Publikationer från Uppsala Universitet
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Possessives as source of definite articles? : Diachronic evidence from Persian
No full textThis article discusses a distinct function of the third person singular pronominal clitic =eš in Persian: to denote definiteness. In certain possessive constructions, =eš does not refer to an external possessor but serves to make its host identifiable – whether through association with another item in the linguistic or situational context or as an anaphoric definite marker without any association. The use of possessive markers for definiteness has been observed in Uralic, Trans-Eurasian, Austronesian, Semitic, and Mayan language families; this study presents evidence of a similar development in Persian, an Indo-European language of the southwestern Iranian branch. The present article examines various definite uses of =eš through colloquial examples from social media and historical examples from a New Persian corpus. The findings trace the development of =eš, illustrating how its associative link to external entities weakens over time until it functions as an anaphoric definite marker. A tentative grammaticalization path is proposed in which the abstraction of the possessive meanings leads to the eventual loss of possessive semantics in =eš, resulting in the loss of person and number features in anaphoric uses. Additionally, the article discusses how increasing frequency of =eš has contributed to its development across stages of New Persian
Organic Peroxides in Transition-Metal-Free Cyclization and Coupling Reactions (C-C) via Oxidative Transformation
No full textTransition-metal-free transformations are recognized as green and sustainable methods for constructing carbon-carbon bonds in organic synthesis. This review describes the application of six organic peroxides, including tert-butyl hydroperoxide (TBHP), di-tert-butyl peroxide (DTBP), tert-butyl peroxybenzoate (TBPB), benzoyl peroxide (BPO), dialauroyl peroxide (DLP), and diguyl peroxide (DCP), in C-C bond construction, highlighting selected examples and mechanisms of challenging transformations. Each section concludes with a detailed overview of suitable reagents for various coupling reactions and strengths and weaknesses of the reported works. This work aims to inspire further innovations in transition-metal-free oxidative transformations, promoting sustainable and eco-friendly chemical processes and paving the way for new peroxide-based organic synthesis methods
Faktorer som främjar elevers motivation i matematikklassrummet
No full textDenna studie undersöker hur klassrumsmiljö samt inre och yttre motivationsfaktorer påverkar elevers lärande i matematik. Studien anknyter till tidigare forskningar, däribland Saeed & Zyngier (2012), som med stöd i Self-determination theory belyser hur inre och yttre motivation påverkar elevers lärande och engagemang. Studien tar sin teoretiska utgångspunkt i två psykologiska teorier: Self-determination theory och Operant betingning med rötter i behaviorismen. Syftet är att belysa hur klassrumsmiljö samt inre och yttre motivationsfaktorer samspelar i klassrummet och påverkar elevernas prestationer. Frågeställningarna som studien undersöker är “Vilken betydelse har klassrumsmiljön för att främja elevers motivation?” och “Hur påverkar elevernas inre- och yttre motivation deras skolarbete?”. Studien bygger på kvalitativa intervjuer med totalt tio elever från två olika skolor. Deltagarnas svar jämfördes för att identifiera likheter och skillnader i hur klassrumsmiljön och motivationsfaktorer påverkar elevers motivation och lärande. En tematisk analys identifierade fem teman; placeringar, belöning, bestraffning, valmöjlighet samt positiv feedback. Resultaten visar att placeringar i klassrummet har stor påverkan på elevers samarbete, koncentration, trygghet och lärande. Valmöjligheter och positiv feedback stärker elevers motivation och lärande. Eleverna känner sig mer engagerade när de har kontroll över sitt lärande och får positiv respons för sina prestationer. Yttre motivation att belöningar stärker elevers motivation och prestation, medan bestraffningar kan ha motsatt effekt.
