Латинська Америка в дослідженнях російських етнографів за останні тридцять років

Статья посвящена истории исследований в области латиноамериканистики российскими и советскими учёными на примере научной деятельности сотрудников Института этнографии им. Н. Н. Миклухо-Маклая АН СССР (московское и ленинградское отделения).The article is dedicated to the Latin American researches provided by the Russian and Soviet scientists illustrated with the scientific activities of the representatives of the Soviet Academy of Science’s Myklukho-Maklai Ethnographical Institute (Moscow and Leningrad branches)

Uncertainty-aware multiple-instance learning for reliable classification:Application to optical coherence tomography

Deep learning classification models for medical image analysis often perform well on data from scanners that were used to acquire the training data. However, when these models are applied to data from different vendors, their performance tends to drop substantially. Artifacts that only occur within scans from specific scanners are major causes of this poor generalizability. We aimed to enhance the reliability of deep learning classification models using a novel method called Uncertainty-Based Instance eXclusion (UBIX). UBIX is an inference-time module that can be employed in multiple-instance learning (MIL) settings. MIL is a paradigm in which instances (generally crops or slices) of a bag (generally an image) contribute towards a bag-level output. Instead of assuming equal contribution of all instances to the bag-level output, UBIX detects instances corrupted due to local artifacts on-the-fly using uncertainty estimation, reducing or fully ignoring their contributions before MIL pooling. In our experiments, instances are 2D slices and bags are volumetric images, but alternative definitions are also possible. Although UBIX is generally applicable to diverse classification tasks, we focused on the staging of age-related macular degeneration in optical coherence tomography. Our models were trained on data from a single scanner and tested on external datasets from different vendors, which included vendor-specific artifacts. UBIX showed reliable behavior, with a slight decrease in performance (a decrease of the quadratic weighted kappa (κw) from 0.861 to 0.708), when applied to images from different vendors containing artifacts; while a state-of-the-art 3D neural network without UBIX suffered from a significant detriment of performance (κw from 0.852 to 0.084) on the same test set. We showed that instances with unseen artifacts can be identified with OOD detection. UBIX can reduce their contribution to the bag-level predictions, improving reliability without retraining on new data. This potentially increases the applicability of artificial intelligence models to data from other scanners than the ones for which they were developed. The source code for UBIX, including trained model weights, is publicly available through https://github.com/qurAI-amsterdam/ubix-for-reliable-classification.</p

Natuurontwikkeling in de EHS, nu zorgen voor kwaliteit!

Momenteel werken de provincies aan het nieuwe subsidiestelsel voor (agrarisch) natuurbeheer, dat het huidige Programma Beheer gaat vervangen. Het streven is het nieuwe stelsel geïmplementeerd te krijgen in 2009. Met het stelsel is veel bereikt, maar er zijn zeker ook kansen gemist, namelijk om de ecologische kwaliteit van de EHS te realiseren. In dit artikel wordt een voorzet gegeven voor het inbedden van het realiseren van ecologische kwaliteit in een nieuwe regelgeving. Er valt namelijk een kwaliteitsslag te behalen bij het omvormen van landbouwgrond naar natuu

Interaction of Cupidin/Homer2 with two actin cytoskeletal regulators, Cdc42 small GTPase and Drebrin, in dendritic spines

<p>Abstract</p> <p>Background</p> <p>Homer is a postsynaptic scaffold protein that links various synaptic signaling proteins, including the type I metabotropic glutamate receptor subunits 1α and 5, the inositol 1,4,5-trisphosphate receptor, Shank and Cdc42 small GTPase. Overexpression of Homer induces changes in dendritic spine morphology in cultured hippocampal neurons. However, the molecular basis underpinning Homer-mediated spine morphogenesis remains unclear. In this study, we aimed to elucidate the structural and functional properties of the interaction between Cupidin/Homer2 and two actin-cytoskeletal regulators, Cdc42 small GTPase and Drebrin.</p> <p>Results</p> <p>Cupidin/Homer2 interacted with activated Cdc42 small GTPase via the Cdc42-binding domain that resides around amino acid residues 191–283, within the C-terminal coiled-coil domain. We generated a Cupidin deletion mutant lacking amino acids 191–230 (CPDΔ191–230), which showed decrease Cdc42-binding ability but maintained self-multimerization ability. Cupidin suppressed Cdc42-induced filopodia-like protrusion formation in HeLa cells, whereas CPDΔ191–230 failed to do so. In cultured hippocampal neurons, Cupidin was targeted to dendritic spines, whereas CPDΔ191–230 was distributed in dendritic shafts as well as spines. Overexpression of CPDΔ191–230 decreased the number of synapses and reduced the amplitudes of miniature excitatory postsynaptic currents in hippocampal neurons. Cupidin interacted with a dendritic spine F-actin-binding protein, Drebrin, which possesses two Homer ligand motifs, via the N-terminal EVH-1 domain. CPDΔ191–230 overexpression decreased Drebrin clustering in the dendritic spines of hippocampal neurons.</p> <p>Conclusion</p> <p>These results indicate that Cupidin/Homer2 interacts with the dendritic spine actin regulators Cdc42 and Drebrin via its C-terminal and N-terminal domains, respectively, and that it may be involved in spine morphology and synaptic properties.</p

