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BACKGROUND: The delineation of intraprostatic lesions is vital for correct delivery of focal radiotherapy boost in patients with prostate cancer (PC). Errors in the delineation could translate into reduced tumour control and potentially increase the side effects. The purpose of this study is to compare PET-based delineation methods with histopathology. MATERIALS AND METHODS: The study population consisted of 15 patients with confirmed high-risk PC intended for prostatectomy. [68Ga]-PSMA-PET/MR was performed prior to surgery. Prostate lesions identified in histopathology were transferred to the in vivo [68Ga]-PSMA-PET/MR coordinate system. Four radiation oncologists manually delineated intraprostatic lesions based on PET data. Various semi-automatic segmentation methods were employed, including absolute and relative thresholds, adaptive threshold, and multi-level Otsu threshold. RESULTS: The gross tumour volumes (GTVs) delineated by the oncologists showed a moderate level of interobserver agreement with Dice similarity coefficient (DSC) of 0.68. In comparison with histopathology, manual delineations exhibited the highest median DSC and the lowest false discovery rate (FDR) among all approaches. Among semi-automatic approaches, GTVs generated using standardized uptake value (SUV) thresholds above 4 (SUV > 4) demonstrated the highest median DSC (0.41), with 0.51 median lesion coverage ratio, FDR of 0.66 and the 95th percentile of the Hausdorff distance (HD95%) of 8.22 mm. INTERPRETATION: Manual delineations showed a moderate level of interobserver agreement. Compared to histopathology, manual delineations and SUV > 4 exhibited the highest DSC and the lowest HD95% values. The methods that resulted in a high lesion coverage were associated with a large overestimation of the size of the lesions.

Objective: PET/CT and multiparametric MRI (mpMRI) are important diagnostic tools in clinically significant prostate cancer (csPC). The aim of this study was to compare csPC detection rates with [68Ga]PSMA-11-PET (PSMA)-PET, [11C] Acetate (ACE)-PET, and mpMRI with histopathology as reference, to identify the most suitable imaging modalities for subsequent hybrid imaging. An additional aim was to compare inter-reader variability to assess reproducibility. Methods: During 2016–2019, all study participants were examined with PSMA-PET/mpMRI and ACE-PET/CT prior to radical prostatectomy. PSMA-PET, ACE-PET and mpMRI were evaluated separately by two observers, and were compared with histopathology-defined csPC. Statistical analyses included two-sided McNemar test and index of specific agreement. Results: Fifty-five study participants were included, with 130 histopathological intraprostatic lesions >0.05 cc. Of these, 32% (42/130) were classified as csPC with ISUP grade ≥2 and volume >0.5 cc. PSMA-PET and mpMRI showed no difference in performance (P = 0.48), with mean csPC detection rate of 70% (29.5/42) and 74% (31/42), respectively, while with ACE-PET the mean csPC detection rate was 37% (15.5/42). Interobserver agreement was higher with PSMA-PET compared to mpMRI [79% (26/33) vs 67% (24/38)]. Including all detected lesions from each pair of observers, the detection rate increased to 90% (38/42) with mpMRI, and 79% (33/42) with PSMA-PET. Conclusion: PSMA-PET and mpMRI showed high csPC detection rates and superior performance compared to ACE-PET. The interobserver agreement indicates higher reproducibility with PSMA-PET. The combined result of all observers in both PSMA-PET and mpMRI showed the highest detection rate, suggesting an added value of a hybrid imaging approach.

It is known that high-fat diet (HFD) and/or diabetes may influence substrate preferences and energy demands in the heart preceding diabetic cardiomyopathy. They may also induce structural glomerular changes causing diabetic nephropathy. PET/CT has been utilized to examine uptake of energy substrates, and to study metabolic changes or shifts before onset of metabolic disorders. However, conventional PET/CT scanning of organs with relatively low uptake, such as the kidney, in small animals in vivo may render technical difficulties. To address this issue, we developed a PET/CT ex vivo protocol with radiolabeled glucose and fatty acid analouges, [18F]FDG and [18F]FTHA,to study substrate uptake in mouse kidneys. We also aimed to detect a possible energy substrate shift before onset of diabetic nephropathy. The ex vivo protocol reduced interfering background as well as interindividual variances. We found increased uptake of [18F]FDG and [18F]FTHA in kidneys after HFD, compared to kidneys from young mice on standard chow. Levels of kidney triglycerides also increased on HFD. Lipoprotein lipase (LPL) activity, the enzyme responsible for release of fatty acids from circulating lipoproteins, is normally increased in postprandial mice kidneys. After long-term HFD, we found that LPL activity was suppressed, and could therefore not explain the increased levels of stored triglycerides. Suppressed LPL activity was associated with increased expression of angiopoietin-like protein4, an inhibitor of LPL. HFD did not alter the transcriptional control of some common glucose and fatty acid transporters that may mediate uptake of [18F]FDG and [18F]FTHA. Performing PET/CT ex vivo reduced interfering background and interindividual variances. Obesity and insulin resistance induced by HFD increased the uptake of [18F]FDG and [18F]FTHA and triglyceride accumulation in mouse kidneys. Increased levels of [18F]FDG and [18F]FTHA in obese insulin resistant mice could be used clinically as an indic

