Publikationer från Uppsala Universitet
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Revisiting inelastic Cu + H collisions and the non-LTE Galactic evolution of copper
No full textThe Galactic evolution of copper remains poorly understood, partly due to the strong departures from local thermodynamic equilibrium (LTE) affecting Cu I lines. A key source of uncertainty in non-LTE modelling is the treatment of inelastic Cu + H collisions. We present new rate coefficients based on a combined asymptotic LCAO (linear combination of atomic orbitals) and free electron model approach, which show significant differences from previous calculations. Applying these updated rates to non-LTE stellar modelling, we find reduced line-to-line scatter and improved consistency between metal-poor dwarfs and giants. Our non-LTE analysis reveals a strong upturn in the [Cu/Fe] trend towards lower [Fe/H] < -1.7. We show that this may reflect the interplay between external enrichment of Cu-rich material of the Milky Way halo at low metallicities, and metallicity-dependent Cu yields from rapidly rotating massive stars. This highlights the unique diagnostic potential of accurate Cu abundances for understanding both stellar and Galactic evolution
From light emission to solar power : Experiment on LED's photovoltaic behavior
No full textAn experimental study to investigate the fundamental similarities between light-emitting diodes (LEDs) and solar cells (SCs) for educational purposes is here presented. Through a hands-on experiment using inexpensive, commercially available LEDs and simple laboratory equipment, students are introduced to characterization techniques, such as electroluminescence (EL) and current-voltage (I-V) measurements, as well as to optoelectronic devices, photovoltaic physics, spectroscopy, light-to-matter interactions, and solid-state physics concepts. Four LEDs of different colors-red, amber, green, and blue-are used in this study. The measured EL spectra allowed an estimation of the bandgap energy of the material constituting each LED's optical active layer, establishing a relationship with the LED color. Photovoltaic mode I-V curves are measured under outdoor sunlight, demonstrating that all LEDs exhibited photovoltaic behavior, generating electrical energy from incident light. The red LED produces sufficient electrical energy to power a small calculator, while the green LED exhibited the poorest photovoltaic performance. Shockley-Queisser (SQ) theory is employed to comparatively investigate the "photovoltaic" quantum efficiency (QE) of the LEDs, enabling students to relate the results to the well-known green gap problem in LED "emission" QE. This work effectively illustrates the similarities between LEDs and SCs, bridging the gap between theoretical knowledge and practical application, providing students with a valuable learning experience in solid-state physics, semiconductor-related topics, and photovoltaic technology
Evolution of a bipolar sexual compatibility system in Marasmius
No full textSexual compatibility in the Basidiomycota is governed by genetic identity at one or two loci, resulting in compatibility systems called bipolar and tetrapolar. The loci are known as HD and P/R, encoding homeodomain transcription factors and pheromone precursors and receptors, respectively. Bipolarity is known to evolve either by linkage of the two loci or by loss of mating-type determination of either the HD or the P/R locus. The ancestor to basidiomycete fungi is thought to have been tetrapolar, and many transitions to bipolarity have been described in different lineages. In the diverse genus Marasmius (Agaricales), both compatibility systems are found, and the system has been shown to follow the infrageneric sections of the genus, suggesting a single origin of bipolarity. Here, we tested this hypothesis using a comprehensive phylogenetic framework and investigated the mode by which bipolarity has evolved in this group. We utilized available genomic data and marker sequences to investigate evolution of sexual compatibility in Marasmius and allied genera. By generating a concatenated multilocus phylogeny, we found support for a single transition to known bipolarity within Marasmius. Furthermore, utilizing genomic data of the bipolar species Marasmius oreades, we found that the HD and P/R loci likely have remained unlinked through this transition. By comparing nucleotide diversity at the HD and P/R loci in Ma. oreades, we show that the HD locus has retained high diversity, and thus likely the function of determining sexual identity, as similarly in other bipolar mushroom-forming fungi. Finally, we describe the genomic architecture of the MAT loci of species of both sexual compatibility systems in Marasmiaceae and related families
