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To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.jue.2007.01.001 Byline: B. De Borger (a), F. Dunkerley (b), S. Proost (b)(c) Keywords: Congestion pricing; Transport investment; Transit traffic Abstract: This paper studies pricing and investment decisions on a congested transport corridor where the elements of the corridor are controlled by different governments. A corridor can be an interstate highway or railway line, or an inter-modal connection. We model the simplest corridor: two transport links in series, where each of the links is controlled by a different government. Each link is used by transit as well as by local traffic; both links are subject to congestion. We consider a two-stage non-cooperative game where both governments strategically set capacity in the first stage and play a pricing game in the second stage. Three pricing regimes are distinguished: (i) differentiated tolls between local and transit transport, (ii) one uniform toll on local and transit traffic, and (iii) only the local users can be tolled. Numerical analysis illustrates all theoretical insights. A number of interesting results are obtained. First, transit tolls on the network will be inefficiently high. If only local traffic can be tolled, however, the Nash equilibrium tolls are inefficiently low. Second, raising the toll on transit through a given country by one euro raises the toll on the whole trajectory by less than one euro. Third, higher capacity investment in a given region not only reduces optimal tolls in this region under all pricing regimes but it also increases the transit tolls on the other link of the corridor. Fourth, capacities in the different regions are strategic complements: when one country on the corridor increases transport capacity, it forces the other country to do the same. Finally, if transit is sufficiently important, it may be welfare improving not to allow any tolling at all, or to only allow the tolling of locals. If countries can toll transit, capacity and toll competition would lead to insufficient investment and strong tax exporting behavior, so that welfare is actually higher in the absence of any tolling at all. Author Affiliation: (a) Department of Economics, University of Antwerp, Prinsstraat 13, B-2000 Antwerp, Belgium (b) Department of Economics, Catholic University of Leuven, Naamsestraat 69, B-3000 Leuven, Belgium (c) CORE, 1348, Louvain-La-Neuve, Belgium Article History: Received 30 March 2006; Revised 16 January 2007

The purpose of this paper is to study the effects of tolling road use on a parallel road network where each link can be tolled by a different government. Using both theoretical and numerical models, the paper analyses the potential tax competition between countries that each maximise the surplus of local users plus tax revenues in controlling local and transit transport. Three types of tolling systems are considered: (i) toll discrimination between local traffic and transit, (ii) only uniform tolls on local and transit transport are acceptable, (iii) tolls on local users only. The results suggest that the welfare effects of introducing transit tolls are large, but that differentiation of tolls between local and transit transport as compared to uniform tolls does not yield large welfare differences. Also, the welfare effects of toll cooperation between countries are relatively small in comparison with the welfare gains of non-cooperative tolling of transit. The numerical model further illustrates the effects of different transit shares and explicitly considers the role of asymmetries between countries. Higher transit shares strongly raise the transit toll and slightly decrease local tolls. With asymmetric demands, the welfare gains of introducing differentiated tolling rise strongly for the country with lower local demand. JEL classification: H23; H71; R41; R48 Keywords. Congestion pricing; Transit traffic

To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.euroecorev.2004.06.005 Byline: B. De Borger (a), S. Proost (b), K. Van Dender (c) Abstract: The purpose of this paper is to study the effects of tolling road use on a parallel road network where each link can be tolled by a different government. Using both theoretical and numerical models, the paper analyses the potential tax competition between countries that each maximise the surplus of local users plus tax revenues in controlling local and transit transport. Three types of tolling systems are considered: (i) toll discrimination between local traffic and transit, (ii) only uniform tolls on local and transit transport are acceptable, (iii) tolls on local users only. The results suggest that the welfare effects of introducing transit tolls are large, but that differentiation of tolls between local and transit transport as compared to uniform tolls does not yield large welfare differences. Also, the welfare effects of toll cooperation between countries are relatively small in comparison with the welfare gains of non-cooperative tolling of transit. The numerical model further illustrates the effects of different transit shares and explicitly considers the role of asymmetries between countries. Higher transit shares strongly raise the transit toll and slightly decrease local tolls. With asymmetric demands, the welfare gains of introducing differentiated tolling rise strongly for the country with lower local demand. Author Affiliation: (a) Department of Economics, University of Antwerp, Prinsstraat 13, B-2000 Antwerp, Belgium (b) Department of Economics, Catholic University of Leuven, Naamsestraat 69, B-3000 Leuven, Belgium (c) Department of Economics, University of California at Irvine, Irvine, CA 92697-5100, USA Article History: Received 8 September 2003; Accepted 23 June 2004

