UTUPub
Not a member yet
55238 research outputs found
Sort by
Motivation across a transition: Changes in achievement goal orientations and academic well-being from elementary to secondary school
Full text linkThe aim of this study was to examine i) the prevalence of achievement goal orientation profiles among Finnish sixth- and seventh-graders (N = 419), ii) the stability and change in these profiles across the transition from elementary to lower secondary school, and iii) the profile differences in academic achievement (grades) and academic well-being (school engagement and school burnout). Using latent profile analysis, four goal orientation profiles were extracted: indifferent, success-oriented, mastery-oriented, and avoidance-oriented. Latent transition analysis confirmed that these profiles were stably identified over time. There was substantial stability in profiles: being assigned to the same group yielded the highest transition probabilities (0.63–0.75). Likely transitions were from success-oriented to indifferent and from indifferent to avoidance-oriented. Of those who transitioned, the majority moved from more to less favorable profiles. Students who stayed in the mastery-oriented group across the transition displayed the most adaptive pattern of motivation, academic achievement, and well-being.</p
PARP Inhibitors in Prostate Cancer-the Preclinical Rationale and Current Clinical Development
Full text linkProstate cancer is globally the second most commonly diagnosed cancer type in men. Recent studies suggest that mutations in DNA repair genes are associated with aggressive forms of prostate cancer and castration resistance. Prostate cancer with DNA repair defects may be vulnerable to therapeutic targeting by Poly(ADP-ribose) polymerase (PARP) inhibitors. PARP enzymes modify target proteins with ADP-ribose in a process called PARylation and are in particular involved in single strand break repair. The rationale behind the clinical trials that led to the current use of PARP inhibitors to treat cancer was to target the dependence of BRCA-mutant cancer cells on the PARP-associated repair pathway due to deficiency in homologous recombination. However, recent studies have proposed therapeutic potential for PARP inhibitors in tumors with a variety of vulnerabilities generating dependence on PARP beyond the synthetic lethal targeting of BRCA1/BRCA2 mutated tumors, suggesting a wider potential than initially thought. Importantly, PARP-associated DNA repair pathways are also closely connected to androgen receptor (AR) signaling, which is a key regulator of tumor growth and a central therapeutic target in prostate cancer. In this review, we provide an extensive overview of published and ongoing trials exploring PARP inhibitors in treatment of prostate cancer and discuss the underlying biology. Several clinical trials are currently studying PARP inhibitor mono-and combination therapies in the treatment of prostate cancer. Integration of drugs targeting DNA repair pathways in prostate cancer treatment modalities allows developing of more personalized care taking also into account the genetic makeup of individual tumors
Prognostic value of a novel artificial intelligence-based coronary CTA-derived ischemia algorithm among patients with normal or abnormal myocardial perfusion
Full text linkBackground: Among patients with obstructive coronary artery disease (CAD) on coronary computed tomography angiography (CTA), downstream positron emission tomography (PET) perfusion imaging can be performed to assess the presence of myocardial ischemia. A novel artificial-intelligence-guided quantitative computed tomography ischemia algorithm (AI-QCTischemia) aims to predict ischemia directly from coronary CTA images. We aimed to study the prognostic value of AI-QCTischemia among patients with obstructive CAD on coronary CTA and normal or abnormal downstream PET perfusion.Methods: AI-QCTischemia was calculated by blinded analysts among patients from the retrospective coronary CTA cohort at Turku University Hospital, Finland, with obstructive CAD on initial visual reading (diameter stenosis ≥50%) being referred for downstream 15O-H2O-PET adenosine stress perfusion imaging. All coronary arteries with their side branches were assessed by AI-QCTischemia. Absolute stress myocardial blood flow ≤2.3 ml/g/min in ≥2 adjacent segments was considered abnormal. The primary endpoint was death, myocardial infarction, or unstable angina pectoris. The median follow-up was 6.2 [IQR 4.4-8.3] years.Results: 662 of 768 (86%) patients had conclusive AI-QCTischemia result. In patients with normal 15O-H2O-PET perfusion, an abnormal AI-QCTischemia result (n = 147/331) vs. normal AI-QCTischemia result (n = 184/331) was associated with a significantly higher crude and adjusted rates of the primary endpoint (adjusted HR 2.47, 95% CI 1.17-5.21, p = 0.018). This did not pertain to patients with abnormal 15O-H2O-PET perfusion (abnormal AI-QCTischemia result (n = 269/331) vs. normal AI-QCTischemia result (n = 62/331); adjusted HR 1.09, 95% CI 0.58-2.02, p = 0.794) (p-interaction = 0.039).Conclusion: Among patients with obstructive CAD on coronary CTA referred for downstream 15O-H2O-PET perfusion imaging, AI-QCTischemia showed incremental prognostic value among patients with preserved perfusion by 15O-H2O-PET imaging, but not among those with reduced perfusion</p
« Derrière OGM il y a modifié ! »: Étude sémantique sur la plurivocité du sigle OGM
Full text linkDans sa forme longue, OGM peut être écrit organisme génétiquement modifié ou organisme génétiquement manipulé. Cet article a pour but d’offrir une description sémantique de la notion d’OGM et d’en connaître les conceptions des locuteurs natifs du français. Pour ce faire, des francophones ont été interrogés dans le cadre d’un sondage sur la forme longue qu’ils préfèrent et les raisons de choisir cette forme. Leurs justifications sont abordées en prenant en compte des aspects sémantiques, normatifs et idéologiques afin de donner un regard détaillé sur la signification du sigle OGM. Les résultats de l’article montrent qu’une majorité des répondants du sondage ont préféré l’adjectif modifié. Plusieurs répondants ont trouvé que manipulé véhicule difficilement l’idée de changement qui leur était essentielle dans la signification d’OGM. Les réponses retenues esquissent une vision complexe de l’OGM qui pourrait servir pour des analyses ultérieures.</p
