated brain SRT patients for 30Gy in five fractions with non-coplanar HyperArc plans on TrueBeam (6MV-FFF) were replanned on Halcyon (6MV-FFF) using the same number of arcs and Eclipse's AcurosXB dose engine. Plan quality evaluation metrics per SRT protocol included: PTV coverage, GTV dose (minimum and mean), target conformity indices (CI), heterogeneity index (HI), gradient index (GI), maximum dose 2cm away from the PTV (D2cm), and doses to organs-at-risk (OAR). Additionally, patient-specific quality assurance (QA) results and beam-on-time (BOT) were analyzed. The Halcyon RDS provided highly conformal SRT plans for intracranial tumor beds with similar dose to target. When benchmarked against clinically delivered HyperArc plans, target coverage, CI(s) and HI were statistically similar. The Halcyon plans saw no statistical difference in maximum OAR doses to the brainstem, spinal cord, and cochlea. Due to the machine's coplanar geometry, the Halcyon plans showed a decrease in optic pathway dose (0.75Gy vs. 2.08Gy, p=0.029). Overall, Halcyon's coplanar geometry resulted in a larger GI (3.33vs. 2.72, p=0.008) and a larger D2cm (39.59%vs. 29.07%, p<0.001). In this cohort, multiple cases had the PTV and the optic pathway in the same axial plane. In one such instance, the PTV was<2cm away from the optic pathway but even at this close proximity OAR, Halcyon still adequately spared the optic pathway. Additionally, the Halcyon's geometry provided slightly larger amount of normal brain dose receiving 24.4Gy (8.99 cc vs. 7.36 cc) and 28.8Gy (2.9 cc vs. 2.5 cc), although statistically insignificant. The Halcyon plans achieved similar delivery accuracy, quantified by patient-specific QA results evaluated with a 2%/2mm gamma criteria (99.42%vs. 99.70%). For both plans, independent Monte Carlo second checks calculation agreed within 1%. Average Halcyon BOT was slightly higher by 0.35min (p=0.045), however, due to the one-step patient set-up and verification overall estimated treatment times on Halcyon were lower compared to HyperArc treatments (7.61min vs. 10.26min, p<0.001). When benchmarked against clinically delivered HyperArc treatments, the Halcyon brain SRT plans provided similar plan quality and delivery accuracy but achieved faster overall treatment times. We have started treating select brain SRT patients on the Halcyon RDS for patients having tumor beds greater than 1cm in diameter with the closest OAR distance of greater than 2cm away from the target. We recommend other clinics to consider commissioning SRT treatments on their Halcyon systems-allowing including remote Halcyon-only clinics to provide exceptionally high-quality therapeutic brain SRT treatments to an otherwise underserved patient cohort.

A modular synthesis approach for the coordination of multi-agent systems: the multiple team case

A modular synthesis approach for the coordination of multi-agent systems: the multiple team case

Mapping Hierarchical File Structures to Semantic Data Models for Efficient Data Integration into Research Data Management Systems

Although other methods exist to store and manage data in modern information technology, the standard solution is file systems. Therefore, keeping well-organized file structures and file system layouts can be key to a sustainable research data management infrastructure. However, file structures alone lack several important capabilities for FAIR data management: the two most significant being insufficient visualization of data and inadequate possibilities for searching and obtaining an overview. Research data management systems (RDMSs) can fill this gap, but many do not support the simultaneous use of the file system and RDMS. This simultaneous use can have many benefits, but keeping data in RDMS in synchrony with the file structure is challenging. Here, we present concepts that allow for keeping file structures and semantic data models (in RDMS) synchronous. Furthermore, we propose a specification in yaml format that allows for a structured and extensible declaration and implementation of a mapping between the file system and data models used in semantic research data management. Implementing these concepts will facilitate the re-use of specifications for multiple use cases. Furthermore, the specification can serve as a machine-readable and, at the same time, human-readable documentation of specific file system structures. We demonstrate our work using the Open Source RDMS LinkAhead (previously named “CaosDB”).

