Optimizing multiplexed imaging experimental design through tissue spatial segregation estimation

Recent advances in multiplexed imaging methods allow simultaneous detection of dozens of proteins or RNAs enabling deep spatial characterization of both healthy and tumor tissues. Parameters for design of optimal sequencing-based experiments have been established, but such parameters are lacking for multiplex imaging studies. Here, using a spatial transcriptomic atlas of healthy and tumor human tissues, we developed a new statistical framework that determines the number of fields of view necessary to accurately identify all cell types that are part of the tissue. Using this strategy on imaging mass cytometry data, we identified a measurement of tissue spatial segregation that enables optimal experimental design and that is technology invariant. This strategy will enable significantly improved design of multiplexed imaging studies.

EVALUATION OF THE PHENOMENON OF SPATIAL SEGREGATION IN LVIV. HISTORICAL ASPECT

The article attempts to outline the phenomenon of spatial segregation in Lviv. It highlights the historical aspects of this phenomenon, and their impact on the current situation. Also is outlined the own classification of the social groups which have developed at present city is considering the degree of their mutual isolation. It was found that in the historical aspect of spatial segregation in Lviv can be divided into three periods: - medieval (when it was discriminatory), Soviet (when it was a privilege marking of politically "trustworthy"), and modern (associated with property stratification). Each of these segregation stages has left its mark on the spatial character of the city, albeit to varying degrees. Thus, the medieval discriminatory segregation of space is now practically inactive; the Soviet partially changed its direction and lost its original meaning, the modern one is at the stage of active development and deepening. Eight social categories have been identified in modern Lviv, in relation to which the process of spatial segregation is taking place. Accordingly, an assessment of the phenomenon of spatial segregation is given, which should take into account the following factors: a) the frequency of intersection of social groups of different categories; b) the place where this intersection takes place (for example citywide holidays); c) territorial distribution of spatially segregated groups. Preliminarily assessed the isolation level of different social groups, which also has a urban dimension.

Fine-scale spatial segregation in a pelagic seabird driven by differential use of tidewater glacier fronts

In colonially breeding marine predators, individual movements and colonial segregation are influenced by seascape characteristics. Tidewater glacier fronts are important features of the Arctic seascape and are often described as foraging hotspots. Albeit their documented importance for wildlife, little is known about their structuring effect on Arctic predator movements and space use. In this study, we tested the hypothesis that tidewater glacier fronts can influence marine bird foraging patterns and drive spatial segregation among adjacent colonies. We analysed movements of black-legged kittiwakes (Rissa tridactyla) in a glacial fjord by tracking breeding individuals from five colonies. Although breeding kittiwakes were observed to travel up to ca. 280 km from the colony, individuals were more likely to use glacier fronts located closer to their colony and rarely used glacier fronts located farther away than 18 km. Such variation in the use of glacier fronts created fine-scale spatial segregation among the four closest (ca. 7 km distance on average) kittiwake colonies. Overall, our results support the hypothesis that spatially predictable foraging patches like glacier fronts can have strong structuring effects on predator movements and can modulate the magnitude of intercolonial spatial segregation in central-place foragers.

Housing policy, shortage and socio-spatial segregation in the city of Piracicaba (SP)

The objective of the paper is to evaluate the close relationship between public policies of social housing, housing deficit and the process of socio-spatial segregation in the city of Piracicaba, located in the interior of the state of São Paulo, in Brazil, between the years 2000-2020. For this, the method adopted consists of a mixed quali-quantitative approach. Whether due to lack or inadequacy, the housing problem is one of the main urban shortages, whose measurement can be made from the deficit and household inadequacy indicators. To address these issues, housing policies are presented as a state intervention to provide access to housing. However, after years of implementing these policies, the paradox created by them is noted, since, although they were able to face part of the problem, they contributed to the intensification of socio-spatial segregation on the intra-urban scale. In these terms, Piracicaba is an emblematic case of the relationship that is established territorially between these elements, in which socio-spatial segregation is seen as a by-product of social housing policies, under the pretext of coping with housing needs. The investigation therefore seeks to contribute to research on the relationship between housing policies and socio-spatial segregation in medium-sized cities in São Paulo, inserting the concept of deficit as a basic element of this problem.

Kin discrimination modifies fitness, spatial segregation and matrix sharing between strains with low relatedness in Bacillus subtilis biofilms

Microorganisms in nature form multicellular groups called biofilms. In biofilms bacteria embedded in a matrix of extracellular polymeric substances (EPS) interact intensely, due to their proximity to each other. Most studies have investigated genetically homogeneous biofilms, leaving a gap in knowledge on genetically heterogeneous biofilms. Recent insights show that a Gram-positive model bacterium, Bacillus subtilis, discriminates between strains of high (kin) and low (non-kin) phylogenetic relatedness, reflected in merging (kin) and boundaries (non-kin) between swarms. However, it is not clear how kinship between interacting strains affects their fitness, the genotype distribution, and the EPS sharing in floating biofilms (pellicles). To address this gap in knowledge we cultivate B. subtilis strains as mixtures of kin and non-kin strains in static cultures, allowing them to form pellicles. We show here that in non-kin pellicles only one strain’s fitness was reduced; at the same time, strains segregated into larger patches and exhibited decreased matrix sharing, as compared to kin and isogenic pellicles, in which both strains had comparable colony forming units (CFU) counts and more homogenous cell mixing. Overall, our results emphasize kin discrimination (KD) as a social behavior that shapes fitness, spatial segregation and sharing of the extracellular matrix in genetically heterogenous biofilms of B. subtilis.