A common observation in fMRI studies using the BOLD signal is that older adults, compared with young adults, show overactivations, particularly during less demanding tasks. The neuronal underpinnings of such overactivations are not known, but a dominant view is that they are compensatory in nature and involve recruitment of additional neural resources. We scanned 23 young (20-37 years) and 34 older (65-86 years) healthy human adults of both sexes with hybrid positron emission tomography/MRI. The radioligand [18F]fluoro-deoxyglucose was used to assess dynamic changes in glucose metabolism as a marker of task-dependent synaptic activity, along with simultaneous fMRI BOLD imaging. Participants performed two verbal working memory (WM) tasks: one involving maintenance (easy) and one requiring manipulation (difficult) of information in WM. Converging activations to the WM tasks versus rest were observed for both imaging modalities and age groups in attentional, control, and sensorimotor networks. Upregulation of activity to WM-demand, comparing the more difficult to the easier task, also converged between both modalities and age groups. For regions in which older adults showed task-dependent BOLD overactivations compared with the young adults, no corresponding increases in glucose metabolism were found. To conclude, findings from the current study show that task-induced changes in the BOLD signal and synaptic activity as measured by glucose metabolism generally converge, but overactivations observed with fMRI in older adults are not coupled with increased synaptic activity, which suggests that these overactivations are not neuronal in origin.

Transformation av yrkeskunnande till ett undervisningsinnehåll behandlas i denna studie. I fokus är hur svetslärare synliggör ljud och hörselintryck i förhållande till lärandeobjektet ’inställningar av strömkällan i svetsmetoden MIG/MAG’, samt hur elevers förståelse kan uppvisas i undervisningen. Det saknas både praktiknära studier och ämnesdidaktisk forskning i det forskningsfält som behandlar yrkesutbildning. Syftet är därför att bidra med kunskap om vad som händer när svetslärare i en learning study systematiskt transformerar yrkesämneskunskap i undervisning av ett lärandeobjekt i svetsmetoden MIG/MAG. Empirin består av dokumenterade lärarlagssamtal och filmade undervisningspass. Resultaten påvisar yrkesämnesdidaktikens komplexitet och däri görs kopplingar till ett yrkeskunnandes transformation till ett undervisningsinnehåll., Transformation of welding teachers’ vocational knowing into subject-specific educational content is focused in this study. The article displays the process of a learning study, in which welding teachers make the sound visible as an aspect of making the correct settings in MIG/MAG welding and give the students’ the opportunity to display their understanding in the interaction. The aim of the study is to contribute with knowledge regarding what happens when welding teachers in a learning study systematically transform subject-specific vocational knowledge to an object of learning in the welding method MIG/MAG. The data consists of the welding teacher team’s documented meetings and film material from teaching situations. The complexity of subject-specific education within VET is shown with the use of the transformation concept., Konsten att lära sig svetsa (Skolfi)

Research regarding classroom pedagogy of subject specific contents in the field of technical vocational education is scarce, nationally in Sweden, but also in an international perspective. This paper presents results from a Swedish action research project and it aims at exploring the process of a learning study, which deals with the settings in MIG/MAG welding and the intervention of the new pedagogic approach CAVTA (Conversation Analysis and Variation Theory Approach). The empiric material consists of video recorded welding education in a workshop and documented meetings in a welding teacher team. The theoretical toolbox of CAVTA permeates the teaching and learning processes as the teachers in the intervention try to implement patterns of variation in the planning, enactment and evaluation of the teaching and learning processes. In combination with the variation theoretic principles embedded in the teaching, ideas inspired by conversation analysis are implemented – the main element being an enhanced interaction, thus enabling for the students to display their understanding of the subject specific contents. The results show how CAVTA can be integrated in the teaching of settings regarding MIG/MAG welding, so that certain aspects of the object of learning is visualized. Furthermore, the findings show how the integration of CAVTA support the manifestation of a student’s understanding of the object of learning. How variation and the use of several senses and simultaneous different semiotic resources are activated as essential components in the teaching and learning processes, is made explicit in the paper. Plans for a recently launched research project including several different technical vocational education programs are also presented. The lack of classroom studies regarding technical vocational education calls for exploration in research, but should not avoid the ambition of development. This study captures the design and the development of a new pedagogic approach, Konsten att lära sig svetsa

