Sharp measure contraction property for generalized H-type Carnot groups

We prove that H-type Carnot groups of rank $k$ and dimension $n$ satisfy the $\mathrm{MCP}(K,N)$ if and only if $K\leq 0$ and $N \geq k+3(n-k)$. The latter integer coincides with the geodesic dimension of the Carnot group. The same result holds true for the larger class of generalized H-type Carnot groups introduced in this paper, and for which we compute explicitly the optimal synthesis. This constitutes the largest class of Carnot groups for which the curvature exponent coincides with the geodesic dimension. We stress that generalized H-type Carnot groups have step 2, include all corank 1 groups and, in general, admit abnormal minimizing curves. As a corollary, we prove the absolute continuity of the Wasserstein geodesics for the quadratic cost on all generalized H-type Carnot groups.Comment: 18 pages. This article extends the results of arXiv:1510.05960. v2: revised and improved version. v3: final version, to appear in Commun. Contemp. Mat

An embedded shock-fitting technique on unstructured dynamic grids

In this paper, a new shock-fitting technique based on unstructured dynamic grids is proposed to improve the performances of the unstructured “boundary” shock-fitting technique developed by Liu and co-workers in [1, 2]. The main feature of this new technique, which we call the “embedded” shock-fitting technique, is its capability to insert or remove shocks or parts thereof during the calculation. This capability is enabled by defining subsets of grid-points (mutually connected by lines) which behave as either “common”- or “shock”-points, shock-waves being made of an ordered collection of shock-points. Two different sets of flow variables, corresponding to the upstream and downstream sides of the shocks, are assigned to the shock-points, which may be switched to common- and back to shock-points, a feature that allows to vary the length of the existing shocks and/or make new shock-branches appear. This paper illustrates the algorithmic features of this new technique and presents the results obtained when simulating both steady and un-steady, two-dimensional flows

Talking about a nanny nation: investigating the rhetoric framing public health debates in Australian news media

Objectives and importance of study: News media portrayal of public health issues influences public opinion, policy action and decision making. This study aimed to analyse the use of 'nanny state' frames in Australian news media coverage; identify the stakeholders invoking this frame; determine which public health-related policies attract such framing; and investigate whether 'nanny state' framing is directly challenged in news coverage. STUDY TYPE: A qualitative framing analysis. METHODS: Articles featuring the term 'nanny state' that were published in Australian print newspapers during matched periods between March and September in 2017 and 2018 were sourced through Factiva, coded and analysed for content and 'nanny state' framing. Content analysis was used to identify any public health-related issues that the terminology nanny state was applied to, and who was portrayed as imposing the nanny state. Frame analysis was used to analyse what meanings are co-presented with the phrase nanny state. RESULTS: Out of 81 print newspaper articles that included the term 'nanny state', 19% linked the term to restricting personal choice or creating dissatisfaction with too many health-related rules and regulations broadly, across a range of issues, including: bike helmets, e-cigarettes, firearm restrictions, seatbelts, pool fences and smoking bans. The next most frequent links were to regulations on alcohol (17%), road safety (14%), obesity-related issues (7%) and tobacco control (6%). Of the 81 articles, 53% appeared in news publications owned by News Corporation Australia, 20% in Fairfax Media (Nine Entertainment) publications, 17% in Daily Mail and General Trust and 10% in publications owned by other organisations. Governments were the entity most frequently framed as imposing the nanny state. Most nanny state framings (73%) were negative towards public health controls and focused on policies and regulations. Nanny state was portrayed as an assault on freedom and choice (14%) and used to attack proponents of nanny state controls (11%), while few articles framed the nanny state (7%) in a favourable light. CONCLUSIONS: 'Nanny state' is a rhetorical device commonly used in Australian news media that may contribute to discrediting of the regulation of a range of health-related issues. News Corp publications are a major propagator of nanny state rhetoric in Australian newspaper media. Public health advocates are not commonly represented within nanny state debates within the news media

Extrapolated shock fitting for two-dimensional flows on structured grids

Over the years the development of structured-grid shock-fitting techniques faced two main problems: the handling of a moving discontinuity on a fixed background grid and the capability of simulating complex flow configurations. In the proposed work, the authors present a new shock-fitting technique for structured-grid solvers that is capable of overcoming the limitations that affected the different approaches originally developed. The technique presented here removes the tight link between grid topology and shock topology, which characterizes previous shock fitting as well as front tracking methods. This significantly simplifies their implementation and more importantly reduces the computational overhead related to these geometrical manipulations. Interacting discontinuities and shocks interacting with a solid boundary are discussed and analyzed. Finally, a quantitative investigation of the error reduction obtained with the approach proposed via a global grid convergence analysis is presented

