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Primary caregivers' perceptions of challenges in dental and orthodontic care for children with Down syndrome
No full textIntroduction and aims Children with Down syndrome (DS) face increased oral health risks and barriers to dental care. Understanding caregivers’ perceptions about their child’s dental care is key to better outcomes. This study aimed to investigate primary caregivers’ perceptions of the dental and orthodontic care of children with DS, and the association with cooperation in encounters involving the child and dental professionals. Methods A cross-sectional study was conducted using an online questionnaire completed by 77 primary caregivers, mostly mothers, of children with DS aged 6 to 17 years. Descriptive statistics and logistic regression were used to analyse the data. Results Children with DS often needed support with toothbrushing, but were frequently reported as cooperative during home care and dental visits. Many children used alternative communication methods and had difficulty being understood. About half of the caregivers discussed their child’s needs with dental professionals in a premeeting. Fewer than half of the professionals were reported as communicating effectively with the children. Children who were perceived by their primary caregivers as cooperative during toothbrushing at home were significantly more likely to be cooperative during dental visits ( P < .05). Additionally, being referred for an orthodontic assessment was statistically associated with higher levels of cooperation during dental appointments, according to the primary caregivers ( P < .05). Conclusion Despite communication challenges, many children showed cooperation during home care and dental visits. Perceived cooperation during toothbrushing at home and being referred for an orthodontic assessment were associated with higher cooperation during dental appointments for children with DS. Enhancing dental professionals’ communication skills and using personalised care approaches may improve dental outcomes and experiences for children with DS. Clinical relevance These findings underscore the importance of tailored dental care approaches and improved communication techniques to foster active participation and better dental outcomes for children with DS
Childhood Functional Constipation : Clinical outcomes and lived experiences of Children and their Families
No full textBackground This thesis investigates the multifaceted experiences and outcomes associated with childhood functional constipation, a condition that significantly affects children’s health and family life. Drawing on one quantitative and three qualitative studies, the research provides an increased understanding of how children and families navigate the challenges of diagnosis, treatment, and daily life with a child suffering from functional constipation. Aim The overall aim was to inform a more child- and family-centred perspective to functional constipation care by exploring the experiences of parents and children, and to evaluate a clinical treatment programme. Methods Study I is a retrospective cohort review of medical records with pre-post intervention measurements. Children participating in a structured bowel management programme in a secondary outpatient clinic between 2015 and 2022 were recruited. Clinical variables were compared between the recovered and the unrecovered groups to identify predisposing characteristics and predictive factors for recovery. Studies II and III have a qualitative design, presents interviews with parents about their experiences of having a child with constipation and of giving treatment at home. The same data set of 15 parents were used for both studies. The Reflective Lifeworld Research approach originating from phenomenology was used during analysis. Study IV, also qualitative, presents interviews with 20 children aged between 6 and 14 about their experiences of having constipation and receiving treatment. Reflexive thematic analysis was used during analysis. Findings The first study demonstrates significant improvements in bowel function and symptom relief among children following the intervention. Structured care helped 44% of therapy-resistant children to reach cure or self-management abilities within six months. The study underscores the value of integrating clinical protocols with family education and support. The second study reveals how childhood constipation disrupts family routines, emotional well-being, and social interactions as treatment support requires considerable attention and strength. Parents report feelings of frustration, helplessness, and isolation, often compounded by limited support from healthcare professionals. The findings highlight the need for more empathetic child and family-centred care strategies. The third study uncovers the emotional and practical challenges involved in managing medication routines, feelings of abuse and inadequacy, while trying to maintain adherence. The study emphasises the importance of clear communication and sustained support to empower parents in their caregiving roles because they might question their parental identity. The fourth study presents the child’s perspectives on functional constipation with associated treatments. It presents a close and realistic narrative of procrastination of toilet visits, fear of exposure of leakage in social situations, rectal enemas as both awful and relieving, and hope, while striving for control. Conclusions Together these studies offer a holistic understanding of childhood functional constipation, bridging the gap between clinical outcomes and family experiences. Families deal with physical symptoms, psychological defences, fear of social judgment, and struggles with treatment. This thesis offers actionable insights for children, parents, clinicians, and researchers to improve the quality of constipation care for children and their caregivers