Fostering circular economy through open innovation: Insights from multiple case study

AbstractThis study represents an empirical, comprehensive investigation of two different inter‐organisational collaborative approaches, offering a novel perspective on collaborative circular business models in the modern economy. In this vein, we explore how open innovation strategies foster the implementation of circular economy practices within a circular supply chain and a circular ecosystem. In addition, we identify and characterise stakeholders' roles in facilitating the translation of circular principles into a viable business. An inductive theorising approach was employed, leveraging an explorative multiple case study methodology. Data were collected from 13 organisations involved in two collaborative networks, designed to establish upcycling practices to recover waste from the food and beverage industry. A critical realist philosophical positioning underpinned researchers' data collection and analysis. As a result, we outline the nature of two different collaborative approaches to pursue a regenerative production system through open innovation strategies: a circular supply chain and a circular ecosystem architecture. The characterisation of the coordinator and orchestrator of collaborative circular business models is also highlighted in our findings. In sum, this study contributes to the literature on circular economy by unveiling the role of open innovation in fostering circular business development. From a practical standpoint, it offers insights for managers of sustainability‐oriented companies willing to implement upcycling practices.

Nexus of circular economy R0 to R9 principles in integrated reporting: Insights from a multiple case study comparison

AbstractOver recent years, the Circular Economy (CE) has turned into a debated area worldwide as a way of achieving a more sustainable society. However, little is known about how companies can disclose CE‐related activities in their corporate reporting. This paper aims to explore how and to what extent CE‐related information is included in Integrated Reporting (IR) practices by promoting Sustainable Development Goals (SDGs). The study applies qualitative content analysis and thematic analysis approaches to explore the associations with CE, IR, the six capitals and SDGs. The institutional theory approach has been adopted to justify incorporating CE R‐principles activities into IR practices. Multiple case study findings demonstrate that every case company minimum one time cites the CE R principle, while case companies seen to be more involved in the reduce (R1), reuse (R2) and recycle (R7) are engaged with IR practices and focussing on SDGs. Whereas coercive, normative, and mimetic isomorphism mechanism substantially impacts CE activities concerning IR practices, we can argue that mimetic isomorphisms need further investigation because no structures and frameworks are available. In terms of managerial implications, this study proposed a combined framework of CE and IR that provides a conceptual picture of how CE activities intermesh with the IR framework and the six capitals, both essential for the Sustainable Development (SD) agenda participation and value creation process of companies.

Developing interactive pedagogies: A case of accounting pre-service teachers from Ghana

This is a study of how eight pre-service teachers developed their skills in developing interactive lessons to teach concepts in Accounting in Senior High Schools in Ghana. Sequential multiple case study design was employed to observe two cohorts of four pre-service teachers who worked in two phases of a professional development scenario to design and enact interactive Accounting lessons. Data for the study were collected through observation, interviews, lesson documents and questionnaires. Pictures, content and thematic analysis procedures were used to analyse the qualitative data, whilst means and standard deviation were used to analyse the quantitative data. It emerged from the results that the interactive lessons developed and implemented by the pre-service teachers were effective in promoting participation in the classroom. The study also brought to light that interactive teaching promotes collaboration among students through solving problems in groups which helps to strengthen the bond between students. The study thus, advocates the need for teacher training institutions to focus on training teachers to acquire the skills in designing and enacting lessons interactively to promote students’ participation in the classroom.

Evaluation of a software positioning tool to support SMEs in adoption of big data analytics

Big data analytics has been widely adopted by large companies to achieve measurable benefits including increased profitability, customer demand forecasting, cheaper development of products, and improved stock control. Small and medium sized enterprises (SMEs) are the backbone of the global economy, comprising of 90 % of businesses worldwide. However, only 10 % SMEs have adopted big data analytics despite the competitive advantage they could achieve. Previous research has analysed the barriers to adoption and a strategic framework has been developed to help SMEs adopt big data analytics. The framework was converted into a scoring tool which has been applied to multiple case studies of SMEs in the UK. This paper documents the process of evaluating the framework based on the structured feedback from a focus group composed of experienced practitioners. The results of the evaluation are presented with a discussion on the results, and the paper concludes with recommendations to improve the scoring tool based on the proposed framework. The research demonstrates that this positioning tool is beneficial for SMEs to achieve competitive advantages by increasing the application of business intelligence and big data analytics.