Föreliggande licentiatuppsats är en yrkesämnesdidaktisk studie som behandlar praktiska lärandemoment på det industritekniska programmet, med inriktning svetsteknik. Det övergripande syftet med licentiatuppsatsen är att bidra med kunskap om undervisnings- och lärandeprocesser när lärare systematiskt transformerar ämnesinnehåll och yrkeskunnande till svetsundervisning. Faktorer som påverkar undervisning av praktiska moment i svetsteknik behandlas med stöd av begreppet transformation och i studien utforskas hur svetslärare kan synliggöra lärandeobjekt och stimulera elevers uppvisande av förståelse och färdigheter i undervisningssituationer av praktiska moment. Studien har samlat empiri från ett praktiknära forskningsprojekt som har vilat på det teoretiska ramverket CAVTA, en kombination av samtalsanalys och variationsteori. Projektet har designats med inspiration av learning study. Olika perspektiv av det övergripande syftet behandlas i de två delstudier som innefattas i licentiatuppsatsen. Delstudie 1 utforskar undervisnings- och lärandeprocessen när svetslärare dels transformerar ämnesinnehåll och yrkeskunnande genom synliggörande av ljud och hörselintryck i förhållande till lärandeobjektet, inställningar av utrustningen i svetsmetoden MIG/MAG, dels stimulerar elever att uppvisa förståelse och färdigheter av undervisningsinnehållet i undervisningspassens interaktion. Delstudie 2 behandlar synliggörande av ett lärandeobjekt och elevers uppvisande av förståelse och färdigheter i svetsmetoden TIG. Denna delstudie fokuserar användandet av CAVTA och modellen learning study i teknisk yrkesutbildning. I resultaten framträder hur ett ämnesinnehåll, som är vagt definierat i kursplaner, bland annat genom svetslärares yrkeskunnande transformeras till undervisning av praktiska moment i svetsteknik. Studien visar hur undervisningen systematiskt utvecklas med stöd i det teoretiska ramverket CAVTA och ansatsen learning study. Ett snävt urval av lärandeobjekt och ett tydligt avg, This licentiate thesis focuses on the pedagogy of practical objects of learning in technical vocational education. The overarching aim of the thesis is to contribute with knowledge of teaching and learning processes when welding teachers systematically transform subject specific contents and vocational knowing to teaching sessions in welding. With the use of the concept transformation, aspects which impact the welding education are highlighted. The thesis explores how welding teachers can visualize practical objects of learning and encourage students to display their comprehension and abilities in the teaching situations of practical objects of learning. The data has been collected from a practice-based research project, where the approach CAVTA, a combination of conversation analysis and variation theory, has served as the theoretical framework. A modified version of the learning study model has been used to develop the teaching and learning processes of practical welding education at an upper-secondary school in Sweden. Different perspectives of the overarching aim surface in the two studies included in the thesis. The first study explores the teaching and learning processes when welding teachers transform subject specific contents and vocational knowing to welding teaching sessions of MIG/MAG welding. The variation of sound in relation to the object of learning, the settings of the equipment, is manifested in this study, as is the way the teacher in the interaction encourages the students to display their comprehension and abilities to set the equipment adequately. The second study deals with a practical object of learning in the welding method TIG. Variation and interaction in the teaching and learning processes are explored in this study as well with a focus on the use of CAVTA and the learning study model. In the findings, it is manifested how the vaguely defined subject specific contents of the curriculum, via the vocational knowing of the welding teachers, Hur allt smälter samman i handlingens centrum är en yrkesämnesdidaktisk studie som behandlar praktiska lärandemoment i svetsundervisning. Undervisnings- och lärandeprocesser när lärare systematiskt transformerar ämnesinnehåll och yrkeskunnande till svetsundervisning utforskas i denna licentiatuppsats. I studien framträder hur svetslärare i transformationsprocessen kan synliggöra undervisningsinnehåll och stimulera elevers uppvisande av förståelse och färdigheter i undervisningssituationer av praktiska moment. Resultaten visar hur undervisningen systematiskt utvecklas med stöd i det teoretiska ramverket CAVTA och ansatsen learning study. Ett snävt urval av undervisningsinnehåll och ett tydligt avgränsat fokus ger läraren möjlighet att i variation synliggöra olika aspekter av vad som ska läras. Den enskilde eleven ges på olika sätt möjlighet att uppvisa förståelse och färdigheter i undervisningssituationens interaktion. Studien riktar sig framför allt till yrkesverksamma och blivande svetslärare, men teori- och metodutvecklande bidrag kan också vara av intresse för lärare i andra yrkesutbildningar. I ett än vidare perspektiv av undervisning, lärande och pedagogiskt arbete kan utforskandet av handlingens centrum – undervisningssituationen – bidra med stimulerande tankegods åt lärarutbildare och ämnesdidaktiska forskare., Konsten att lära sig svetsa