Diversity of Tetractinellida (Porifera) from the Rosemary Bank Seamount and the Mid-Atlantic Ridge : A Taxonomic Study
No full textSponges (phylum Porifera), is a large and diverse group of invertebrates. In the deep-sea, sponges form aggregations, which have important ecological functions and are often dominated by sponges of the order Tetractinellida. Sponge taxonomy and identification are used to create species distribution and abundance maps. Two areas suggested to have great diversity of sponges are the Rosemary Bank Seamount and the Mid-Atlantic Ridge in the North East Atlantic. However, anthropogenic disturbances such as fishing by bottom trawling threaten the biodiversity of those areas, much of which is still unknown. In this study, taxonomic and molecular identifications were made on sponge samples from the Rosemary Bank Seamount and the Mid-Atlantic Ridge. Our results show a high diversity of sponges in the area, specifically from the order Tetractinellida. From 42 specimens, 17 species were identified from the Rosemary Bank Seamount, and 23 species from 30 specimens were identified from the Mid-Atlantic Ridge. All specimens from the Rosemary Bank Seamount belonged to the class Demospongiae, of which 83% were of the order Tetractinellida and eight genera of this order were identified. Similarly, 90% of the specimens from the Mid-Atlantic Ridge were identified as Demospongiae, 63% of them being Tetractinellida, of which five genera were identified. The results indicate that these areas contain a high diversity of sponges, especially of tetractinellids. This study will contribute to a more comprehensive distribution map of the two areas and the flagging of potential new species for science.
Contact radiotherapy for rectal cancer (CORRECT) : study protocol for a multicentre randomised phase II trial
No full textIntroduction Non-operative management of early-stage rectal cancer is increasingly recognised as a subject of significant clinical and research interest. Contact X-ray brachytherapy (CXB) offers an alternative to surgery in appropriately selected cases. Current clinical evidence suggests the use of CXB in combination with chemoradiotherapy (CRT). Although proven effective, no randomised evidence exists for the combination of CXB and short-course radiotherapy (SCRT). In this Swedish national randomised phase II trial, we aim to compare the combination of CXB with either CRT or SCRT in patients with early-to-intermediate rectal cancer. Methods and analysis A total of 110 eligible, operable patients with early-to-intermediate rectal cancer (cT1-cT3ab), with tumours measuring <5 cm in largest diameter, involving <50% of the rectal circumference, N0-N1 (<= 3 nodes <8 mm in diameter), located <= 10 cm from the anal verge and MX/M0, are randomised into two arms: standard arm (A) CXB with CRT and experimental arm (B) CXB with SCRT. The contact radiotherapy for rectal cancer (CORRECT) trial aims to evaluate whether the experimental treatment is non-inferior to standard treatment with respect to the primary endpoint 2-year organ preservation rate. On demonstrating non-inferiority in oncological outcomes compared with CXB+CRT, the combination of CXB+SCRT could pave the way for establishing a new standard of care for organ preservation in early-to-intermediate rectal cancer for patients who wish to avoid surgery. Ethics and dissemination CORRECT is conducted in accordance with research ethical approval (2024-02762-01) granted by the Swedish Research Ethics Committee on 4 June 2024. Informed consent will be obtained from all trial participants. The trial results will be published in international peer-reviewed journals. Trial registration number NCT06501053
Att plocka plockisar : Lärarnas perspektiv på det konkreta materialets påverkan i matematikundervisningen
No full textMachine learning models for predicting dysphonia following anterior cervical discectomy and fusion : a Swedish Registry Study
No full textBACKGROUND: Dysphonia is one of the more common complications following anterior cervical discectomy and fusion (ACDF). ACDF is the gold standard for treating degenerative cervical spine disorders, and identifying high-risk patients is therefore crucial. PURPOSE: This study aimed to evaluate different machine learning models to predict persistent dysphonia after ACDF. STUDY DESIGN: A retrospective review of the nationwide Swedish spine registry (Swespine). PATIENT SAMPLE: All adults in the Swespine registry who underwent elective ACDF between 2006 and 2020. OUTCOME MEASURES: The primary outcome was self-reported dysphonia lasting at least 1 month after surgery. Predictive performance was assessed using discrimination and calibration