Representational similarity analysis offers a preview of the noradrenergic modulation of long-term fear memory at the time of encoding

Neuroimaging research on emotional memory has greatly advanced our understanding of the pathogenesis of anxiety disorders. While the behavioral expression of fear at the time of encoding does not predict whether an aversive experience will evolve into long-term fear memory, the application of multi-voxel pattern analysis (MVPA) for the analysis of BOLD-MRI data has recently provided a unique marker for memory formation. Here, we aimed to further investigate the utility of this marker by modulating the strength of fear memory with an α2-adrenoceptor antagonist (yohimbine HCl). Fifty-two healthy participants were randomly assigned to two conditions - either receiving 20 mg yohimbine or a placebo pill (double-blind) - prior to differential fear conditioning and MRI-scanning. We examined the strength of fear associations during acquisition and retention of fear (48 h later) by assessing the similarity of BOLD-MRI patterns and pupil dilation responses. Additionally, participants returned for a follow-up test outside the scanner (2-4 weeks), during which we assessed fear-potentiated startle responses. Replicating our previous findings, neural pattern similarity reflected the development of fear associations over time, and unlike average activation or pupil dilation, predicted the later expression of fear memory (pupil dilation 48 h later). While no effect of yohimbine was observed on markers of autonomic arousal, including salivary α-amylase (sAA), we obtained indirect evidence for the noradrenergic enhancement of fear memory consolidation: sAA levels showed a strong increase prior to fMRI scanning, irrespective of whether participants had received yohimbine, and this increase correlated with the subsequent expression of fear (48 h later). Remarkably, this noradrenergic enhancement of fear was associated with changes in neural response patterns at the time of learning. These findings provide further evidence that representational similarity analysis is a sensitive tool for studying (enhanced) memory formation

Cough due to ace inhibitors: A case control study using automated general practice data

Objectives: To determine the risk of coughing as an adverse reaction to ACE inhibitors under everyday circumstances in a large population, and to study whether this adverse effect was duration or dose dependent. Design: A population-based case-control study. Setting: Ten general practices of 14 Dutch general practitioners (GP), in which all consultations, morbidity and medical interventions, including drugs prescribed, were registered over the 18 month period from 1st September, 1992 to 1st March, 1994. Subjects: 1458 patients with incident coughing and up to four controls per case were obtained (total 4182 controls), matched for GP. All cases and controls were 20 years or older and had no record of respiratory infection, influenza, tuberculosis, asthma, chronic bronchitis, emphysema, congestive heart failure, sinusitis, laryngitis, haemoptysis or respiratory neoplasms during the study period. Results: Cases were 2.1-times more likely than controls to have been exposed to ACE inhibitors (95% CI 1.5-3.1), but after adjustment the odds ratio was 1.4 (95% CI 0.9-2.1). The crude odds ratio for captopril was 1.3 (95% CI 0.7-2.5), for enalapril 2.6 (95% CI 1.6-4.2) and for lisinopril 2.0 (95% CI 0.5-9.3). The adjusted odds ratio for captopril was 0.9 (95% CI 0.4-1.7), for enalapril 1.7 (95% CI 1.03-2.8) and for lisinopril 1.7 (95% CI 0.4-7.9). For patients who had been on ACE inhibitor treatment for no longer than 2 months the odds ratio was 4.8 (95% CI 1.7-13.3). The odds ratio declined to 2.0 (95% CI 1.1-3.8) for those who had taken an ACE inhibitor for 2-6 months, and to 1.6 (95% CI 0.9-2.7) for those on ACE-inhibitors for more than 6 months. Conclusion: The risk of coughing was increased twofold among ACE inhibitor users, but the odds ratios were no longer significant after controlling for several confounding factors. The risk of developing cough due to ACE-inhibitors declines with the duration of treatment, possibly due to depletion of susceptible persons

Weak energy condition violation and superluminal travel

Recent solutions to the Einstein Field Equations involving negative energy densities, i.e., matter violating the weak-energy-condition, have been obtained, namely traversable wormholes, the Alcubierre warp drive and the Krasnikov tube. These solutions are related to superluminal travel, although locally the speed of light is not surpassed. It is difficult to define faster-than-light travel in generic space-times, and one can construct metrics which apparently allow superluminal travel, but are in fact flat Minkowski space-times. Therefore, to avoid these difficulties it is important to provide an appropriate definition of superluminal travel.Comment: 15 pages, 3 figures, LaTeX2e, Springer style files -included. Contribution to the Proceedings of the Spanish Relativity Meeting-2001 (Madrid, September 2001

The Three-Step Workflow: A Pragmatic Approach to Allocating Academic Hospitals’ Affiliations for Bibliometric Purposes