Exposure to challenging behaviours and burnout symptoms among care staff:the role of psychological resources

Background Staff supporting individuals with intellectual disabilities are at risk of burnout symptoms. Evidence suggests an association between exposure to challenging behaviours of individuals with intellectual disabilities and burnout symptoms of staff, but the protective role of staff psychological resources in this relation has been understudied. Method We investigated the association between exposure to challenging behaviours and burnout symptoms of staff and the direct and moderating effects of several psychological resources. Staff (N = 1271) completed an online survey concerning burnout symptoms (subscale Emotional Exhaustion of the Maslach Burnout Inventory), exposure to challenging behaviours and a range of potential psychological resources. We examined main and moderating effects with multilevel analyses. In order to control for the multiple comparisons, P values corrected for false discovery rate (P-FDR) were reported. Results We found a direct relation between exposure to challenging behaviours and increased levels of burnout symptoms in staff (b = .15, t(670) = 4.466, P-FDR <.0001). Perceived supervisor social support (b = -.97, t(627) = -7.562, P-FDR <.0001), staff self-efficacy (b = -.23, t(673) = -3.583, P-FDR <.0001), resilience (b = -.19, t(668) = -2.086, P-FDR <.05) and extraversion (b = -.20, t(674) = -3.514, P-FDR <.05) were associated with reduced burnout symptoms. None of the proposed psychological resources moderated the association between exposure to challenging behaviours and burnout symptoms of staff. Conclusions Of the psychological resources found to be associated with reduced risk of burnout symptoms, staff self-efficacy and access of staff to supervisor social support seem to be the factors that can be influenced best. These factors thus may be of importance in reducing the risk of developing burnout symptoms and improving staff well-being, even though the current study was not designed to demonstrate causal relations between psychological resources and burnout symptoms

Clinical characterization of 66 patients with congenital retinal disease due to the deep-intronic c.2991+1655A>G mutation in CEP290

Purpose: To describe the phenotypic spectrum of retinal disease caused by the c.2991+1655A>G mutation in CEP290 and to compare disease severity between homozygous and compound heterozygous patients. Methods: Medical records were reviewed for best-corrected visual acuity (BCVA), age of onset, fundoscopy descriptions. Foveal outer nuclear layer (ONL) and ellipsoid zone (EZ) presence was assessed using spectral-domain optical coherence tomography (SD-OCT). Differences between compound heterozygous and homozygous patients were analyzed based on visual performance and visual development. Results: A total of 66 patients were included. The majority of patients had either light perception or no light perception. In the remaining group of 14 patients, median BCVA was 20/195 Snellen (0.99 LogMAR; range 0.12-1.90) for the right eye, and 20/148 Snellen (0.87 LogMAR; range 0.22-1.90) for the left. Homozygous patients tended to be more likely to develop light perception compared to more severely affected compound heterozygous patients (P = 0.080) and are more likely to improve from no light perception to light perception (P = 0.022) before the age of 6 years. OCT data were available in 12 patients, 11 of whom had retained foveal ONL and EZ integrity up to 48 years (median 23 years) of age. Conclusions: Homozygous patients seem less severely affected compared to their compound-heterozygous peers. Improvement of visual function may occur in the early years of life, suggesting a time window for therapeutic intervention up to the approximate age of 17 years. This period may be extended by an intact foveal ONL and EZ on OCT

Book Review of Serendipity: An Ecologist’s Quest to Understand Nature

A common thought among graduate students is: “how do established scientists get where they are today?” In Serendipity: An Ecologist’s Quest to Understand Nature, James Estes offers a personal reflection on research experiences spanning his 50-year career, beginning as a Ph.D. student in 1970 and concluding with recognition as a member of the National Academy of Sciences in 2014. Estes chronologically outlines the foundational trophic cascade ecology research that he and colleagues conducted in the Aleutian Islands, examining key relationships among kelp forests, sea otters, sea urchins, and killer whales through anecdotal stories of achievement and challenge. Estes’ 3 main goals in writing this book are to: (1) recount what he had learned from 50 years of research; (2) provide a larger story of how predators and prey interact with one another; and (3) explain how science “really happens.