Women leaders' lived experiences of bravery in leadership

PurposeThe research aims to understand the stories of women leaders who have demonstrated bravery in leadership. By analyzing their lived experiences through storytelling and narratives, it seeks to shed light on the challenges and motivations behind their brave actions, contributing to a deeper understanding of bravery in leadership within gender and organizational contexts.Design/methodology/approachThis study adopts a qualitative multiple case study approach, focusing on the autobiographical accounts of three women leaders to explore their experiences of bravery in leadership. Utilizing narrative analysis (NA), it is grounded in ethical leadership theory and narrative identity theory. The research method involves cross-analyzing these narratives to unearth themes that depict a multifaceted view of bravery, including moral courage and ethical decision-making.FindingsThe study reveals various themes of bravery in leadership, such as moral courage, authenticity, resilience and ethical decision-making. These findings enhance the understanding of bravery's role in ethical conduct and transformative change, highlighting the complex manifestations of bravery in women's leadership practices.Research limitations/implicationsThis study contributes to the broader discourse on bravery in leadership, especially for women. It offers insights into how bravery is integral to ethical conduct and transformative leadership and sheds light on the influence of gender dynamics on leadership experiences. This study significantly enriches the discourse on bravery in leadership, with a particular focus on women's experiences. It delves into how bravery, encompassing moral courage and authenticity, is crucial for ethical conduct and transformative leadership. By highlighting the stories of women leaders, the research underscores the complex interplay between bravery and gender dynamics within organizational contexts. It challenges traditional perceptions of leadership and bravery, advocating for a more nuanced understanding that recognizes the unique challenges and strengths of women leaders. Furthermore, this study paves the way for future research to explore diverse dimensions of bravery in leadership, encouraging a more inclusive approach that values different perspectives and experiences.Practical implicationsThe findings of this study advocate for empowering leadership practices and guide the development of a courageous leadership landscape. Current events show evidence that many organizations lack the integration of bravery as a core leadership trait. These narratives of bravery in women's leadership can serve as a powerful catalyst for inspiring all leaders These stories can guide leaders across various levels to embrace bravery in their decision-making and leadership styles. The integration of these insights into organizational policies and leadership development programs can lead to a more courageous, ethical and transformative leadership landscape.Social implicationsThe research emphasizes the need for inclusive approaches to leadership and bravery, challenging dominant gender norms. It underscores the importance of acknowledging and valuing women leaders' stories, thereby empowering their narratives.Originality/valueThe study adds value to the field by unveiling the often untold narratives around bravery in leadership. Findings can assist in fostering environments where diverse expressions of bravery are recognized and valued. Findings have the potential to inspire a new generation of leaders, across all genders, to embrace bravery in their roles, thereby enriching the leadership landscape with diverse, ethical and courageous practices. This research not only contributes to academic discourse but also has real-world implications, encouraging organizations to reevaluate and evolve their leadership models to be more inclusive and effective in today's dynamic and diverse global environment.

MoDAFold: a strategy for predicting the structure of missense mutant protein based on AlphaFold2 and molecular dynamics.

Protein structure prediction is a longstanding issue crucial for identifying new drug targets and providing a mechanistic understanding of protein functions. To enhance the progress in this field, a spectrum of computational methodologies has been cultivated. AlphaFold2 has exhibited exceptional precision in predicting wild-type protein structures, with performance exceeding that of other methods. However, predicting the structures of missense mutant proteins using AlphaFold2 remains challenging due to the intricate and substantial structural alterations caused by minor sequence variations in the mutant proteins. Molecular dynamics (MD) has been validated for precisely capturing changes in amino acid interactions attributed to protein mutations. Therefore, for the first time, a strategy entitled 'MoDAFold' was proposed to improve the accuracy and reliability of missense mutant protein structure prediction by combining AlphaFold2 with MD. Multiple case studies have confirmed the superior performance of MoDAFold compared to other methods, particularly AlphaFold2.

CAP-RNAseq: an integrated pipeline for functional annotation and prioritization of co-expression clusters.

Cluster analysis is one of the most widely used exploratory methods for visualization and grouping of gene expression patterns across multiple samples or treatment groups. Although several existing online tools can annotate clusters with functional terms, there is no all-in-one webserver to effectively prioritize genes/clusters using gene essentiality as well as congruency of mRNA-protein expression. Hence, we developed CAP-RNAseq that makes possible (1) upload and clustering of bulk RNA-seq data followed by identification, annotation and network visualization of all or selected clusters; and (2) prioritization using DepMap gene essentiality and/or dependency scores as well as the degree of correlation between mRNA and protein levels of genes within an expression cluster. In addition, CAP-RNAseq has an integrated primer design tool for the prioritized genes. Herein, we showed using comparisons with the existing tools and multiple case studies that CAP-RNAseq can uniquely aid in the discovery of co-expression clusters enriched with essential genes and prioritization of novel biomarker genes that exhibit high correlations between their mRNA and protein expression levels. CAP-RNAseq is applicable to RNA-seq data from different contexts including cancer and available at http://konulabapps.bilkent.edu.tr:3838/CAPRNAseq/ and the docker image is downloadable from https://hub.docker.com/r/konulab/caprnaseq.