This paper presents a method for classifying the varying degrees of interdependency between academic hospitals and universities in the context of the Leiden Ranking. A key question for ranking universities is whether or not to allocate the publication output of affiliated hospitals to universities.Hospital nomenclatures vary worldwide to denote some form of collaboration with a university: academic hospitals, teaching hospitals, university hospitals, and academic medical centres do not correspond to universally standard definitions. Thus, rather than seeking a normative definition of academic hospitals, we are proposing a workflow that aligns the university-hospital relationship with one of three general models: full integration of the hospital and the medical faculty into a single organization; health science centres in which hospitals and medical faculty remain separate entities albeit within the same governance structure; and structures in which universities and hospitals are separate entities which collaborate with one another. This classification system provides a standard by which we can allocate publications which note affiliations with academic hospitals.Our three-step workflow effectively translates the three above-mentioned models into two types of instrumental relationships for the assignation of publications: “associate” and “component”. When a hospital and a medical faculty are fully integrated or when a hospital is part of a health science centre, the relationship is classified as component. When a hospital follows the model of collaboration and support, the relationship is classified as associate. The compilation of data following these standards allows for a more uniform comparison between worldwide educational and research systems.Seventh Framework Programme (FP7)313082Merit, Expertise and Measuremen

Subclinical hypothyroidism is an independent risk factor for atherosclerosis and myocardial infarction in elderly women: the Rotterdam Study

BACKGROUND: Overt hypothyroidism has been found to be associated with cardiovascular disease. Whether subclinical hypothyroidism and thyroid autoimmunity are also risk factors for cardiovascular disease is controversial. OBJECTIVE: To investigate whether subclinical hypothyroidism and thyroid autoimmunity are associated with aortic atherosclerosis and myocardial infarction in postmenopausal women. DESIGN: Population-based cross-sectional study. SETTING: A district of Rotterdam, The Netherlands. PARTICIPANTS: Random sample of 1149 women (mean age +/- SD, 69.0 +/- 7.5 years) participating in the Rotterdam Study. MEASUREMENTS: Data on thyroid status, aortic atherosclerosis, and history of myocardial infarction were obtained at baseline. Subclinical hypothyroidism was defined as an elevated thyroid-stimulating hormone level (>4.0 mU/L) and a normal serum free thyroxine level (11 to 25 pmol/L [0.9 to 1.9 ng/dL]). In tests for antibodies to thyroid peroxidase, a serum level greater than 10 IU/mL was considered a positive result. RESULTS: Subclinical hypothyroidism was present in 10.8% of participants and was associated with a greater age-adjusted prevalence of aortic atherosclerosis (odds ratio, 1.7 [95% CI, 1.1 to 2.6]) and myocardial infarction (odds ratio, 2.3 [CI, 1.3 to 4.0]). Additional adjustment for body mass index, total and high-density lipoprotein cholesterol level, blood pressure, and smoking status, as well as exclusion of women who took beta-blockers, did not affect these estimates. Associations were slightly stronger in women who had subclinical hypothyroidism and antibodies to thyroid peroxidase (odds ratio for aortic atherosclerosis, 1.9 [CI, 1.1 to 3.6]; odds ratio for myocardial infarction, 3.1 [CI, 1.5 to 6.3]). No association was found between thyroid autoimmunity itself an

How the Charge Can Affect the Formation of Gravastars

In recent work we physically interpreted a special gravastar solution characterized by a zero Schwarzschild mass. In fact, in that case, none gravastar was formed and the shell expanded, leaving behind a de Sitter or a Minkowski spacetime, or collapsed without forming an event horizon, originating what we called a massive non-gravitational object. This object has two components of non zero mass but the exterior spacetime is Minkowski or de Sitter. One of the component is a massive thin shell and the other one is de Sitter spacetime inside. The total mass of this object is zero Schwarzschild mass, which characterizes an exterior vacuum spacetime. Here, we extend this study to the case where we have a charged shell. Now, the exterior is a Reissner-Nordstr\"om spacetime and, depending on the parameter $\omega=1-\gamma$ of the equation of state of the shell, and the charge, a gravastar structure can be formed. We have found that the presence of the charge contributes to the stability of the gravastar, if the charge is greater than a critical value. Otherwise, a massive non-gravitational object is formed for small charges.Comment: 17 pages and 7 figures, several typos corrected, accepted for publication in JCA

Kijk op multifunctionele landbouw, omzet en impact : achtergronddocument

Het ministerie van LNV heeft een taskforce ingesteld die streeft naar een omzetverdubbeling van de multifunctionele landbouw (ook wel verbrede landbouw genoemd) in de periode 2008-2011. Voor het meten van de omzetontwikkeling heeft Wageningen UR een nulmeting over de situatie in 2007 verricht en geeft daarbij een uitgebreide onderbouwing van het aantal bedrijven, de omzet in de multifunctionele landbouw en haar impact op de maatschappij

Kijk op multifunctionele landbouw : omzet en impact

Inventarisatie van de omvang van de multifunctionele landbouw van 2007, uitgesplitst in de sectoren: zorgboerderijen, agrarische kinderopvang, boerderijverkoop, agrarische natuurbeheer, recreatie en toerisme en educati