Working time in 2019-2020

Aquesta publicació s'elabora a partir de les contribucions de cadascú dels membres nacionals que integren la Network of Eufound Correspondent. Pel cas d'Espanya la contribució ha estat realitzada per l'Alejandro GodinoThe most relevant changes in working time regulation in Europe in 2019 and 2020 addressed challenges arising as a result of the COVID-19 pandemic. Most focused on short-time working schemes, on approaches to teleworking for those able to work from home and on regulations to ensure the safe provision of essential services. In 2020, the average collectively agreed working week in the EU stood at 37.8 hours. Across the sectors analysed in the report, the collectively agreed normal working week was shortest in public administration (38 hours) and longest in transport (39.2 hours). Paid annual leave entitlement (taking into account those set through collective bargaining) stood at an average of 24.5 days across the EU. Key topics for discussion in all Member States during the COVID-19 pandemic included dealing with the impact of changes in working hours on different groups of workers and the role of working time in supporting economic recovery and job creation

Status of replication according to the PN stage and time of fixation.

<p>Embryos were first sorted according to their PN stage and the timing of their fixation. Then, for each category, embryos were sorted again according to their replication staining. Early PN3 embryos are exclusively in pre-replication, PN3 are in majority in early replication, early PN4 are mostly in mid/late replication and most of the late PN4 have completed replication.</p

Relationship between DNA demethylation and replication.

<p>A) Quantification of the 5MeC paternal/maternal ratio in control (methanol) and aphidicolin treated embryos with representative images (z-projections of 3D-stacks). Images were rotated if necessary to have the maternal PN on the left and the paternal PN on the right. Scale Bar: 10 µm. B) Separate quantification of 5MeC for both pronuclei in control and aphidicolin treated embryos. 4 experiments were performed and a total of 59 (5+17+25+12) control embryos versus 61 (7+18+22+14) aphidicolin treated ones were quantified.</p

Statistical analysis of 3D images detects regular spatial distributions of centromeres and chromocenters in animal and plant nuclei.

In eukaryotes, the interphase nucleus is organized in morphologically and/or functionally distinct nuclear "compartments". Numerous studies highlight functional relationships between the spatial organization of the nucleus and gene regulation. This raises the question of whether nuclear organization principles exist and, if so, whether they are identical in the animal and plant kingdoms. We addressed this issue through the investigation of the three-dimensional distribution of the centromeres and chromocenters. We investigated five very diverse populations of interphase nuclei at different differentiation stages in their physiological environment, belonging to rabbit embryos at the 8-cell and blastocyst stages, differentiated rabbit mammary epithelial cells during lactation, and differentiated cells of Arabidopsis thaliana plantlets. We developed new tools based on the processing of confocal images and a new statistical approach based on G- and F- distance functions used in spatial statistics. Our original computational scheme takes into account both size and shape variability by comparing, for each nucleus, the observed distribution against a reference distribution estimated by Monte-Carlo sampling over the same nucleus. This implicit normalization allowed similar data processing and extraction of rules in the five differentiated nuclei populations of the three studied biological systems, despite differences in chromosome number, genome organization and heterochromatin content. We showed that centromeres/chromocenters form significantly more regularly spaced patterns than expected under a completely random situation, suggesting that repulsive constraints or spatial inhomogeneities underlay the spatial organization of heterochromatic compartments. The proposed technique should be useful for identifying further spatial features in a wide range of cell types

Image processing and 3D modeling of rabbit nuclei.

<p>(AA′) Single confocal microscopy sections. (A) Rabbit blastocyst nucleus, HP1β (red) and CENP (green) immunolabeling. (A′) Rabbit nucleus of a mammary gland epithelial cell, CENP (green) immunolabeling and DAPI counterstaining (blue). (BB′) Gaussian gradient magnitudes of nuclear staining images (HP1β or DAPI). (CC′) Overlay of nuclear contours (white) and DNA/HP1β staining. Contours were obtained after applying a Gaussian gradient-weighted threshold to nuclear staining images. (DD′) Enhancement of centromeric spots using top-hat filtering of CENP images. (EE′) Single section overlay of nuclear contours (white), CENP labeling, and centromeres (color) obtained by thresholding DD′. Note that centromeres are distributed within the whole nucleus, and not confined to the nuclear periphery. (FF′) Resulting 3D models with centromeres in dark blue. Scale bar: 2 µm.</p

Histograms of the F-function-related spatial distribution index, within the five cellular types.

<p>For each nucleus, the SDI is the probability of observing, under a completely random binomial point pattern, a difference at least as large as that observed between the empirical and the CRBPP mean F-functions.</p

Analysis of the spatial distribution of centromere/chromocenter: results of statistical tests.

<p>For F- and G-functions, the table gives the statistic (D) and the p-value of the bilateral Kolmogorov-Smirnov test that was used to assess differences between observed distributions and completely random patterns. The table also gives the statistic (tau) and the p-value of the Kendall's rank correlation test that was used to assess a link between observed centromere/chromocenter spatial distributions and nucleus flatness. n: number of analyzed nuclei.</p