Interval structure of the Pieri formula for Grothendieck polynomials

We give a combinatorial interpretation of a Pieri formula for double Grothendieck polynomials in terms of an interval of the Bruhat order. Another description had been given by Lenart and Postnikov in terms of chain enumerations. We use Lascoux's interpretation of a product of Grothendieck polynomials as a product of two kinds of generators of the 0-Hecke algebra, or sorting operators. In this way we obtain a direct proof of the result of Lenart and Postnikov and then prove that the set of permutations occuring in the result is actually an interval of the Bruhat order.Comment: 27 page

Actin assembly ruptures the nuclear envelope by prying the lamina away from nuclear pores and nuclear membranes in starfish oocytes.

The nucleus of oocytes (germinal vesicle) is unusually large and its nuclear envelope (NE) is densely packed with nuclear pore complexes (NPCs) stockpiled for embryonic development. We showed that breakdown of this specialized NE is mediated by an Arp2/3-nucleated F-actin 'shell' in starfish oocytes, in contrast to microtubule-driven tearing in mammalian fibroblasts. Here, we address the mechanism of F-actin-driven NE rupture by correlated live-cell, super-resolution and electron microscopy. We show that actin is nucleated within the lamina sprouting filopodia-like spikes towards the nuclear membranes. These F-actin spikes protrude pore-free nuclear membranes, whereas the adjoining membrane stretches accumulate NPCs associated with the still-intact lamina. Packed NPCs sort into a distinct membrane network, while breaks appear in ER-like, pore-free regions. Thereby, we reveal a new function for actin-mediated membrane shaping in nuclear rupture that is likely to have implications in other contexts such as nuclear rupture observed in cancer cells

The Elderly Poor in the EU’s New Member States. ENEPRI Research Reports No. 60, November 2008

To what extent is the financial position of the elderly in the NMS more vulnerable than that of the old member states (or the EU-15), due to a rather unfavourable starting point and the possible impact of pension reforms? This is the main issue of the current research report. It tries to delineate the vulnerability of the income position of elderly people in the NMS, in relation to the demographic, socio-economic and institutional context of these countries. More specifically, the report focuses on: - the current level of income of the elderly in the NMS, and the degree of relative poverty; - the way this position is related to the educational and labour market status of the elderly in the NMS, their retirement behaviour, institutional arrangements (notably the pension system), and demographic developments; - specific problems regarding the income position of possibly ‘marginal’ elderly groups in the NMS (such as single elderly female pensioners)

Do psychological factors play a crucial role in sport performance? – Research on personality and psychological variables of athletes in Hungary

Contemporary research aims to investigate background factors that contribute to successful sport performance. Of these factors the psychological well-being and mental health status should be underlined that have gained a significant role, particularly in the frames of sport psychological counseling. The aim of the present study is to seek for interrelations of psychological variables and sport performance of young athletes, and to reveal what advantages might be utilized in younger ages to strengthen sport performance. No gender differences were found in sport performance; while age showed significant difference. The findings indicated differences of the investigated psychological variables by age and gender. Regression analyses were employed to test how psychological factors predict successfulsport performance. The analyses strengthened the role of age and gender specific factors that should be considered during sport psychological counseling. The benefits should be highlighted in young age in order to ensure more successful performance in adulthood

Closure relations during the plateau emission of Swift GRBs and the fundamental plane

The Neil Gehrels Swift observatory observe Gamma-Ray bursts (GRBs) plateaus in X-rays. We test the reliability of the closure relations through the fireball model when dealing with the GRB plateau emission. We analyze 455 X-ray lightcurves (LCs) collected by \emph{Swift} from 2005 (January) until 2019 (August) for which the redshift is both known and unknown using the phenomenological Willingale 2007 model. Using these fits, we analyze the emission mechanisms and astrophysical environments of these GRBs through the closure relations within the time interval of the plateau emission. Finally, we test the 3D fundamental plane relation (Dainotti relation) which connects the prompt peak luminosity, the time at the end of the plateau (rest-frame), and the luminosity at that time, on the GRBs with redshift, concerning groups determined by the closure relations. This allows us to check if the intrinsic scatter \sigma_{int} of any of these groups is reduced compared to previous literature. The most fulfilled environments for the electron spectral distribution, p>2, are Wind Slow Cooling (SC) and ISM Slow Cooling for cases in which the parameter q, which indicates the flatness of the plateau emission and accounts for the energy injection, is =0 and =0.5, respectively, both in the cases with known and unknown redshifts. We also find that for the sGRBs All ISM Environments with $q=0$ have the smallest \sigma_{int}=0.04 \pm 0.15 in terms of the fundamental plane relation holding a probability of occurring by chance of p=0.005. We have shown that the majority of GRBs presenting the plateau emission fulfil the closure relations, including the energy injection, with a particular preference for the Wind SC environment. The subsample of GRBs that fulfil given relations can be used as possible standard candles and can suggest a way to reduce the intrinsic scatter of these studied relationships.Comment: 44 pages, 23 figures; Accepted to the PASJ to be published soo