Deformation of surrounding rocks in salt caverns in compressed air energy storage plants: Insights from laboratory experiments and numerical simulations
No full textThe long-term mechanical stability of surrounding rock in compressed air energy storage (CAES) salt caverns is crucial for the safe and efficient operation of underground energy systems. In this study, the deformation behavior of salt rock was investigated through a combined approach that involved long-term laboratory creep–fatigue tests and engineering-scale numerical simulations. Mechanical experiments were carried out at various cyclic stress levels and loading rates to replicate the creep–fatigue loading conditions that are encountered during CAES operations. The results indicate that both the magnitude and the frequency of cyclic loading significantly influence the time-dependent deformation of salt rock: higher stress levels accelerate damage, whereas lower loading rates lead to increased plastic strain. On the basis of the geological conditions of a planned CAES facility, numerical simulations were conducted using FLAC3D. The model incorporates the Norton creep law to simulate the evolution of the surrounding rock with different numbers of operational cycles and gas pressures. The operating pressure and frequency significantly affect the deformation and plastic zone distribution of the surrounding rock in salt cavern reservoirs. Higher operational frequencies and minimum gas pressures result in reduced deformation and improved cavern stability. For the first time, a direct qualitative analysis was conducted to compare the laboratory experiments and numerical simulation results. Comparative analysis reveals that the experimental and simulation results are generally consistent. These findings offer new insights into the mechanical response of salt cavern-surrounding rock and establish a foundation for predicting the long-term performance of CAES systems.Full text license: CC BY 4.0;Funder: Rut and Sten Brand foundation; National Natural Science Fund of China (52274073); Chongqing Youth Innovative Talent Project (CSTB2024NSCQ-QCXMX0022); Chongqing Natural Science Foundation Innovation and Development Joint Fund (CSTB2024NSCQ-LZX0056); Open Research Fund of State Key Laboratory of Geomechanics and Geotechnical Engineering Safety (SKLGGES-024006)</p
Beyond linear progress : Towards a material-temporal understanding of infrastructural unmaking
No full textThe implementation of low-carbon futures requires both the assembling of new technologies, and practices, as well as the 'unmaking' of extant high-carbon infrastructures. Here, we bring together geographical, STS, anthropological, and sociological thinking on time to re-conceptualise such processes of unmaking. We argue that a focus on temporalities is especially pertinent to the unmaking of material energy infrastructure, as the emergence of fossil fuel societies has also enabled a particular temporality of the future to take hold; one that is linear, future-oriented, and full of promise. The unmaking of energy infrastructures will likely rub up against this temporal form of thinking that dominates modern life. By drawing on three temporal concepts - ruination, suspension, and lingering - we explore how we can conceptualise the temporal dimensions of unmaking material infrastructures more explicitly, and differently. Through foregrounding the multifaceted interactions between the legacies of the past, the realities of the present, and the possibilities of the future we put forward an understanding of infrastructural unmaking and lowcarbon futures that seeks to go beyond the confines of linear progress
Knowledge ecosystem emergence : Organizing participation, identity, and actorhood to bridge the governance void
No full textMulti-organizational collaborations involving the industry, academia, and government have become prevalent in developing knowledge to address complex societal problems. These fluid and loosely coupled forms of collaboration, known as knowledge ecosystems, provide the necessary organizing elements for the search and creation of new knowledge. While the literature acknowledges the prevalence of knowledge ecosystems, it remains relatively silent on how their organization develops over time. This lacuna in our understanding is problematic, given the challenge of governance voids for cross-sectoral knowledge collaborations, which lead to difficulties in mobilizing action, securing resources, and ultimately achieving the knowledge-related goals of these collaborations. To address this gap, we theorize knowledge ecosystems as meta-organizations, examining how they gradually develop organizing elements that bridge the initial governance void. Empirically, we draw on an in-depth field case study of the High-Capacity Transport ecosystem in Sweden, demonstrating how three interrelated organizational elements—participation, identity, and actorhood—emerge through an iterative, yet broadly sequential process to resolve governance void challenges in resourcing, belonging, and collective action. Furthermore, we identify discursive and performative meta-organizational practices that enable the actors to collectively enact the aforementioned organizational elements and to engage in knowledge search. We further demonstrate how the organization of knowledge ecosystems is never ‘complete’ and the governance void remains only partially resolved, given the underdefined nature of new knowledge as the ecosystem's shared goal. Overall, our process model contributes to the theory, practice, and policy of knowledge ecosystem emergence and organizing
Mechanical properties and thermal stability of refractory metal-alloyed (Al V)N-based high-entropy nitrides and oxynitrides