Specific host factors determine resistance in a North American crayfish to the crayfish plague, Aphanomyces astaci
No full textThe crayfish plague is caused by the oomycete Aphanomyces astaci with North American crayfish (for example Pacifastacus leniusculus and Procambarus clarkii) serving as carriers and vectors for this pathogen. This poses a constant threat to native crayfish in Europe, Asia, South America and Australia, which all are highly susceptible to this pathogen. In this study we now show how the symbiotic balance between the pathogen and its host are maintained at the molecular level. The host factors involved in this balance between the pathogen, A. astaci and the host, P. leniusculus, are one glycine-rich antimicrobial peptide (GRP) that is specifically active against A. astaci, but not to other microorganisms and two Kazal proteinase inhibitors (KPI2 and KPILA) inhibit secreted A. astaci proteases by binding to subtilisin enzymes from the pathogen. Accordingly, the expression of GRP, KPI2, KPILA, as well as proPO mRNAs increases following A. astaci infection. Silencing GRP, or KPI2 + KPILA mRNAs results in death of the crayfish from infection. Over time, this host-pathogen relationship has evolved to allow resistant crayfish to coexist with A. astaci in their cuticle for life, provided critical components remain unaltered by environmental changes or other pathogens. It is unclear whether a similar relationship could develop between currently susceptible crayfish and A. astaci
Unveiling chemomechanical degradation in aqueous batteries with online acoustic emission sensing
No full textOnline acoustic emission (AE) sensing is a promising nondestructive technique for battery health monitoring. Herein, we report on the ability of AE sensing to differentiate among different chemomechanical degradation events in a TiS2-based model aqueous chemistry. Short and high-frequency AE signals primarily stem from fracture-related degradation of TiS2, such as layer delamination, exfoliation, and cracking. Long and lowfrequency signals originate from gas bubbles bursting when the cell is cycled outside the water stability window. The two processes demonstrate distinct AE features, allowing them to be semi-quantitatively distinguished from both time and frequency domains. Complementary physicochemical characterizations have been conducted to correlate with the AE observation, including online electrochemical mass spectrometry, operando synchrotron X-ray diffraction, and ex situ scanning electron microscopy. Our work indicates that online AE sensing holds the promise to identify complex chemomechanical degradation processes in batteries with liquid and potentially solid electrolytes
Characterization and Targeting of Glioblastoma Peritumoral Cells
No full text Glioblastoma (GB) is a highly aggressive and resistant brain tumor with a dismal prognosis due to its extreme heterogeneity. Recurrences often occur near the resection cavity, suggesting their origin from the peritumoral cells. Here, we utilize GB’s invasion and migration capacity to lure and trap glioblastoma cells in the hydrogel, especially the infiltrative peritumoral cells, potentially offering a novel therapeutic approach. The study first identified prospective chemoattractants and potential cell cultures used for the development of CD44-targeting nanoparticles by analyzing the RNA microarray of GB cell cultures. Then, the migration ability of matched GB cell cultures derived from bulk and edge tissue towards four chemokines CXCL12, CCLL11, CXCL10, and OSM in a two-dimensional manner with transwell migration assay was investigated and was found to be specifically responsive to CXCL12 and CCL11. Then, the effect of these chemokines on the proliferation and functional properties of the cell cultures was tested with immunostaining, clonogenic assay, and collagen invasion assay. Next, we evaluated the glioblastoma cells’ migration through three-dimensional space with CXCL12-encapsulated hydrogel. Lastly, the safety of hyaluronan-based hydrogel was confirmed with mouse brain slice cultures, underscoring its potential to be used as a therapeutic method. Overall, this thesis illustrates the importance of studying cell migration and invasive behavior of GB, particularly peritumoral cells, and exploits this behavior to develop a hyaluronan-based hydrogel to attract and trap these infiltrative cells. By identifying key chemoattractants such as CXCL12 and CCL11 and validating their effects on cell migration and function as well as proof-of-concept of hydrogels in attracting GB cells, this research establishes a foundation for localized therapy.