metrics. METHODS: Patients with missing dysphonia data at the 1-year follow-up were excluded. Data preprocessing involved one-hot encoding categorical variables, scaling continuous variables, and imputing missing values. Four machine learning models (logistic regression, random forest (RF), gradient boosting, K-nearest neighbor) were employed. The models were trained and tested using an 80:20 data split and 5-fold cross-validation, with performance metrics guiding the selection of the best model for predicting persistent dysphonia. RESULTS: In total, 2,708 were included in the study. Twelve key predictors were identified. Four machine learning models were tested, with the RF model achieving the best performance (AUC=0.794). The most significant predictors across models included preoperative NDI, EQ5Din- dex, preoperative neurology, number of operated levels, and use of a fusion cage. The RF model, chosen for its superior performance, showed high sensitivity and consistent accuracy, but a low specificity and positive predictive value. CONCLUSIONS: In this study, machine learning models were employed to identify predictors of persistent dysphonia following ACDF. Among the models tested, the RF classifier demonstrated superior performance, with an AUC value of 0.790. The RF model identified NDI, EQ5Dindex, and number of fused vertebrae as key variables. These findings underscore the potential of machine learning models in identifying patients at increased risk for dysphonia persisting for more than 1 month after surgery. (c) 2024 The Author(s). Published by Elsevier Inc. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/
The hematopoietic tissue of the freshwater crayfish, Pacifastacus leniusculus : organization and expression analysis
No full textThe hematopoietic tissue (HPT) and anterior proliferation center (APC) are the main hemocyte-producing organs of the freshwater crayfish, Pacifastacus leniusculus. To deepen our understanding of immune responses to various pathogens, it is essential to identify distinct hemocyte subpopulations with specific functions and to further explore how these cells are generated. Here we provide an in-depth histological study of the HPT and APC in order to localize cell types in different developmental stages, and to provide some information regarding the hemocyte differentiation in the crayfish. We localized mRNA expression of previously identified genes in the HPT/APC and hemocytes by RNA-FISH. The expression of hemolectin and transglutaminase 1 was shown to be co-localized in a high number of the HPT cells, while transglutaminase 2 was expressed in different cell types mainly associated with epithelium or endothelium. Furthermore, by double RNA-FISH for hemolectin and a previously unidentified PDGF-like factor, combined with immunostaining for prophenoloxidase, we could identify several different subtypes of hemocytes, indicating that the immune function of hemocytes in crayfish is more diversified and complex than previously appreciated
Individers upplevelse av att leva med migrän samt erfarenhet av behandling och egenvård
No full textBakgrund: Migrän är en neurologisk sjukdom som kan vara kronisk eller episodisk. Sjukdomen drabbar en stor del av jordens befolkningen och har en påverkan på individers liv. Sjukdomen kännetecknas av återkommande svår huvudvärk, ofta i samband med illamående, ljud- och ljuskänslighet. Befintlig behandling inkluderar både farmakologiska och icke-farmakologiska metoder samt egenvård, där vården har en viktig roll att stödja drabbade individer. Syfte: Syftet var att beskriva individers upplevelse av att leva med migrän samt erfarenhet av behandlingar och egenvård. Metod: En litteraturöversikt med deskriptiv ansats där 12 kvalitativa studier analyserades. Artiklarna hämtades från databaserna PubMed och CINAHL och har kvalitetsgranskats enligt SBU:s granskningsmall. Resultatanalys gjordes efter modellen av Popenoes (2021). Resultat: Studien identifierade fyra huvudkategorier: påverkan på det sociala livet, påverkan på det psykiska måendet, förebyggande behandlingar och egenvårdsstrategier. Migrän begränsar individens vardag, sociala relationer och arbetsliv. Farmakologiska och icke-farmakologiska behandlingar som botulinumtoxin och akupunktur upplevdes lindra symtomen, och egenvård i form av livsstilsförändringar var en viktig strategi för att hantera sjukdomen. Slutsats: Migrän påverkar individers liv på flera nivåer, särskilt psykiskt och socialt. Egenvård och förebyggande behandlingar har stor betydelse men det finns fortfarande behov av ökad kunskap och individanpassad vård. Sjuksköterskan kan stödja patienter genom att identifiera effektiva egenvårdsstrategier och erbjuda personcentrerad vård. Background: