Spurious Principal Components

The Principal Component Regression is often used to forecast macroeconomic variables when there are many predictors. In this letter, we argue that it makes sense to pre-whiten the predictors before including these in a PCR. With simulation experiments, we show that without such pre-whitening, spurious principal components can appear, and that these can become spuriously significant in a PCR. With an illustrati

Recovering historical inflation data from postal stamps prices

For many developing countries, historical inflation figures are rarely available. We propose a simple method, which aims to recover such figures thereby using prices of postal stamps, issued in earlier years. We illustrate our method for Suriname where annual inflation rates are available for 1961 until 2015, and where fluctuations in inflation rates are prominent. We estimate the inflation rates for the sample 1873 to 1960. Our main finding is that high inflation periods usually last no longer than 2 or 3 years

This time it is different! Or not?

We employ a simple method based on logistic weighted least squares to diagnose which past data are less or more useful for predicting the future course of a variable. A simulation experiment shows its merits. An illustration for monthly industrial production series for 17 countries suggests that earlier data are useful, for the prediction in a crisis period (2006-2011) and for the period after the crisis (201

Aspergillus and the Lung

The filamentous fungus Aspergillus causes a wide spectrum of diseases in the human lung, with Aspergillus fumigatus being the most pathogenic and allergenic subspecies. The broad range of clinical syndromes that can develop from the presence of Aspergillus in the respiratory tract is determined by the interaction between host and pathogen. In this review, an oversight of the different clinical entities of pulmonary aspergillosis is given, categorized by their main pathophysiological mechanisms. The underlying immune processes are discussed, and the main clinical, radiological, biochemical, microbiological, and histopathological findings are summarized.</p

Aspergillus and the Lung

The filamentous fungus Aspergillus causes a wide spectrum of diseases in the human lung, with Aspergillus fumigatus being the most pathogenic and allergenic subspecies. The broad range of clinical syndromes that can develop from the presence of Aspergillus in the respiratory tract is determined by the interaction between host and pathogen. In this review, an oversight of the different clinical entities of pulmonary aspergillosis is given, categorized by their main pathophysiological mechanisms. The underlying immune processes are discussed, and the main clinical, radiological, biochemical, microbiological, and histopathological findings are summarized.</p

Wearing the face veil in Belgium : views and experiences of 27 women living in Belgium concerning the Islamic full face veil and the Belgian ban on face covering

Belgium adopted a legal ban on face covering on 1 June 2011. The current empirical study is part of a broader research project that includes also research documenting local bans and examining the bans from a human rights perspective. The main purpose of the research was to check some of the apparent hypotheses of the Belgian legislator from the perspective of the women wearing a face veil in Belgium. Analysis of the travaux préparatoires revealed three main motives behind the ban: improving (subjective and objective) safety, guaranteeing communication and social cohesion, and protecting women’s rights.4 An academic paper engaging with this research question, will be published elsewhere. The current report is a presentation of the findings of the empirical research as such

ER stress in antigen‐presenting cells promotes NKT cell activation through endogenous neutral lipids

CD1d-restricted invariant natural killer T (iNKT) cells constitute a common glycolipid-reactive innate-like T-cell subset with a broad impact on innate and adaptive immunity. While several microbial glycolipids are known to activate iNKT cells, the cellular mechanisms leading to endogenous CD1d-dependent glycolipid responses remain largely unclear. Here, we show that endoplasmic reticulum (ER) stress in APCs is a potent inducer of CD1d-dependent iNKT cell autoreactivity. This pathway relies on the presence of two transducers of the unfolded protein response: inositol-requiring enzyme-1a (IRE1α) and protein kinase R-like ER kinase (PERK). Surprisingly, the neutral but not the polar lipids generated within APCs undergoing ER stress are capable of activating iNKT cells. These data reveal that ER stress is an important mechanism to elicit endogenous CD1d-restricted iNKT cell responses through induction of distinct classes of neutral lipids

Recovering historical inflation data from postage stamps prices

For many developing countries, historical inflation figures are rarely available. We propose a simple method that aims to recover such figures of inflation using prices of postage stamps issued in earlier years. We illustrate our method for Suriname, where annual inflation rates are available for 1961 until 2015, and where fluctuations in inflation rates are prominent. We estimate the inflation rates for the sample 1873 to 1960. Our main finding is that high inflation periods usually last no longer than 2 or 3 years. An Exponential Generalized Autoregressive Conditional Heteroscedasticity (EGARCH) model for the recent sample and for the full sample with the recovered inflation rates shows the relevance of adding the recovered dat

Evolution and function of the epithelial cell-specific ER stress sensor IRE1β

Barrier epithelial cells lining the mucosal surfaces of the gastrointestinal and respiratory tracts interface directly with the environment. As such, these tissues are continuously challenged to maintain a healthy equilibrium between immunity and tolerance against environmental toxins, food components, and microbes. An extracellular mucus barrier, produced and secreted by the underlying epithelium plays a central role in this host defense response. Several dedicated molecules with a unique tissue-specific expression in mucosal epithelia govern mucosal homeostasis. Here, we review the biology of Inositol-requiring enzyme 1β (IRE1β), an ER-resident endonuclease and paralogue of the most evolutionarily conserved ER stress sensor IRE1α. IRE1β arose through gene duplication in early vertebrates and adopted functions unique from IRE1α which appear to underlie the basic development and physiology of mucosal tissues