Dynamic adaptation of phytoplankton vertical migration to changing grazing and nutrient conditions
Full text linkDespite the ubiquitous occurrence of vertical migration of phytoplankton its quantitative significance remains poorly known. We eliminated a dense Daphnia population in a pond by introducing whitefish fingerlings, and assessed the effects on the vertical migration of dominating motile phytoplankton. At the highest abundance of Daphnia, cryptophytes reduced grazing losses by staying in the hypolimnion day and night, but Mallomonas species armoured by silica bristles remained in the epilimnion. After the fish introduction, phytoplankton was released from Daphnia grazing pressure, allowing cryptophytes to occur in the epilimnion also at noon. At the same time, increased phytoplankton biomass exacerbated the nutrient depletion. Cryptophytes compensated for that by migrating into the anoxic hypolimnion, whereupon their growth rates increased. The collapse of Daphnia was also associated with a temporary increase in nutrient regeneration by enzyme activities and decreases in total nutrient concentration and bacterial biomass in the whole water column. Our results show that cryptophytes can dynamically modify their vertical migration to balance between the exploitation of various nutrient resources and the risk of becoming eaten. Hypolimnetic nutrient resources can be quantitatively more important for phytoplankton than previously assumed.</p
Anthropogenic bottom-up and top-down impacts on boreal breeding waterbirds
Full text linkWetland habitats are changing under multiple anthropogenic pressures. Nutrient leakage and pollution modify physico-chemical state of wetlands and affect the ecosystem through bottom-up processes, while alien predators affect the ecosystems in a top-down manner. Boreal wetlands are important breeding areas for several waterbird species, the abundances of which potentially reflect both bottom-up and top-down ecosystem processes. Here, we use long-term national monitoring data gathered from c. 130 waterbird breeding sites in Finland from the 1980s to the 2020s. We hypothesised that the physico-chemical state of the waters and increasing alien predator abundance both play a role in steering the waterbird population trends. We set out to test this hypothesis by relating population changes of 17 waterbird species to changes in water chemistry and to regional alien predator indices while allowing species-specific effects to vary with foraging niche (dabblers, invertivore divers, piscivorous divers, herbivores), nesting site, female mass and habitat (oligotrophic, eutrophic). We found niche and nesting site-specific, habitat-dependent changes in waterbird numbers. While the associations with higher phosphorus levels and browning water were in overall positive at the oligotrophic lakes, the numbers of invertivore and piscivore diving ducks were most strongly negatively associated with higher phosphorus levels and browning water at the eutrophic lakes. Furthermore, increased pH levels benefitted piscivores. Invertivore diving duck species nesting on the wetlands had declined most on sites with high alien predator indices. Large herbivorous species and species preferring oligotrophic lakes seem to be successful. We conclude that the large-scale breeding waterbird decline in Finland is closely connected to both bottom-up and top-down processes, where negative associations are emphasised especially at eutrophic lakes. Niche-, nest site- and habitat-specific management actions are required to conserve declining waterbird populations. Managing wetlands on catchments level together with alien predator control may provide important approaches to future wetland management.</p
Brightest cluster galaxies: the centre can(not?) hold
Full text linkWe explore the persistence of the alignment of brightest cluster galaxies (BCGs) with their local environment. We find that a significant fraction of BCGs do not coincide with the centroid of the X-ray gas distribution and/or show peculiar velocities (they are not at rest with respect to the cluster mean). Despite this, we find that BCGs are generally aligned with the cluster mass distribution even when they have significant offsets from the X-ray centre and significant peculiar velocities. The large offsets are not consistent with simple theoretical models. To account for these observations BCGs must undergo mergers preferentially along their major axis, the main infall direction. Such BCGs may be oscillating within the cluster potential after having been displaced by mergers or collisions, or the dark matter halo itself may not yet be relaxed
The effect of neural network architecture on virtual H&E staining: Systematic assessment of histological feasibility
Full text linkConventional histopathology has relied on chemical staining for over a century. The staining process makes tissue sections visible to the human eye through a tedious and labor-intensive procedure that alters the tissue irreversibly, preventing repeated use of the sample. Deep learning-based virtual staining can potentially alleviate these shortcomings. Here, we used standard brightfield microscopy on unstained tissue sections and studied the impact of increased network capacity on the resulting virtually stained H&E images. Using the generative adversarial neural network model pix2pix as a baseline, we observed that replacing simple convolutions with dense convolution units increased the structural similarity score, peak signal-to-noise ratio, and nuclei reproduction accuracy. We also demonstrated highly accurate reproduction of histology, especially with increased network capacity, and demonstrated applicability to several tissues. We show that network architecture optimization can improve the image translation accuracy of virtual H&E staining, highlighting the potential of virtual staining in streamlining histopathological analysis.</p