Zero-one Schubert polynomials

We prove that if σ∈Sm is a pattern of w∈Sn, then we can express the Schubert polynomial w as a monomial times σ (in reindexed variables) plus a polynomial with nonnegative coefficients. This implies that the set of permutations whose Schubert polynomials have all their coefficients equal to either 0 or 1 is closed under pattern containment. Using Magyar's orthodontia, we characterize this class by a list of twelve avoided patterns. We also give other equivalent conditions on w being zero-one. In this case, the Schubert polynomial w is equal to the integer point transform of a generalized permutahedron

Asymmetric function theory

The classical theory of symmetric functions has a central position in algebraic combinatorics, bridging aspects of representation theory, combinatorics, and enumerative geometry. More recently, this theory has been fruitfully extended to the larger ring of quasisymmetric functions, with corresponding applications. Here, we survey recent work extending this theory further to general asymmetric polynomials.Comment: 36 pages, 8 figures, 1 table. Written for the proceedings of the Schubert calculus conference in Guangzhou, Nov. 201

Agile mechanisms for open data process innovation in public sector organizations: Towards theory building

Process innovation in public organizations is widely documented and has increasingly been the subject of empirical scrutiny. However, no study has attempted to investigate process innovation in open data organizations in public sector. Guided by the Dynamic Capability Theory and based on the detailed study of four open data organizations, we synthesize a theoretical model and a process model for open data process innovation in public sector organizations. Specifically, the study sought to understand how open data process agility is achieved in these organizations. The results highlight the specific agile mechanisms that enable and improve open data process innovation in public sector organizations. The results also provide perspectives on how open data organizations in public sector can change data processes to transform the way they respond to changing demands and external environment

Salmonella exploits HLA-B27 and host Unfolded Protein Responses to promote intracellular replication

Objective Salmonella enterica infections can lead to Reactive Arthritis (ReA), which can exhibit an association with human leucocyte antigen (HLA)-B*27:05, a molecule prone to misfolding and initiation of the unfolded protein response (UPR). This study examined how HLA-B*27:05 expression and the UPR affect the Salmonella life-cycle within epithelial cells. Methods Isogenic epithelial cell lines expressing two copies of either HLA-B*27:05 and a control HLA-B*35:01 heavy chain (HC) were generated to determine the effect on the Salmonella infection life-cycle. A cell line expressing HLA-B*27:05.HC physically linked to the light chain beta-2-microglobulin and a specific peptide (referred to as a single chain trimer, SCT) was also generated to determine the effects of HLA-B27 folding status on S. enterica life-cycle. XBP-1 venus and AMP dependent Transcription Factor (ATF6)-FLAG reporters were used to monitor UPR activation in infected cells. Triacin C was used to inhibit de novo lipid synthesis during UPR, and confocal imaging of ER tracker stained membrane allowed quantification of glibenclamide-associated membrane. Results S. enterica demonstrated enhanced replication with an altered cellular localisation in the presence of HLA-B*27:05.HC but not in the presence of HLA-B*27:05.SCT or HLA-B*35:01. HLA-B*27:05.HC altered the threshold for UPR induction. Salmonella activated the UPR and required XBP-1 for replication, which was associated with endoreticular membrane expansion and lipid metabolism. Conclusions HLA-B27 misfolding and a UPR cellular environment are associated with enhanced Salmonella replication, while Salmonella itself can activate XBP-1 and ATF6. These data provide a potential mechanism linking the life-cycle of Salmonella with the physicochemical properties of HLA-B27 and cellular events that may contribute to ReA pathogenesis. Our observations suggest that the UPR pathway maybe targeted for future therapeutic intervention