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Extremely-to-very preterm birth and being small for gestational age increase the risk of severe airflow obstruction in patients with asthma
No full textBackground: Severity of airflow obstruction in patients with asthma can be influenced by features beyond lung function impairment. The aim of this study was to assess the severity of obstruction according to the 2022 European Respiratory Society/American Thoracic Society standards, and its associations with perinatal factors, as well as potential interactions with background and clinical factors. Methods: The study population consisted of 44,394 patients with asthma, aged 7–49 years, with at least one measurement of forced expiratory volume in 1 s (FEV1) and forced vital capacity (FVC) recorded in the Swedish National Airway Register in 2014–2022, who were included in the Medical Birth Register between 1973 and 2015 with data on gestational age (GA) and birthweight. Airflow obstruction was defined as pre-bronchodilator FEV1/FVC < lower limit of normal and categorized as mild, moderate, or severe based on FEV1z-score. Normal FEV1served as the reference category. Results: Among 7873 (17.7 %) patients with airflow obstruction, the prevalence of severe obstruction pre-bronchodilator was 6.1 %. Patients born extremely-to-very preterm or small for GA (SGA) had increased relative risk ratios for severe obstruction pre-bronchodilator (RRRadj2.34, 95 % CI 1.24–4.41, and 2.03, 1.38–2.98) compared with those born at term and appropriate for GA, respectively, with obstruction and normal FEV1. For GA and birthweight, there were non-significant interactions with background or clinical factors. Conclusions: Severe obstruction was prevalent in children and adults with asthma. Patients born extremely-to-very preterm or SGA exhibited a significant association with severe obstruction pre-bronchodilator, regardless of background and clinical factors
Long-term evaluation of periprosthetic bone changes in ultra-short versus conventional stems in total hip arthroplasty : a 10-year follow-up of a randomised controlled trial
No full textBACKGROUND: Short stems in total hip arthroplasty (THA) have the potential to improve periprosthetic bone preservation compared to conventional stems due to a more anatomical distribution of biomechanical force. This study is a follow-up study of a randomised controlled trial using ultra-short and conventional stems in THA with the aim to investigate the long-term changes in periprosthetic bone mineral density (BMD) at 6 and 10 years post-THA. METHODS: A cohort of 51 patients with hip osteoarthritis were randomized to either an ultra-short stem (n = 26) or a conventional stem (n = 25) group. Periprosthetic BMD was measured at 6- and 10-years post-surgery. Primary endpoint was BMD changes in Gruen zones 1 and 7. Lumbar spine, L1-4, BMD was used as an indicator of overall bone loss. Clinical outcome scores and BMD changes in Gruen zone 1-7 were used as secondary endpoints. RESULTS: 37 hips, 17 ultra-short stems and 20 conventional stems, were followed up until 10 years. At 6- and 10-years post-THA, the ultra-short stem group had less periprosthetic BMD reduction compared to the conventional stem group in Gruen zone 1; mean differences (%) were -17.6 (CI, -23.4--10.6) and -18.3 (CI, -28.0--9.0), respectively (p < 0.001). There was similar BMD loss in Gruen zone 7 and zones 1-7 between groups. Compared to overall bone loss, the ultra-short stem group lost less BMD than the conventional group. Adverse events and clinical outcomes did not differ between groups. CONCLUSIONS: Over a 10-year follow-up, THA using an ultra-short stem exhibited significantly reduced periprosthetic BMD loss in Gruen zone 1 compared to the conventional stem but this did not result in better clinical results. The observed preservation of bone density suggests potential long-term advantages of the ultra-short stem in minimising stress shielding and maintaining periprosthetic bone quality. TRIAL REGISTRATION: ClinicalTrials.gov registration (number NCT01319227)
A promised land? Third summary of the research program
No full textThis research note contains the third update of the research program “A promised land? Drivers, challenges and opportunities related to the (green) industrialization of Northern Sweden,” (nr. M22-0029) awarded by the Swedish Riksbankens Jubileumsfond’s in 2022. The document summarizes work in progress and is updated annually in different versions according to the requirements of the program. This interdisciplinary program aims to understand the economic, social, and political challenges and opportunities of the ongoing industrial transformation in northern Sweden. A key element of the program is to identify drivers, obstacles, and preconditions in a historical, present, and forward-looking process-perspective.
