Stabilita a změna osobních hodnot u lidí s různými trajektoriemi životní dráhy: longitudinální studie

Background. Previous research on the stability of personal values in the context of life transitions has usually focused on the presence of a single transition. However, life transitions in everyday life occur simultaneously with other life transitions. The aim of this longitudinal study was therefore to identify different trajectories of life transitions in young adults and to compare the stability of their personal values. Method. In the first wave of research, participants were 18-33 years old; in the second wave, they were 29-43 years old (N = 632; 392 women). In both waves, they completed Schwartzʼs Portrait Value Questionnaires (PVQ); in the second wave, they completed the Life History Calendar focusing on the presence of entry into life transitions. Results. Latent class analysis revealed two trajectories: Experienced transitions (people who experienced all observed transitions) and Partially experienced transitions (people who experienced only entry into regular employment and part of them entered cohabitation). Differential stability of personal values occurred in both trajectories. The differences in the stability of values found between the individual trajectories were insignificant, except for personal values universalism and tradition. Although before entry into life transitions, personal values were not significant predictors of belonging to a particular trajectory, after their experiencing people with the Experienced transitions trajectory more often reached lower levels of values associated with openness to change.

Differential stability properties in convex scalar and vector optimization

This paper focuses on formulas for the ε-subdifferential of the optimal value function of scalar and vector convex optimization problems. These formulas can be applied when the set of solutions of the problem is empty. In the scalar case, both unconstrained problems and problems with an inclusion constraint are considered. For the last ones, limiting results are derived, in such a way that no qualification conditions are required. The main mathematical tool is a limiting calculus rule for the ε-subdifferential of the sum of convex and lower semicontinuous functions defined on a (non necessarily reflexive) Banach space. In the vector case, unconstrained problems are studied and exact formulas are derived by linear scalarizations. These results are based on a concept of infimal set, the notion of cone proper set and an ε-subdifferential for convex vector functions due to Taa.

Role of DegQ in differential stability of flagellin subunits in Vibrio vulnificus

Biofilm formation of Vibrio vulnificus is initiated by adherence of flagellated cells to surfaces, and then flagellum-driven motility is not necessary during biofilm maturation. Once matured biofilms are constructed, cells become flagellated and swim to disperse from biofilms. As a consequence, timely regulations of the flagellar components’ expression are crucial to complete a biofilm life-cycle. In this study, we demonstrated that flagellins’ production is regulated in a biofilm stage-specific manner, via activities of a protease DegQ and a chaperone FlaJ. Among four flagellin subunits for V. vulnificus filament, FlaC had the highest affinities to hook-associated proteins, and is critical for maturating flagellum, showed the least susceptibility to DegQ due to the presence of methionine residues in its DegQ-sensitive domains, ND1 and CD0. Therefore, differential regulation by DegQ and FlaJ controls the cytoplasmic stability of flagellins, which further determines the motility-dependent, stage-specific development of biofilms.

Biased removal and loading of centromeric histone H3 during reproduction underlies uniparental genome elimination

Uniparental genome elimination is a dramatic case of centromeric failure, resulting in the postzygotic loss of a parental chromosome set. Genome partitioning during cell division relies on centromere attachment to spindle fibers through kinetochores. Centromeres are epigenetically specified by CENP-A (CENH3), a conserved centromeric specific histone H3 variant. In Arabidopsis, CENH3 modification results in haploid inducers, whose genome is eliminated frequently when crossed to the wild type. To investigate the underlying mechanism, we dissected the timing and molecular features of genome elimination. In zygotes and early embryos from genome elimination crosses, CENH3 occupied only the centromeres contributed by the wild-type parent. Haploid inducer chromosomes had defective kinetochores and missegregated, often forming micronuclei. This uniparental loss of centromere identity is initiated by the removal of altered CENH3 at fertilization, while wild-type CENH3 persists and maintains strong centromeric identity. Weak centromeres were capable of rebuilding functional kinetochores, but often failed when in competition with normal ones. We induced a similar weak state by mitotic dilution of wild-type CENH3. Furthermore, weakness was suppressed by crosses of haploid inducers to other variants of haploid inducers, and enhanced by mutations in VIM1, a ubiquitin ligase known to modify CENH3 and centromeric DNA methylation.. The differential stability of altered CENH3 during reproduction has important genetic and evolutionary implications.

Dynamics of binding ability prediction between spike protein and human ACE2 reveals the adaptive strategy of SARS-CoV-2 in humans

SARS-CoV-2 (severe acute respiratory syndrome coronavirus 2) is a novel coronavirus causing the COVID-19 pandemic in 2020. High adaptive plasticity on the spike protein of SASR-CoV-2 enables it to transmit across different host species. In the present study, we collected 2092 high-quality genome sequences of SARS-CoV-2 from 160 regions in over 50 countries and reconstructed their phylogeny. We also analyzed the polymorphic interaction between spike protein and human ACE2 (hACE2). Phylogenetic analysis of SARS-CoV-2 suggests that SARS-CoV-2 is probably originated from a recombination event on the spike protein between a bat coronavirus and a pangolin coronavirus that endows it humans infectivity. Compared with other regions in the S gene of SARS-CoV-2, the direct-binding sites of the receptor-binding domain (RBD) is more conserved. We focused on 3,860 amino acid mutations in spike protein RBD (T333-C525) of SARS-CoV-2 and simulated their differential stability and binding affinity to hACE2 (S19-D615). The results indicate no preference for SARS-CoV-2 infectivity on people of different ethnic groups. The variants in the spike protein of SARS-CoV-2 may also be a good indicator demonstrating the transmission route of SARS-CoV-2 from its natural reservoir to human hosts.

Cepo uncovers cell identity through differential stability

We present Cepo, a method to generate cell-type-specific gene statistics of differentially stable genes from single-cell RNA-sequencing (scRNA-seq) data to define cell identity. Cepo outperforms current methods in assigning cell identity and enhances several cell identification applications such as cell-type characterisation, spatial mapping of single cells, and lineage inference of single cells.

Catalytic bias in oxidation–reduction catalysis

Under steady state conditions, the differential stability of reaction intermediates can alter the rate and the direction of a catalytic process regardless the overall underlying thermodynamic driving force.