Migraine is a neurological disorder affecting a large portion of the global population, significantly impacting individuals' daily lives. The condition is characterized by recurrent episodes of severe headaches often accompanied by nausea, sound sensitivity and light sensitivity. Treatment includes both pharmacological and non-pharmacological methods, as well as self-care strategies where healthcare plays a crucial role in supporting affected individuals. Aim: The aim of this study was to describe individuals' experience of living with migraines and their experiences with treatment and self-care. Method: A literature review with descriptive approach, 12 qualitative studies were conducted and analyzed. The articles were retrieved from PubMed and CINAHL databases and quality-assessed using SBU's evaluation criteria. The results analysis was performed according to the model of Popenoes (2021). Results: The study identified four main categories: impact on social life, impact on mental health, preventative treatments and self-care strategies. Migraines limit individuals´ daily activities, social relationships and work life. Pharmacological and non-pharmacological treatments, such as botulinum toxin and acupuncture were perceived to relieve symptoms and self-care through lifestyle changes was an important strategy for managing the condition. Conclusion: Migraines affect individuals on multiple levels, particularly mentally and socially. Self-care and preventative treatments are crucial, but there is a need for increased knowledge and personalized care. Nurses can support patients by identifying effective self-care strategies and providing person-centred care.
Modern Soil Bench or Concrete Slab : a Natural Scientific Evaluation of Solutions that Improve a Natural Stone Foundation
No full textUppsatsen är en utvärdering av betongplattan och den moderna mullbänken som lösningar i anpassningen aven grund av natursten till en samtida boendestandard. Syftet är att genom historia, expertis och intervjuerklarlägga vad lösningarna innebär för ägaren, byggnaden, miljön och klimatet. Metoden är en kvalitativ analysav insamlat material. När bostadshuset restes på en naturstensgrund rådde en helt annan syn på konstruktionoch användning. I den samtida bostaden har kraven på energieffektivitet och komfort höjts betydligt. Med isoleringen blir grunden både kallare och fuktigare vilket ställer högre krav på fukthantering. Betongplattan är idag den mest använda lösningen i en äldre husgrund. I en befintlig grund kan dock konstruktionen inte förverkligas fullt ut. Vid mitten av 1800-talet stod de flesta husen i Sverige på en invändig mullbänk. Den moderna mullbänken är en ekologisk lösning där hela utrymmet i grunden fylls med skumglasgrus. Betongplattan är ett förmånligare alternativ som passar samman med en samtida renovering medan den moderna mullbänken ger ett mindre avtryck på klimatet och miljön samt möjliggör en varsam fortsatt renovering. Cellplast är en effektiv isolering där egenskaperna försämras över tid medan skumglaset är beständigt. Hos båda lösningarna minskar risken för fuktproblem avsevärt om byggnaden står torrt. The thesis is an evaluation of a concrete slab and a modern soil bench as solutions in adapting a natural stone foundation to a contemporary standard of living. Its aim is to clarify through history, expertise and interviews what the solutions imply to the owner, building, environment and climate. The method is a qualitative analysis of material collected from literature, expertise and interviews. When a home was built on a natural stone foundation, a completely different view of construction and use prevailed. In contemporary living the requirements for energy efficiency and comfort have increased significantly. Insulation makes the foundation both colder and more humid, which sets higher requirements on moisture management. Today concrete slab is the most used solution for housing foundations. In an existing foundation, however, the construction cannot befully realized. In the mid-1800s, most houses in Sweden stood on an interior soil bench. The modern soil bench is an ecological solution where the foundation is filled with foam glass gravel. The concrete slab is a more affordable alternative that goes well with contemporary renovation, while the modern soil bench makes a smaller impact on the climate and the environment and enables preservative renovation. Polystyrene is an effective insulator, but its properties deteriorate over time, while foam glass is a durable and long-lived material. The risk of moisture problems reduces significantly in both solutions when the building stands on dry ground. English version of results and discussion in appendix 2 at the back of the paper