Defining the use of special educational needs documentation : positionings of preschool principals
No full textPreschools in Sweden are facing increasing requirements for introducing quality systems, and documentation practices are becoming a central part of the preschools’ work. This article examines how Swedish principals perceive the assignment of documentation regarding special educational needs (SEN). Drawing on the theoretical work of Schön, this study explores how preschool principals describe the purpose and value of SEN documentation and their own role in its practice. The findings suggest three positions towards SEN documentation, described as: Resisting, which questions the purpose of the documentation and its target group; Accepting, where documentation is used as a useful administrative tool and for structuring working practices; and, an Enthusiastic position, highlighting the benefits of documentation for individual children, staff members, and the organisation. The findings indicate that principals have a large scope for autonomy to shape and use different types of professional knowledge, which reflects different articulations of the best interests of children
"It will take time" : visual arts teachers’ professional freedom in policy enactment
No full textThe paper aims to add to what is known about how contextual prerequisites and governance systems affect art teachers’ professional freedom, a topic of global significance. Previous research shows that Visual Arts education has not been aligned with current syllabi. This discrepancy is partly explained by ‘a lag’ in the teachers’ subject conceptions given that visual arts teachers traditionally enjoy considerable professional freedom while designing their teaching. That is only one explanation; in contrast, this article, set in the Swedish educational context, enhances understanding of policy enactment in the visual art subject, with relevance for global educational policies. To understand how contextual conditions and patterns of governance determine the level of teacher autonomy, in-depth semi-structured interviews with ten art teachers in the Swedish 9-year compulsory school were conducted over 10 months in 2022, coinciding with the implementation of a new curriculum. In addition, staff from the National Agency for Education (NAfE) were interviewed, and NAfE materials were analyzed. Employing policy enactment theory, the analysis shows that contextual factors significantly influence the prerequisites of policy enactment. Further, the goals- and results-based management of schools challenges art teachers’ professional freedom as teachers adapt to the principles of governmentality. This, in turn, makes enacting new art policy challenging and time-consuming
(Re)asserting organization as a lens in sport sociology : the meaning, workings, and consequences of rational design efforts
No full textThe purpose of this article is to (re)assert the importance of an organizational lens in the socio-cultural study of sport. Specifically, we aim to demonstrate the often self-perpetuating and always value-infused nature of rational design, and the organizational processes through which problems, objectives, structures, roles, identities, and knowledges are (re)constituted in the context of sport. Drawing on an institutional understanding of organizational life, we examine Swedish sport's adoption of a new integrity platform as a case of rational design. Analyzing documentary and interview data, we demonstrate how positing organization as the object of knowledge allows us to unpack how, why, and with what effects, social issues and domains because subsumed into processes of rationalization and rational organizational design.
MLOps for cyber-physical production systems : challenges and solutions
No full textMachine Learning Operations (MLOps) involves software development practices for Machine Learning (ML), including data management, preprocessing, model training, deployment, and monitoring. While MLOps have received significant interest, much less work has been published addressing MLOps in industrial production settings lately, particularly if solutions are not cloud-based. This article addresses this shortcoming based on our and our partner&#x2019;s real industrial experience in various projects. While there is a broad range of challenges for MLOps in cyber-physical production systems (CPPS), we focus on those related to data, models, and operations as we assume these will directly benefit the reader and provide solutions such as lightweight integration, integration of domain knowledge, periodic calibration, and interactive interfaces. In this way, we want to support practitioners in setting up industrial MLOps environments in CPPS. Further, we discuss explainability as an additional part of MLOps, which should be explored in more detail in the future
Matrix discrepancy and the log-rank conjecture
No full textGiven an m×n binary matrix M with |M|=p·mn (where |M| denotes the number of 1 entries), define the discrepancy of M as disc(M)=maxX⊂[m],Y⊂[n]||M[X×Y]|-p|X|·|Y||. Using semidefinite programming and spectral techniques, we prove that if rank(M)≤r and p≤1/2, then (Formula presented.) We use this result to obtain a modest improvement of Lovett’s best known upper bound on the log-rank conjecture. We prove that any m×n binary matrix M of rank at most r contains an (m·2-O(r))×(n·2-O(r)) sized all-1 or all-0 submatrix, which implies that the deterministic communication complexity of any Boolean function of rank r is at most O(r)
Diatom dynamics during the last six centuries in Lake Odensjön : a new varved sediment record from southern Sweden
No full textVarved lake sediments offer valuable insight into past environmental conditions with high temporal resolution and precise chronological control. A combination of diatom and geochemical analyses of the recently deposited sediments of Odensjön, a small dimictic lake in southern Sweden, shows alternating light and dark laminae composed of greater amounts of biogenic silica and organic matter, respectively. As confirmed by independent radiometric dating and Pb pollution data, and supported by scanning electron microscopy of individual laminae, these features represent ongoing deposition of biogenic varves. Corresponding diatom and geochemical data obtained from a 92-cm long freeze core provide evidence of substantial lake-ecosystem dynamics during the last six centuries, related mainly to variations in light penetration and wind shear driven by human-induced changes in catchment vegetation. The diatom assemblage of Odensjön’s varved sediments is dominated by planktonic species, primarily Asterionella formosa, Fragilaria saxoplanktonica and Discostella lacuskarluki during periods of forest cover, while increased catchment openness from the mid-1500s to the late 1800s led to increased abundance of Lindavia comensis. Long-term variations in climate and land use, mediated through changing length of the ice-cover season and nutrient input, respectively, probably contributed to the observed trends, as well as to variations in the appearance and visibility of the varve record across the sampled sediment sequence. Odensjön represents the southernmost varved sediment record in Fennoscandia documented to date, offering potential to study the effects of various types of external forcing on its sensitive lacustrine ecosystem since the Late Weichselian deglaciation. In the present study, we investigated the possibility of assessing the local impacts of two major, historically documented volcanic events, Laki 1783–84 and Tambora 1815, which are known to have affected European societies. Although the mildly alkaline waters of the lake are well buffered and hence relatively resilient to volcanic acid deposition, a minor response to the Laki eruption may be recorded in the diatom stratigraphy