Educational inclusion for migrants and refugees through language learning: difficulties, challenges and ways forward

The teaching-learning process of languages for migrants and refugees is a challenge that goes beyond getting them to develop communication skills and moves toward inclusion through education. In order to analyze the main keys and difficulties when it comes to teaching this collective, this multiple case study selects seven European countries in whose educational contexts teachers and migrants work together. Specifically for this research, the perspectives of 35 experts were taken into account as a result of the data gathered through round tables. After developing a cross-case analysis, the results demonstrated significant connections which delved into analytical generalizations: (i) the importance of focusing on the cultural dimension and the motivation factor; (ii) the impact of structural vulnerability on students, which was identified as the main obstacle when it comes to achieving the objective of teaching, and (iii) the lack of institutional resources. Finally, (iv) active methodologies were proposed as a way forward to address these challenges.

An Exploration on Utilization of Business Analytics in Sri Lankan Banks

In this era of data evangelism, organizations are evolving with a paradigm shift from intuition-driven decision making to evidence-based decision making. Thus, business analytics has become a popular buzzword in modern business. Banking is a lavish industry that generates massive amounts of data and has copious opportunities for the utilization of business analytics to reap its maximum return. Therefore, the significance of business analytics in banking cannot be ignored. Though some international studies have indicated the utilization of business analytics in banks, studies on Sri Lankan banks are quite scarce. To fill this gap, this paper investigates the current utilization of business analytics in the Sri Lankan banking industry. The paper adopted a qualitative approach with multiple case studies, interviewing five professionals from different private commercial banks who are well-versed in business analytics. The paper covers eight aspects of business analytics utilization: duration of use, delegation, beneficiaries, technological aid, essentiality, value realization, perceived usage, and future direction. It was found that most banks have started using business analytics during the last three to four years, mainly for digital banking and card operations with basic technologies such as Power BI and Tableau. Further, it was also found that most banks have realized the importance and potentiality of business analytics, but neither integrated it fully with their core business nor achieved the expected value creation. The paper concludes that Sri Lankan banks are still in the early stages of business analytics maturity. Thus, there is a need to overcome the challenges and implement strategies to leverage business analytics for their benefit. Importantly, this study will contribute to the body of knowledge in the field of business analytics and the Sri Lankan banking industry where related studies are scarce.

Delay‐difference approximations of PD‐controllers. Improperly‐posed systems in multiple delays case

SummaryIn this paper, we study the behavior of characteristic roots of a class of strictly proper LTI SISO systems that are subject to a PD controller for which the derivative action has been implemented by means of a delay‐difference approximation scheme that uses multiple delays. To such an end, the improperly‐posed case is discussed in depth, that is, the situations where “small delays” induce instability in the closed‐loop system. The effect of adding more delays on the improperly‐posed case is analyzed and a methodology for determining the set of parameters that produces such a situation for a given number of delays is derived. Some illustrative examples complete the presentation.

Toward a dynamic capability perspective of digital transformation in SMEs: A study of the mobility sector

Digital Transformation (DT) has been considered a critical structural change for SMEs to be responsive and agile in today's dynamic and turbulent business environments. This significance is more evident in mobility and transport systems in which the sector is undergoing radical technological changes in the context of smart cities. However, SMEs must possess some capabilities to successfully leverage DT toward better performance and gain a competitive advantage. The current research is a step forward toward achieving this goal. Using a multiple case study of mobility sector SMEs in Australia, the authors explore the nature of Dynamic Capabilities (DC) in SMEs and discover digital transformation's enablers, barriers, and performance outcomes.

Uncovering the clinical relevance of unclassified variants in DNA repair genes: a focus on BRCA negative Tunisian cancer families.