A new computational technique for re-entry flow calculations based upon a shock-fitting technique for unstructured grids

An in-house developed, 2D/3D unstructured CFD solver has been extended to deal with a mixture of thermally perfect gases in chemical non-equilibrium. The Euler equations have been coupled with a state-to-state kinetic model for argon plasma. The spatial discretization uses compact stencil Residual Distribution Schemes and shock waves can be modelled using either shock-capturing or shock-fitting. Promising results have been obtained using the shock-fitting approach for a 2D hypersonic flow past the fore-body of a circular cylinder

Widening the debate about conflict of interest: addressing relationships between journalists and the pharmaceutical industry

The phone-hacking scandal that led to the closure of the News of the World newspaper in Britain has prompted international debate about media practices and regulation. It is timely to broaden the discussion about journalistic ethics and conduct to include consideration of the impact of media practices upon the population’s health. Many commercial organizations cultivate relationships with journalists and news organizations with the aim of influencing the content of health-related news and information communicated through the media. Given the significant influence of the media on the health of individuals and populations, we should be alert to the potential impact of industry-journalist relationships on health care, health policy and public health. The approach taken by the medical profession to its interactions with the pharmaceutical industry provides a useful model for management of industry influence. Keywords Journalism, mass media, pharmaceutical industry, conflict of interest, ethics, media regulationNHMR

The role of fundamental solution in Potential and Regularity Theory for subelliptic PDE

In this survey we consider a general Hormander type operator, represented as a sum of squares of vector fields plus a drift and we outline the central role of the fundamental solution in developing Potential and Regularity Theory for solutions of related PDEs. After recalling the Gaussian behavior at infinity of the kernel, we show some mean value formulas on the level sets of the fundamental solution, which are the starting point to obtain a comprehensive parallel of the classical Potential Theory. Then we show that a precise knowledge of the fundamental solution leads to global regularity results, namely estimates at the boundary or on the whole space. Finally in the problem of regularity of non linear differential equations we need an ad hoc modification of the parametrix method, based on the properties of the fundamental solution of an approximating problem

Trade, Finance and Endogenous Firm Heterogeneity

We study how financial frictions affect firm-level heterogeneity and trade. We build a model in which productivity differences across monopolistically competitive firms are endogenous and depend on investment decisions at the entry stage. By increasing entry costs, financial frictions lower the exit cutoff and hence the value of investing in bigger projects with more dispersed outcomes. As a result, financial frictions make firms smaller and more homogeneous, and hinder the volume of exports. Export opportunities, instead, shift expected profits to the tail and increase the value of technological heterogeneity. We test these predictions using comparable measures of sales dispersion within 365 manufacturing industries in 119 countries, built from highly disaggregated US import data. Consistent with the model, financial development increases sales dispersion, especially in more financially vulnerable industries; sales dispersion is also increasing in measures of comparative advantage. These results help explaining the effect of financial development and factor endowments on export sales.We acknowledge financial support from the Barcelona GSE, the Spanish Ministry of Economy, and Competitiveness (ECO2014-55555-P and ECO2014-59805-P), and the Catalan AGAUR (2014-SGR-546)

"Is this case of a very rare disease work-related?" A review of reported cases of Pacinian neuroma.

Objective In response to a request for a medicolegal opinion from an orthopaedic technician with pacinian neuroma of the hand, we conducted a systematic review of reported cases designed to assess whether this rare disease could be considered to be work-related.Methods We used Medline, Embase, Google Scholar, Google, and a manual search to identify reports of histologically confirmed pacinian neuroma of the hand manifesting after 15 years of age. Cases with available information (from article/authors) on personal history were considered eligible. We tabulated information on age/gender; localization and histopathologic features; signs/symptoms; history of local trauma; occupation, sports/hobbies or other physical exposures; right- or left-handedness; and outcome.Results We found 44 eligible cases (including the present referral). Of these, 21 (48%) followed a trauma [<6 months from onset/presentation (N=7); 0.5\u20132 years from onset (N=6); 652 years from onset (N=7); and timing unknown (N=1)] involving the same anatomic site. Three of these 21 traumas definitely occurred at work, and a further 2 cases occurred at the site of definite work-related repetitive microtrauma.Conclusions The results reinforce the concept that pacinian neuroma of the hand can follow local trauma or repetitive microtrauma. Implicated traumas were either recent or remote, and they sometimes occurred while performing manual tasks at work. We concluded that the referred case could plausibly be considered work-related