Modeling human color categorization: color discrimination and color memory

Color matching in Content-Based Image Retrieval is done using a color space and measuring distances between colors. Such an approach yields non-intuitive results for the user. We introduce color categories (or focal colors), determine that they are valid, and use them in two experiments. The experiments conducted prove the difference between color categorization by the cognitive processes color discrimination and color memory. In addition, they yield a Color Look-Up Table, which can improve color matching, that can be seen as a model for human color matching

Implementation of clinical guidelines on physical therapy for patients with low back pain: randomized trial comparing patient outcomes after a standard and active implementation strategy

Contains fulltext : 47628.pdf (publisher's version ) (Closed access)BACKGROUND AND PURPOSE: An active strategy was developed for the implementation of the clinical guidelines on physical therapy for patients with low back pain. The effect of this strategy on patients' physical functioning, coping strategy, and beliefs regarding their low back pain was studied. SUBJECTS: One hundred thirteen primary care physical therapists treated a total of 500 patients. METHODS: The physical therapists were randomly assigned to 1 of 2 groups. The control group received the guidelines by mail (standard passive method of dissemination). The intervention group, in contrast, received an additional active training strategy consisting of 2 sessions with education, group discussion, role playing, feedback, and reminders. Patients with low back pain, treated by the participating therapists, completed questionnaires on physical functioning, pain, sick leave, coping, and beliefs. RESULTS: Physical functioning and pain in the 2 groups improved substantially in the first 12 weeks. Multilevel longitudinal analysis showed no differences between the 2 groups on any outcome measure during follow-up. DISCUSSION AND CONCLUSION: The authors found no additional benefit to applying an active strategy to implement the physical therapy guidelines for patients with low back pain. Active implementation strategies are not recommended if patient outcomes are to be improved

Эффективность комбинированных криоконсервантов, содержащих глицерин или 1,2-пропандиол, при замораживании эритроцитов

Исследовали осмотические свойства эритроцитов, замороженных в комбинированных криоконсервантах, содержащих полимерные непроникающие (декстран, полиэтиленгликоль) и проникающие (глицерин, 1,2-пропандиол) криопротекторы. Установлено, что в эритроцитах, замороженных-отогретых в среде с полимерами, отмечается повышение скорости потока ионов Н+ и осмотической хрупкости в среде, содержащей 0,45–0,9% NaCl. Для сохранения осмотических свойств замороженных- отогретых клеток достаточно включить в среду глицерин или 1,2-пропандиол (1,2-ПД) в концентрации 5%. Полученные результаты позволяют предположить, что криопротекторная эффективность комбинированных криоконсервантов, содержащих непроникающие и проникающие криопротекторы, определяется вкладом различных по механизму действия криозащитных компонентов в суммарную защитную эффективность при замораживании и ослаблением постгипертонического стресса на клетки при размораживании.Досліджували осмотичні властивості еритроцитів, заморожених-відігрітих у комбінованих кріоконсервантах, які містять полімерні непроникаючі (декстран, поліетиленгліколь) і проникаючі (гліцерин, 1,2-пропандіол) кріопротектори. Встановлено, що в еритроцитах, заморожених-відігрітих у середовищі з полімерами, визначається зростання швидкості потоку іонів Н+ і осмотичної крихкості в середовищі, яке містить 0,45–0,9% NaCl. Для збереження осмотичних властивостей заморожених- відігрітих клітин достатньо включити в середовище гліцерин або 1,2-пропандіол в концентрації 5%. Отримані результати дозволяють припустити, що кріопротекторна ефективність комбінованих кріоконсервантів, які містять непроникаючі і проникаючі кріопротектори, визначається внеском різноманітних за механізмом дії кріозахисних компонентів у сумарну захисну ефективність при заморожуванні та послабленням постгіпертонічного стресу на клітини при розморожуванні.The osmotic properties of erythrocytes frozen-thawed in combined cryopreservatives, containing polymeric non-penetrating (dextran, polyethylene glycol) and penetrating (glycerol, 1,2-propane diol) cryoprotectants were studied. It was established that in erythrocytes frozen-thawed in the presence of polymers the increasing of H+ ion flow rate and osmotic fragility in the environment with 0.45–0.9% NaCl was observed. It is sufficient to add 5% glycerol or 1,2-propane diol (1,2-PD) to the medium to preserve osmotic properties of frozen-thawed cells. The obtained results enable to suggest that cryoprotective efficiency of combined cryopreservatives, containing non-penetrating and penetrating cryoprotectants is determined both by the contribution of cryoprotective components differing by action mechanism into th