Introduction: Recent advances in sequencing technologies have significantly increased our capability to acquire large amounts of genetic data. However, the clinical relevance of the generated data continues to be challenging particularly with the identification of Variants of Uncertain Significance (VUSs) whose pathogenicity remains unclear. In the current report, we aim to evaluate the clinical relevance and the pathogenicity of VUSs in DNA repair genes among Tunisian breast cancer families. Methods: A total of 67 unsolved breast cancer cases have been investigated. The pathogenicity of VUSs identified within 26 DNA repair genes was assessed using different in silico prediction tools including SIFT, PolyPhen2, Align-GVGD and VarSEAK. Effects on the 3D structure were evaluated using the stability predictor DynaMut and molecular dynamics simulation with NAMD. Family segregation analysis was also performed. Results: Among a total of 37 VUSs identified, 11 variants are likely deleterious affecting ATM, BLM, CHEK2, ERCC3, FANCC, FANCG, MSH2, PMS2 and RAD50 genes. The BLM variant, c.3254dupT, is novel and seems to be associated with increased risk of breast, endometrial and colon cancer. Moreover, c.6115G>A in ATM and c.592+3A>T in CHEK2 were of keen interest identified in families with multiple breast cancer cases and their familial cosegregation with disease has been also confirmed. In addition, functional in silico analyses revealed that the ATM variant may lead to protein immobilization and rigidification thus decreasing its activity. We have also shown that FANCC and FANCG variants may lead to protein destabilization and alteration of the structure compactness which may affect FANCC and FANCG protein activity. Conclusion: Our findings revealed that VUSs in DNA repair genes might be associated with increased cancer risk and highlight the need for variant reclassification for better disease management. This will help to improve the genetic diagnosis and therapeutic strategies of cancer patients not only in Tunisia but also in neighboring countries.

Navigating burnout: a study of teacher identity in Chile, Ecuador, Brazil, Spain and Australia

ABSTRACT A key tool amongst the strategies used by teachers to combat stress at work is the construction and development of a professional identity. The underlying idea is that professional identity has the potential to prevent or help teachers to overcome burnout, a problem that is increasingly common within the profession. We conducted a multiple case study and analysed five subjective learning experiences recounted by novel teachers working in Chile, Ecuador, Brazil, Spain and Australia. Results show that (i) teachers constantly experience scenarios that lead to stress or exhaustion and involve various negatively valenced emotional evaluations; (ii) the substitution of these evaluations is particularly relevant, as it contributes to the formation of new meanings and positions relative to the situation; (iii) this repositioning may be connected to particular objects, to the subjects themselves, or to positions within the community in question; (iv) positively valenced emotional evaluations may be substituted for negatively valenced emotional evaluations, reflecting that positional changes are not always fruitful; and (v) some emotionally valenced evaluations endure over time and are key generators of professional stress.

Are well-designed places possible? A model of design governance intervention in the planning, design and development of new neighbourhoods

ABSTRACT UK planning policies clearly state that well-designed places support the creation of sustainable places that generate positive economic, environment and social outcomes. Yet, for decades, the design value of ‘new build’ housing development has remained stubbornly low. Using data from a multiple case study of new housing developments across the UK’s four nations, this paper asks why this persists and explores how it might be overcome. It models nine key stages in the planning, design and development process for new housing illustrating where the ‘critical points of design governance intervention’ lie.

Undergraduate students’ models of single- and multi-electron atoms

ABSTRACT Quantum physics forms the basis for exciting new technologies, including quantum computers, quantum encryption, and quantum entanglement. The advancement of science and technology highlights the importance of mastering quantum physics and its applications, not only at the college level but also as early as high school. In this multiple case study, we investigated first- and second-year undergraduate college students’ models of single and multi-electron atoms after completing a modern mechanics course, which addressed basic QM topics. The students’ models were categorised into four primary categories: the discrete entity (particle) model, hybrid model, quantum-like model, and quantum model, and subcategories for atom structure and electron attribution and motion. Despite being introduced to quantum concepts in high school and first-year undergraduate calculus-based physics classes, many students constructed incomplete, inaccurate, or incoherent models. Seven of eight students’ atomic structure models and six of eight students’ electron attribution and motion models were classified as discrete entity and hybrid models. The findings of this study reveal students’ conceptual challenges in explaining the structure of single and multiple-electron atoms and shed light on the factors contributing to the persistent difficulties in their understanding of atomic structure in the realm of quantum mechanics.