Ehrhart polynomials of partial permutohedra

For positive integers m and n, the partial permutohedron P(m,n) is a certain integral polytope in R^m, which can be defined as the convex hull of the vectors from {0,1,...,n}^m whose nonzero entries are distinct. For n = m-1, P(m,m-1) is (after translation by (1,...,1)) the polytope P_m of parking functions of length m, and for n ≥ m, P(m,n) is combinatorially equivalent to an m-stellohedron. The main result of this paper is an explicit expression for the Ehrhart polynomial of P(m,n) for any m and n with n ≥ m-1. The result confirms the validity of a conjecture for this Ehrhart polynomial in arXiv:2207.14253, and the n = m-1 case also answers a question of Stanley regarding the number of integer points in P_m. The proof of the result involves transforming P(m,n) to a unimodularly equivalent polytope in R^{m+1}, obtaining a decomposition of this lifted version of P(m,n) with n ≥ m-1 as a Minkowski sum of dilated coordinate simplices, applying a result of Postnikov for the number of integer points in generalized permutohedra of this form, observing that this gives an expression for the Ehrhart polynomial of P(m,n) with n ≥ m-1 as an edge-weighted sum over graphs (with loops and multiple edges permitted) on m labelled vertices in which each connected component contains at most one cycle, and then applying standard techniques for the enumeration of such graphs

Novel pheromone-mediated reproductive behaviour in the stag beetle, Lucanus cervus

The iconic European stag beetle (Lucanus cervus) (Coleoptera: Lucanidae) is one of the largest terrestrial beetles in Europe. Due to decreasing population numbers, thought to be a consequence of habitat loss, this beetle has become a near-threatened species across much of Europe, and a reliable monitoring system is required to measure its future population trends. As part of a programme aimed at conserving UK populations, we have investigated the chemical ecology of the beetle, with a view to developing an efficient semiochemical-based monitoring system. Such a scheme will be beneficial not only in the UK but across the European range of the species, where the beetle is of conservation concern. Here, we report on a surprising discovery of a male-produced pheromone, which provokes initial sexual receptivity in females, and which has not been previously identified in the animal kingdom. Furthermore, we assign sex pheromone function to a previously described female-specific compound

Towards efficient image and video style transfer via distillation and learnable feature transformation

Despite the recent rapid development of neural style transfer, existing style transfer methods are still somewhat inefficient or have a large model size, which limits their application on computational resource limited devices. The major problem lies in that they usually adopt a pre-trained VGG-19 backbone which is relatively large or the feature transformation module is computationally heavy. To address above problems, we propose a DIstillation based Style Transfer framework (called DIST) in conjunction with an efficient feature transformation module for arbitrary image and video style transfer. The distillation module can lead to a highly compressed backbone network, which is 15.95 smaller than the VGG-19 based backbone. The proposed feature transformation is capable of transforming the content features in an extremely efficient feed forward pass. For video style transfer, the above framework is further combined with a temporal consistency regularization loss. Extensive experiments show that the proposed method is superior over the state-of-the-art image and video style transfer methods, even with a much smaller model size

The business of Universities: A case study of halls of residence

In this article, we discuss the changing modes of provision of English Universities’ halls of residence from University provision to a complex marketplace in which private provision dominates. We frame our analysis around five themes familiar to discussions of privatisations of public sector institutions: financialisation, affordability, infrastructure, regulation, and partnerships. We draw on our original research, which comprises a survey of 50 universities, readings of the corporate reports of the leading providers, and seven key stakeholder interviews. This data enables us to illustrate concerns about the effects on students and the University sector in England as a result of the shift in mode of provision

The role of lived experience eye care champions in improving awareness and access to eye care services for people with learning disabilities and/or autism

Background: Documented inequalities in access to eye care for people with learning disabilities and/or autism are caused by poor uptake of primary eye care services, poor identification of eye problems, lack of signposting and reasonable adjustments of existing services, concerns about costs of care and the low priority historically given to these issues in eye care policy at a regional and national level. In 2019, the charity SeeAbility employed four eye care champions (ECCs) with lived experience of learning disability and/or autism to work in local communities in London and the Northwest of England. They provided peer-to-peer support on understanding the need for good eye health and engaged with policy makers, and learning disability, autism and eye care professionals at the local, regional and national levels to influence both the clinical practice of individual practitioners (within existing service/pathway models) and more widely to influence the commissioning of the Easy Eye Care pathway. This study explores the experiences of these ECCs. Methods: The study was conducted in April and May 2023. A case study approach was used to describe the experiences of the ECCs from March 2019 to March 2023. Data from structured interviews with the four ECCs and workload analysis were triangulated to provide a multifaceted understanding of this novel health promotion project. Findings: The ECCs found the role useful and reported that confidence in their practice and impact grew with time but they required ongoing support in the role. A good understanding of the promotional messages was reported. Developing a good network of contacts at an early stage, both people with learning disabilities and healthcare professionals, was key. Relationships with professionals were supportive and positive and a positive emotive response to their lived experience was reported in these interactions. Conclusions: From the perspective of the ECCs, the role is useful and beneficial. The work suggests some key recommendations for future development which include planning to build networks, support in presentation and communications skills and defining key messages and knowledge. Confidence of the ECCs builds with time in the role but also needs support the emotive impact of their lived experiences on audiences is highlighted. There is a need to evaluate how the programme is perceived by those who interact with it and how it changes behaviours which leads to better health outcomes