Flavonoids Influence Monocytic GTPase Activity and Are Protective in Experimental Allergic Encephalitis

In the chronic disabling disease multiple sclerosis (MS), migration of monocytes across the blood-brain barrier is a crucial step in the formation of new lesions in the central nervous system (CNS). Infiltrating monocyte-derived macrophages secrete inflammatory mediators such as oxygen radicals, which contribute to axonal demyelination and damage, resulting in neurological deficits. Flavonoids are compounds occurring naturally in food, which scavenge oxygen radicals and have antiinflammatory properties. To investigate whether they might suppress clinical symptoms in MS, we treated rats sensitized for acute and chronic experimental allergic encephalomyelitis, an experimental model of MS, with flavonoids. We demonstrated that the flavonoid luteolin substantially suppressed clinical symptoms and prevented relapse when administered either before or after disease onset. Luteolin treatment resulted in reduced inflammation and axonal damage in the CNS by preventing monocyte migration across the brain endothelium. Luteolin influenced migration by modulating the activity of Rho GTPases, signal transducers involved in transendothelial migration. Oral administration of luteolin also significantly reduced clinical symptoms

Stratification of COPD patients towards personalized medicine:reproduction and formation of clusters

BACKGROUND: The global initiative for chronic obstructive lung disease (GOLD) 2020 emphasizes that there is only a weak correlation between FEV(1), symptoms and impairment of the health status of patients with chronic obstructive pulmonary disease (COPD). Various studies aimed to identify COPD phenotypes by cluster analyses, but behavioral aspects besides smoking were rarely included. METHODS: The aims of the study were to investigate whether (i) clustering analyses are in line with the classification into GOLD ABCD groups; (ii) clustering according to Burgel et al. (Eur Respir J. 36(3):531–9, 2010) can be reproduced in a real-world COPD cohort; and (iii) addition of new behavioral variables alters the clustering outcome. Principal component and hierarchical cluster analyses were applied to real-world clinical data of COPD patients newly referred to secondary care (n = 155). We investigated if the obtained clusters paralleled GOLD ABCD subgroups and determined the impact of adding several variables, including quality of life (QOL), fatigue, satisfaction relationship, air trapping, steps per day and activities of daily living, on clustering. RESULTS: Using the appropriate corresponding variables, we identified clusters that largely reflected the GOLD ABCD groups, but we could not reproduce Burgel’s clinical phenotypes. Adding six new variables resulted in the formation of four new clusters that mainly differed from each other in the following parameters: number of steps per day, activities of daily living and QOL. CONCLUSIONS: We could not reproduce previously identified clinical COPD phenotypes in an independent population of COPD patients. Our findings therefore indicate that COPD phenotypes based on cluster analysis may not be a suitable basis for treatment strategies for individual patients. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1186/s12931-022-02256-7

Effectiviteit van een actieve implementatiestrategie van de KNGF-richtlijn 'lage-rugpijn'

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Development of refractive errors - what can we learn from inherited retinal dystrophies?