No full textThis study explores the thermal stability and mechanical properties of (Al,V)-based high-entropy sublattice nitride (HESN) and oxynitride (HESON) coatings alloyed with various refractory metals, including Ti, Cr, Mo, W, Hf, and Zr. Through systematic annealing treatments at 800 degrees C, we examine the influence of alloying elements on the hardness and indentation modulus of these coatings. The results show that coatings alloyed with Ti-Hf-Cr, TiHf-W, Zr-Hf-Cr, and Ti-Cr-W exhibit excellent retention of mechanical properties under prolonged thermal exposure. In particular, the Ti-Hf-W-alloyed (Al,V)N and its oxynitride variant maintain the highest hardness of similar to 32 GPa during 50 h vacuum annealing at 800 degrees C. Conversely, the Cr-Mo-W-alloyed variants exhibit significant degradation and the formation of an Me2N phase. X-ray diffraction analyses reveal changes in preferred crystallographic orientations and the emergence of fcc-structured domains, influencing mechanical behavior. Despite their thermal degradation, the Cr-Mo-W-alloyed (Al,V)N showed the most promising fracture toughness behavior. The findings highlight the importance of careful selection of alloying elements and compositions to optimize the performance of HESN and HESON coatings for high-temperature applications. This research provides valuable insights into the underlying mechanisms affecting the thermal and mechanical properties of advanced coatings, paving the way for future advancements in materials designed for extreme environments
The Enactment of the Authentic Original: Conservation-restoration of kalkmålningar in Swedish curches around 1850–1980
No full textIn Sweden, there are more than a thousand completely or partially preserved medieval churches, with many containing kalkmålningar (mural paintings), dating from between the twelfth and seventeenth centuries. This thesis deals with the enactments and re-enactments that formed the revival of these paintings, particularly the conservation-restoration work carried out between 1850–1980, including contemporaneous, decorative, and monumental paintings that were created in relation to this revival. The thesis further investigates how kalkmålningar became embedded within Sweden’s listed cultural heritage. Following the enactments, thought collectives of the period are revealed, shedding light on the relation between these paintings and the establishment of theories and practices within the emergent field of conservation-restoration. Through an eclectic methodology–including analysis of written sources, and investigations of the paintings in-situ, partly grounded on inspiration from actor-network theory (ANT), discursive analysis, posthumanism, and object-oriented ontology (OOO)–the thesis asks what agency these paintings have. How can we understand conservation-restoration as a hybrid practice that encompasses a more-than-human perspective, challenging the modern dichotomy between nature and culture? The thesis is divided into three parts. The first part gives an introduction to the thesis, theory, and method, including an analysis of the emergence of conservation-restoration in relation to the modern “thought figure” of the “authentic original”. It gives an introduction to the topic of kalkmålningar in Sweden, and an analysis of the network that enacted them and their collective values. The second part forms a historical analysis and description of the enactments of kalkmålningar between 1850–1980, identifying three periods of different conservation-restoration principles: stylistic restoration, original conservation-restoration, and precautionary conservation-restoration. The third part discusses the enactments that informed the revival of kalkmålningar, and draws conclusions concerning the ontology of conservation and paintings. This part further identifies and discusses particular traditions of Swedish restoration, such as the principles of Sigurd Curman, the precautionary attitude, the pursuit of a lively harmonic church room, the prevalence of handicraft conservation-restoration, as well as the restrictive attitude towards retouching that emerged in the 1960s, and the lack of an institute dedicated to technical studies of art. The thesis concludes with an epilogue, in which three contemporary conservation-restoration tendencies are finally discussed, influenced by a changing perception regarding ethics, sustainability, and the authentic original.I Sverige finns mer än tusen helt eller delvis bevarade medeltida kyrkor, varav många har rester av kalkmålningar från 1100-talet till 1600-talet. Den här avhandlingen behandlar hur dessa kalkmålningar framställdes och återupprättades genom konserverings- och restaureringsåtgärder omkring 1850–1980, inklusive de dekorativa och monumentala muralmålningar som tillkom i relation till kalkmålningarna. Avhandlingen undersöker också hur kalkmålningarna blev en del av det skyddade kulturarvet. Genom att följa hur målningarna framställdes synliggörs de ”tankekollektiv” som ingick i processen och den parallella etableringen av konservering som disciplin. Genom en kombination av metoder – som innefattar såväl analys av skriftligt källmaterial som undersökning av målningarna in situ, delvis grundad på inspiration från aktör-nätverksteori (ANT), diskursanalys, posthumanism och objektorienterad ontologi (OOO) – ställer avhandlingen frågan om målningarnas agens. Hur kan vi förstå konservering och restaurering som en hybrid praktik, som innefattar meränmänskliga perspektiv och utmanar den moderna dikotomin mellan natur och kultur? Avhandlingen är disponerad i tre delar. Den första delen, inledningen, introducerar avhandlingens syfte, teori och metod, och kompletteras av ett avsnitt om framväxten av konserveringen och dess förhållande