It's better to connect and collaborate

In de media is recentelijk veel aandacht voor de schaduwzijde van de democratie en disfunctioneren van het openbaar bestuur. Bij veel mensen is immers sprake van een toenemend wantrouwen in de politiek. Ook wetenschappelijke publicaties signaleren een afnemend vertrouwen in politieke instituties en politici. In het publieke debat over democratie en politiek wordt derhalve regelmatig de vraag gesteld of we het democratisch bestel opnieuw moeten uitvinden. Het dichten van de (vertrouwens)kloof tussen burgers, hun politieke vertegenwoordigers en de ambtelijke uitvoering lijkt aldus een van de meest fundamentele uitdagingen voor alle westerse democratieën. In dit essay verkennen we een mogelijke oplossing voor deze kloof, gebaseerd op praktische ervaringen opgedaan in de gemeente Utrechtse Heuvelrug. Het essay is gebaseerd op de studie ”From competition and collusion to consent-based collaboration: a case study of local democracy”, recentelijk gepubliceerd in de International Journal of Public Administration.In de media is recentelijk veel aandacht voor de schaduwzijde van de democratie en het disfunctioneren van het openbaar bestuur. Bij veel mensen is immers sprake van een toenemend wantrouwen in de politiek, en ook veel wetenschappelijke publicaties signaleren een afnemend vertrouwen in politieke instituties en politici. Het dichten van de kloof tussen burgers, hun politieke vertegenwoordigers en de ambtelijke uitvoering lijkt aldus een van de meest fundamentele uitdagingen voor alle westerse democratieën. In dit essay verkennen we een mogelijke oplossing voor deze kloof, gebaseerd op ervaringen opgedaan in de gemeente Utrechtse Heuvelrug.<br/

Contagion across financial markets during COVID-19: a look at volatility spillovers between the stock and foreign exchange markets in South Africa

The onset of the novel coronavirus pandemic (COVID-19) and previous financial and currency crises have heightened interest in understanding the nature of the interaction of stock market and exchange rate volatility. This paper aims to investigate the interdependence and volatility transmissions between the stock and foreign exchange markets for South Africa over the period 1979:01–2021:08, including the effect the COVID-19 pandemic has had on the interdependence and volatility transmissions. Through the use of bivariate Exponential Generalised Autoregressive Conditional Heteroscedasticity (EGARCH) modelling, the empirical outcomes from this study provide strong evidence in support of the “stock-orientated’ approach, where significant price and volatility spillovers propagate from the stock market into the foreign exchange market; whilst evidence of the “flow-orientated” approach is seen in the second moment and significant shock and asymmetric spillovers from the exchange to stock market are found. The results support the asymmetric and long-range persistence volatility spillover effect and show strong evidence of contagion between stock and foreign exchange market. These spillovers became more pronounced during the COVID-19 pandemic, confirming heightened contagion in these markets during periods of crisis. The results heed important implications for not only policymakers who are concerned by the contagion across financial markets and better regulations of these markets to promote economic growth, but also for investors and fund managers who seek to hedge investment risks in South Africa.The National Research Foundation (NRF).http://www.worldscientific.com/worldscinet/afehj2023Economic

Many bounded versions of undecidable problems are NP-hard

Several physically inspired problems have been proven undecidable; examples are the spectral gap problem and the membership problem for quantum correlations. Most of these results rely on reductions from a handful of undecidable problems, such as the halting problem, the tiling problem, the Post correspondence problem or the matrix mortality problem. All these problems have a common property: they have an NP-hard bounded version. This work establishes a relation between undecidable unbounded problems and their bounded NP-hard versions. Specifically, we show that NP-hardness of a bounded version follows easily from the reduction of the unbounded problems. This leads to new and simpler proofs of the NP-hardness of bounded version of the Post correspondence problem, the matrix mortality problem, the positivity of matrix product operators, the reachability problem, the tiling problem, and the ground state energy problem. This work sheds light on the intractability of problems in theoretical physics and on the computational consequences of bounding a parameter.Comment: 10 pages and 7 pages of appendices, 8 figures; v2,v3: minor change

Is inflation uncertainty a self-fulfilling prophecy in South Africa?

Inflation uncertainty causes macroeconomic ills and instability in the economy. This paper investigates if rising levels of inflation uncertainty serve as a source of higher inflation outcomes or vice versa, to determine if inflation uncertainty is potentially a self-fulfilling prophecy. In addition, this paper examines the impact of inflation targeting, implemented in South Africa in February 2000, on the level of inflation and inflation uncertainty. Using a generalised autoregressive conditional heteroskedasticity (GARCH) and GARCH-in-mean model and monthly data spanning the period 1970:01 to 2022:05, the empirical outcomes from this study suggest the existence of a bi-directional relationship between inflation and inflation uncertainty, with strong evidence in favour of the Friedman–Ball hypothesis and weaker evidence in support of the Cukierman–Meltzer hypothesis. This study also finds that inflation targeting has contributed significantly to reducing the level of inflation and inflation uncertainty since its adoption as policy framework. Time-varying Granger causality tests accounting for instabilities underscore the above results, namely that inflation uncertainty led to increased inflation uncertainty in the full pre-inflation targeting period, whereas increased uncertainty led to increased inflation only during the decade preceding inflation targeting. The results heed important policy implications, as it is imperative that inflation is kept low, stable and predictable.The National Research Foundation of South Africa.http://wileyonlinelibrary.com/journal/sajehj2024EconomicsSDG-08:Decent work and economic growt

Lateral membrane organization as target of an antimicrobial peptidomimetic compound

Antimicrobial resistance is one of the leading concerns in medical care. Here we study the mechanism of action of an antimicrobial cationic tripeptide, AMC-109, by combining high speed-atomic force microscopy, molecular dynamics, fluorescence assays, and lipidomic analysis. We show that AMC-109 activity on negatively charged membranes derived from Staphylococcus aureus consists of two crucial steps. First, AMC-109 self-assembles into stable aggregates consisting of a hydrophobic core and a cationic surface, with specificity for negatively charged membranes. Second, upon incorporation into the membrane, individual peptides insert into the outer monolayer, affecting lateral membrane organization and dissolving membrane nanodomains, without forming pores. We propose that membrane domain dissolution triggered by AMC-109 may affect crucial functions such as protein sorting and cell wall synthesis. Our results indicate that the AMC-109 mode of action resembles that of the disinfectant benzalkonium chloride (BAK), but with enhanced selectivity for bacterial membranes.</p

A Pilot Index for Environmental Policy in the Netherlands

A pilot environmental index for the Netherlands shows a downward trend of environmental pressure in the last decade. The index measures environmental pressure from the policy perspective and the observed downward trend does not imply that environmental quality has increased. The aggregation weights which are used to combine various theme indicators of environmental policy to one overall index are derived from public opinion polls on the concern for environmental problems. Following Hope d.s., who constructed a similar pilot environmental index for the UK, we used the analyogy of compilation of quality of life indices