What factors are associated with surgical site infections after intracranial neurosurgical procedures? : An exploratory register study
No full textBackground: Surgical site infections (SSIs) after intracranial neurosurgical procedures derive from both endogenous and exogenous factors, and are associated with increased morbidity, mortality and additional socio-economic costs. The addition of mobile laminar airflow (MLAF) units to the operating room ventilation decreases bacteria-carrying particles, but their influence on the incidence of SSIs, and concurrence with other factors, is unclear. This is a continuation study of a previous study using MLAF units. Aim: To explore factors associated with SSIs after intracranial procedures during a period when MLAF units were used. Methods: This retrospective register study had an explorative design. The electronic medical records of patients undergoing intracranial neurosurgical procedures were reviewed retrospectively for signs or symptoms of SSIs using a 45-item protocol. Demographic, patient-specific and procedure-specific variables were collected, as well as exogenous factors and SSI variables regarding depth of SSI, type of bacteria, time to infection, and treatment. Data were analysed using univariate and multi-variate logistic regression. Findings: An SSI occurred in 55 of 800 included patients (6.9%). On univariate and multivariate analysis, only remote infections during the hospital stay were associated with risk of SSI (odds ratio 2.02, 95% confidence interval 1.07-3.82; P1/40.031). Superficial SSIs were most common, the median time to infection was 18 days, and the most common causative micro-organism was Staphylococcus aureus. Conclusions: In the clinical context, considerations are recommended for neurosurgical patients with ongoing remote infections during their hospital stay. Further peri-operative studies are needed in the field of surgical infection prevention
Psychometric properties and diagnostic accuracy of the DUDIT and ASSIST-Y for cannabis use in adolescents in Sweden
No full textAimsAdolescent substance use presents significant public health concerns, leading to risk of developing substance use disorders later in life. Early identification through reliable screening tools is essential. This study evaluated the psychometric properties and diagnostic screening accuracy, for identifying cannabis use, of two widely used tools: the DUDIT and the ASSIST-Y cannabis use subscale, in a Swedish adolescent population.MethodsData were collected from 1450 randomly selected adolescents and a sample of 60 treatment-seeking adolescents, all 15 to 18 years old. Internal consistency was measured using Cronbach's alpha, and test-retest reliability assessed with intraclass correlation coefficients (ICC). Construct validity was investigated through exploratory factor analysis, and diagnostic screening accuracy determined via receiver operating characteristic (ROC) analysis.ResultThe DUDIT and ASSIST-Y demonstrated good (alpha = 0.89) and moderate (alpha = 0.55) internal consistency, respectively. Test-retest reliability was good for the DUDIT (ICC = 0.88) and moderate for the ASSIST-Y (ICC = 0.68). Factor analysis indicated an ambiguous structure for both instruments, where the two instruments measure different aspects of substance use-related problems. Both instruments showed moderate to good diagnostic screening accuracy. The optimal cut-off scores for boys and girls on the DUDIT are 4 and 1, respectively, and for the ASSIST-Y, 3 for boys and 2/3 for girls.ConclusionsBoth scales demonstrated ambiguous construct validity and results suggest that the ASSIST-Y cannabis use subscale requires refinement, particularly concerning its internal reliability. In sum, the DUDIT performed better than the ASSIST-Y, indicating that the DUDIT is a reliable screening tool for substance use among an adolescent general population
Reconciling democracy and sustainability : three political challenges and the role of democratic innovations
No full textGoverning sustainability challenges such as climate change or biodiversity loss presents a profound democratic dilemma. Although democratic practices and procedures are widely regarded as essential for collectively addressing complex sustainability issues, liberal democracies have been criticized by some scholars for their inability to effectively tackle global environmental threats like climate change. We reconcile these positions by outlining how the emerging field of democratic innovations can help to address the critical challenges that democracies face when governing sustainability transformations. We focus on three issues liberal democracies are confronted with: reformist incrementalism, (de)politicization, and imaginary boundaries. We then exemplify how democratic innovations such as deliberative mini-publics, participatory budgeting, and material participation can help address these challenges. Our review suggests that democratic innovations hold the potential to address political concerns, find compromises between extreme positions, reconnect people's everyday lives with the grand sustainability challenges they face, and allow for alternative visions of a desirable future society. However, we also address cautionary tales, discuss the limitations of democratic innovations, and outline avenues for future research, which we believe can help further elaborate and develop participatory approaches to critical sustainability challenges
Optimized Artificial Colonic Mucus Enabling Physiologically Relevant Diffusion Studies of Drugs, Particles, and Delivery Systems
No full textDevelopment of oral drug delivery systems that penetrate the colonic mucus remains challenging. Artificial models of porcine colonic mucus have been developed that mimic the rheology and viscosity of the native mucus and its contents of mucins, protein, and lipids. However, they are less representative with regard to the zeta potential, a factor of importance for charged molecules and particles. This study therefore aimed to improve the existing porcine artificial colonic mucus model by exchanging the polymer backbone (used for viscosity) to more closely mimic the charge of porcine native colonic mucus. Polymers studied were poly(acrylic acid), hydroxyethylcellulose, sodium hyaluronate, sodium alginate, and pectin. The resulting porcine artificial colonic mucus was assayed for apparent viscosity, storage modulus, pH, water content, zeta potential, and pore size. The two best-performing polymers (poly(acrylic acid) and hydroxyethylcellulose) were then assayed with diffusion of FITC-dextran, particle tracking of nanoparticles, and binding of FITC-dextran and contrasted to data generated in porcine native colonic mucus (PNCM). Of the two polymers, PACM based on HEC generated zeta potential and binding kinetics similar to those of PNCM. We conclude that the choice of polymer in PACMs is critical for improving their use in drug development. The extensive characterization of the PACMs further points toward the importance of complementary techniques to determine rheological characteristics, mesh, and pore size