Dual-constraint coarse-to-fine network for camouflaged object detection

Camouflaged object detection (COD) is an important yet challenging task, with great application values in industrial defect detection, medical care, etc. The challenges mainly come from the high intrinsic similarities between target objects and background. In this paper, inspired by the biological studies that object detection consists of two steps, i.e., search and identification, we propose a novel framework, named DCNet, for accurate COD. DCNet explores candidate objects and extra object-related edges through two constraints (object area and boundary) and detects camouflaged objects in a coarse-to-fine manner. Specifically, we first exploit an area-boundary decoder (ABD) to obtain initial region cues and boundary cues simultaneously by fusing multi-level features of the backbone. Then, an area search module (ASM) is embedded into each level of the backbone to adaptively search coarse regions of objects with the assistance of region cues from the ABD. After the ASM, an area refinement module (ARM) is utilized to identify fine regions of objects by fusing adjacent-level features with the guidance of boundary cues. Through the deep supervision strategy, DCNet can finally localize the camouflaged objects precisely. Extensive experiments on three benchmark COD datasets demonstrate that our DCNet is superior to 12 state-of-the-art COD methods. In addition, DCNet shows promising results on two COD-related tasks, i.e., industrial defect detection and polyp segmentation

Managerial ability and firm value: A new perspective

Using a sample of U.S. firms over three decades, we examine whether the efficiency with which managers generate revenue has an impact on firm value. We find that managerial ability is positively related to firm value such that one standard deviation increase in ability is associated with a 5.7% increase in firm value relative to the mean level. Importantly, by exploiting exogenous CEO turnover, we establish causality between managerial ability and firm value. This relation is stronger in the presence of corporate governance mechanisms, such as institutional investors and financial analysts. We also document a reduction in value-destroying practices - such as earnings management - in firms with more efficient managers

Polygenic variation underlying educational attainment and attention-deficit/hyperactivity disorder indexes behavior ratings of executive functions in child psychiatry outpatients

Objective: We leveraged common genetic variation underlying ADHD, educational attainment (EA) and cognition (COG) to understand the nature of the Behavior Rating Inventory for Executive Functions (BRIEF) and its relationship to academic functioning. Method: Participants were 991 youth, ages 7 to 17, consecutively referred for neuropsychiatric evaluation. Polygenic scores (PGS) for ADHD, EA, and COG were related to the BRIEF using regression analyses. Structural equation models were used to examine the associations between the PGS, BRIEF and academic outcomes (math, reading, and special education services [EDPLAN]). Results: After modeling the PGS together, only the EA and ADHD PGS significantly associated with the BRIEF. The BRIEF partially mediated the relationships between EA PGS with math and EDPLAN and fully mediated the relationship between ADHD PGS and EDPLAN. Conclusion: Genetic data extend evidence that the BRIEF measures a construct relevant to educational success that differs from what is indexed by cognitive testing

Dispersive transverse waves for a strain-limiting continuum model

It is well known that propagation of waves in homogeneous linearized elastic materials of infinite extent is not dispersive. Motivated by the work of Rubin, Rosenau, and Gottlieb, we develop a generalized continuum model for the response of strain-limiting materials that are dispersive. Our approach is based on both a direct inclusion of Rivlin–Ericksen tensors in the constitutive relations and writing the linearized strain in terms of the stress. As a result, we derive two coupled generalized improved Boussinesq-type equations in the stress components for the propagation of pure transverse waves. We investigate the traveling wave solutions of the generalized Boussinesq-type equations and show that the resulting ordinary differential equations form a Hamiltonian system. Linearly and circularly polarized cases are also investigated. In the case of unidirectional propagation, we show that the propagation of small-but-finite amplitude long waves is governed by the complex Korteweg–de Vries (KdV) equation

Maternal depressive symptoms and young people's higher education participation and choice of university: Evidence from a longitudinal cohort study

Background Participation in higher education has significant and long-lasting consequences for people's socioeconomic trajectories. Maternal depression is linked to poorer educational achievement for children in school, but its impact on university attendance is unclear. Methods In an English longitudinal cohort study (N = 8952), we explore whether young people whose mothers experienced elevated depressive symptoms are less likely to attend university, and the role of potential mediators in the young person: educational achievement in school, depressive symptoms, and locus of control. We also examine whether maternal depressive symptoms influence young people's choice of university, and non-attendees' reasons for not participating in higher education. Results Young people whose mothers experienced more recurrent depressive symptoms were less likely to attend university (OR = 0.88, CI = 0.82,0.94, p < 0.001) per occasion of elevated maternal depressive symptoms) after adjusting for confounders. Mediation analysis indicated this was largely explained by educational achievement in school (e.g., 82.7 % mediated by age 16 achievement) and locus of control at 16. There was mixed evidence for an impact on choice of university. For participants who did not study at university, maternal depressive symptoms were linked to stating as a reason having had other priorities to do with family or children (OR: 1.17, CI = 1.02,1.35). Limitations Lack of data on the other parent's depression, loss to follow-up, possibly selective non-response. Conclusions Young people whose mothers experience elevated depressive symptoms on multiple occasions are less likely to participate in higher education; educational achievement in secondary school, but not the young people's own depressive symptoms, substantially mediated the effect