PURPOSE: It is unknown which retinal cells are involved in the retina-to-sclera signaling cascade causing myopia. As inherited retinal dystrophies (IRD) are characterized by dysfunction of a single retinal cell type and have a high risk of refractive errors, a study investigating the affected cell type, causal gene and refractive error in IRDs may provide insight herein. DESIGN: Case-control study. METHODS: _Study population:_ 302 patients with IRD from two ophthalmogenetic centers in the Netherlands. _Reference population:_ population-based Rotterdam Study-III and ERF Study (N=5,550). Distributions and mean spherical equivalent (SE) were calculated for main affected cell type and causal gene; and risks of myopia and hyperopia were evaluated using logistic regression. RESULTS: Bipolar cell related dystrophies were associated with the highest risk of SE high myopia 239.7; OR mild hyperopia 263.2, both P<0.0001; SE -6.86 D [SD 6.38]); followed by cone dominated dystrophies (OR high myopia 19.5, P<0.0001; OR high hyperopia 10.7, P=0.033; SE -3.10 D [SD 4.49]); rod dominated dystrophies (OR high myopia 10.1, P<0.0001; OR high hyperopia 9.7, P=0.001; SE -2.27 D [SD 4.65]); and RPE related dystrophies (OR low myopia 2.7; P=0.001; OR high hyperopia 5.8; P=0.025; SE -0.10 D [SD 3.09]). Mutations in RPGR (SE -7.63 D [SD 3.31]) and CACNA1F (SE -5.33 D [SD 3.10]) coincided with the highest degree of myopia; in CABP4 (SE 4.81 D [SD 0.35]) with the highest degree of hyperopia. CONCLUSIONS: Refractive errors, in particular myopia, are common in IRD. The bipolar synapse, and the inner and outer segments of the photoreceptor may serve as critical sites for myopia development

Modelling of particulate matter concentrations and source contributions in the Helsinki Metropolitan Area in 2008 and 2010

We refined an urban-scale dispersion modelling system by adding a road dust suspension model, FORE. The deterministic modelling includes both vehicular exhaust emissions (including cold start and cold driving) and suspended road dust. The urban scale modelling system was used in combination with the regional scale chemical transport model LOTOSEUROS, for 2008, and the measured regional background concentrations, for 2010. The predictions were compared against measured concentrations of PM2.5 and PM10. PM2.5 concentrations were slightly and the PM10concentrations substantially under-predicted in 2008, mainly due to the under-predicted regional background concentration. Source contributions of suspended road dust varied from 2% to 8% and from 12% to 38% for PM2.5 and PM10, respectively. Long-range transported contributions at the urban traffic stations were 72% to 92% for PM2.5 and 50% to 83% for PM10. © 2016

Surveillance-embedded genomic outbreak resolution of methicillin-susceptible Staphylococcus aureus in a neonatal intensive care unit

We observed an increase in methicillin-susceptible Staphylococcus aureus (MSSA) infections at a Dutch neonatal intensive care unit. Weekly neonatal MSSA carriage surveillance and cross-sectional screenings of health care workers (HCWs) were available for outbreak tracing. Traditional clustering of MSSA isolates by spa typing and Multiple-Locus Variable number tandem repeat Analysis (MLVA) suggested that nosocomial transmission had contributed to the infections. We investigated whether whole-genome sequencing (WGS) of MSSA surveillance would provide additional evidence for transmission. MSSA isolates from neonatal infections, carriage surveillance, and HCWs were subjected to WGS and bioinformatic analysis for identification and localization of high-quality single nucleotide polymorphisms, and in-depth analysis of subsets of isolates. By measuring the genetic diversity in background surveillance, we defined transmission-level relatedness and identified isolates that had been unjustly assigned to clusters based on MLVA, while spa typing was concordant but of insufficient resolution. Detailing particular subsets of isolates provided evidence that HCWs were involved in multiple outbreaks, yet it alleviated concerns about one particular HCW. The improved resolution and accuracy of genomic outbreak analyses substantially altered the view on outbreaks, along with apposite measures. Therefore, inclusion of the circulating background population has the potential to overcome current issues in genomic outbreak inference