till tankefiguren om det autentiska originalet. Vidare introduceras kalkmålningarna i Sverige och nätverket som framställde dem samt olika värdegemenskaper. Den andra delen utgör en historisk analys och beskrivning av hur kalkmålningarna framställdes omkring 1850–1980, disponerad utifrån tre perioder med olika, identifierade konserveringsprinciper: stilrestaureringen, originalkonserveringen och försiktighetskonserveringen. Den tredje delen diskuterar avhandlingens resultat genom att dra slutsatser om konserveringens och målningarnas ontologi och om kalkmålningarnas huvudsakliga framställningssätt. Vidare identifieras och diskuteras några svenska särdrag, däribland Sigurd Curmans principer, strävandet efter återhållsamhet och ett levande harmoniskt kyrkorum, betoningen av hantverksmässig konservering och den restriktiva inställningen till retuschering som växte fram under 1960-talet, samt avsaknaden av ett institut för konstteknologi. Avhandlingen avslutas med en epilog, där tre samtida konserveringstendenser diskuteras, påverkade av en ny syn på etik och hållbarhet, samt på det autentiska originalet.QC 20251218</p
Key events as signifiers for the 'window of opportunity' to reduce car use
No full textLife events have long been discussed as a 'window of opportunity' for promoting pro-environmental behaviors such as car use reduction. However, findings from this study suggest that it is key events, rather than life events per se, that drive the emergence of such windows of opportunity. This distinction is crucial for understanding when and how the psychological prerequisites for desirable behavior change are most likely to arise. While researchers have focused on the relation between life events, habit disruption, and behavior change, less attention has been given to how life events relate to decisive factors for deliberate decision-making. Based on a mobility biography approach and the related Framework of RoUtIne Transitions in daily travel (FRUIT), this cross-sectional study explores how periods of life events relate to the potential for, and motivation for, reducing car usage. Online survey data from a sample of Swedish car users were analyzed using group comparisons and partial least squares structural equation modeling (PLS-SEM). The findings show that changed travel routines relate to stronger motivation for car use reduction and weaker daily travel habits, regardless of whether the change being provoked by life events or triggered for other reasons. It is concluded that life events indeed are associated with the 'window of opportunity' for car use reduction; however, only when they turn into key events and hence, are interconvertible with other events triggering changes in travel routines. We advocate for a broadened perspective on the types of events that may activate preferable psychological prerequisites for reducing car use
Pediatric brain tumor classification using digital pathology and deep learning : Evaluation of SOTA methods on a multi-center Swedish cohort
No full textBrain tumors are the most common solid tumors in children and young adults, but the scarcity of large histopathology datasets has limited the application of computational pathology in this group. This study implements two weakly supervised multiple-instance learning (MIL) approaches on patch features obtained from state-of-the-art histology-specific foundation models to classify pediatric brain tumors in hematoxylin and eosin whole slide images (WSIs) from a multi-center Swedish cohort. WSIs from 540 subjects (age 8.5 ± 4.9 years) diagnosed with brain tumors were gathered from the six Swedish university hospitals. Instance (patch)-level features were obtained from WSIs using three pre-trained feature extractors: ResNet50, UNI, and CONCH. Instances were aggregated using attention-based MIL (ABMIL) or clustering-constrained attention MIL (CLAM) for patient-level classification. Models were evaluated on three classification tasks based on the hierarchical classification of pediatric brain tumors: tumor category, family, and type. Model generalization was assessed by training on data from two of the centers and testing on data from four other centers. Model interpretability was evaluated through attention mapping. The highest classification performance was achieved using UNI features and ABMIL aggregation, with Matthew's correlation coefficient of 0.76 ± 0.04, 0.63 ± 0.04, and 0.60 ± 0.05 for tumor category, family, and type classification, respectively. When evaluating generalization, models utilizing UNI and CONCH features outperformed those using ResNet50. However, the drop in performance from the in-site to out-of-site testing was similar across feature extractors. These results show the potential of state-of-the-art computational pathology methods in diagnosing pediatric brain tumors at different hierarchical levels with fair generalizability on a multi-center national dataset.Funding Agencies|Linkoeping University's Cancer Strength Area; ALF Grants, Region Ostergoetland [974566]; Vinnova via Medtech4Health and Analytic Imaging Diagnostics Arena [2222]; Swedish Childhood Cancer Fund [MT2021-0011, MT2022-0013]; Joanna Cocozza's Foundation for Children's Medical Research</p
Norm estimates for a broad class of modulation spaces, and continuity of Fourier type operators
No full textWe consider a broad class of modulation spaces M(ω, B),parameterized with weight function ω and a normal quasiBanach function space B of order r0 ∈ (0, 1]. Then we provethat f ∈ M(ω, B), if and only if Vϕf belongs to the Wieneramalgam space Wr(ω, B), and ∥f∥M(ω,B) ≍ ∥Vϕf · ω∥B ≍ ∥Vϕf∥Wr(ω,B), r ∈ [r0, ∞]. We use the results to extend and improve continuity andlifting properties for pseudo-differential and Toeplitz operatorswith symbols in weighted M∞,r0 -spaces, r0 ≤ 1, when actingon M(ω, B)-spaces