Abstract Background Large-scale identification of the interrelationships between different components of the cell, such as the interactions between proteins, has recently gained great interest. However, unraveling large-scale protein-protein interaction maps is laborious and expensive. Moreover, assessing the reliability of the interactions can be cumbersome. Results In this study, we have developed a computational method that exploits the existing knowledge on protein-protein interactions in diverse species through orthologous relations on the one hand, and functional association data on the other hand to predict and filter protein-protein interactions in Arabidopsis thaliana. A highly reliable set of protein-protein interactions is predicted through this integrative approach making use of existing protein-protein interaction data from yeast, human, C. elegans and D. melanogaster. Localization, biological process, and co-expression data are used as powerful indicators for protein-protein interactions. The functional repertoire of the identified interactome reveals interactions between proteins functioning in well-conserved as well as plant-specific biological processes. We observe that although common mechanisms (e.g. actin polymerization) and components (e.g. ARPs, actin-related proteins) exist between different lineages, they are active in specific processes such as growth, cancer metastasis and trichome development in yeast, human and Arabidopsis, respectively. Conclusion We conclude that the integration of orthology with functional association data is adequate to predict protein-protein interactions. Through this approach, a high number of novel protein-protein interactions with diverse biological roles is discovered. Overall, we have predicted a reliable set of protein-protein interactions suitable for further computational as well as experimental analyses.

This paper discusses the effects of alternative ways of using external cost estimates to regulate investments and generation in the electricity production sector. Starting from the existing system, four alternatives are considered: emission taxes for the utility and for independent producers, emission taxes limited to the electric utility, emission permits limited to the electric utility and finally a system where only investments are regulated, and dispatch is not. Taking external damage estimates from the literature, these alternatives are compared using a dynamic partial equilibrium model of the Belgian electricity market for the period 1995-2034. The efficiency and distribution effects of the alternative environmental policy instruments are quantified. [ABSTRACT FROM AUTHOR]

Background: Human immunodeficiency virus (HIV) and iron deficiency (ID) affect many African children. Both HIV and iron status interact with gut microbiota composition and related biomarkers. The study's aim was to determine the associations of HIV and iron status with gut microbiota composition, gut inflammation and gut integrity in South African school-age children., Methods: In this two-way factorial case-control study, 8- to 13-year-old children were enrolled into four groups based on their HIV and iron status: (1) With HIV (HIV+) and ID (n = 43), (2) HIV+ and iron-sufficient nonanaemic (n = 41), (3) without HIV (HIV-) and ID (n = 44) and (4) HIV- and iron-sufficient nonanaemic (n = 38). HIV+ children were virally suppressed (<50 HIV RNA copies/ml) on antiretroviral therapy (ART). Microbial composition of faecal samples (16S rRNA sequencing) and markers of gut inflammation (faecal calprotectin) and gut integrity (plasma intestinal fatty acid-binding protein [I-FABP]) were assessed., Results: Faecal calprotectin was higher in ID versus iron-sufficient nonanaemic children (p = 0.007). I-FABP did not significantly differ by HIV or iron status. ART-treated HIV (redundancy analysis [RDA] R 2  = 0.009, p = 0.029) and age (RDA R 2  = 0.013 p = 0.004) explained the variance in the gut microbiota across the four groups. Probabilistic models showed that the relative abundance of the butyrate-producing genera Anaerostipes and Anaerotruncus was lower in ID versus iron-sufficient children. Fusicatenibacter was lower in HIV+ and in ID children versus their respective counterparts. The prevalence of the inflammation-associated genus Megamonas was 42% higher in children with both HIV and ID versus HIV- and iron-sufficient nonanaemic counterparts., Conclusions: In our sample of 8- to 13-year-old virally suppressed HIV+ and HIV- children with or without ID, ID was associated with increased gut inflammation and changes in the relative abundance of specific microbiota. Moreover, in HIV+ children, ID had a cumulative effect that further shifted the gut microbiota to an unfavourable composition., (© 2023 The Authors. Journal of Human Nutrition and Dietetics published by John Wiley & Sons Ltd on behalf of British Dietetic Association.)

To examine the prevalence of 12-month mood disorders and receipt of mental health treatment among a volunteer sample of higher education students during the 2nd and 3rd COVID-19 wave in the Flanders region. Web-based self-report surveys were obtained from 9101 students in higher education in the Flemish College Surveys (FLeCS) in Flanders, Belgium. As part of the World Health Organization's World Mental Health-International College Student Initiative, we screened for 12-month mood disorders (major depressive episode (MDE), mania/hypomania), and service use. We used poststratification weights to generate population-representative data on key socio-demographic characteristics. 50.6% of the respondents screened positive for 12-month mood disorders (46.8% MDE, of which 22.9% with very severe impact). Use of services was very low, with estimates of 35.4% for MDE, 31.7% for mania, and 25.5% for hypomania. Even among students with very severe disorders, treatment rates were never higher than 48.3%. Most common barriers for not using services were: the preference to handle the problem alone (83.4%) and not knowing where to seek professional help (79.8%). We found a high unmet need for mood problems among college students; though caution is needed in interpreting these findings given the volunteer nature of the sample. A reallocation of treatment resources for higher education students should be considered, particulary services that focus on innovative, low-threshold, and scalable interventions., Competing Interests: Declaration of competing interest In the past 3 years, Dr. Kessler was a consultant for Datastat, Inc., Holmusk, RallyPoint Networks, Inc., and Sage Therapeutics. He has stock options in Mirah, PYM, and Roga Sciences., (Copyright © 2023. Published by Elsevier Ltd.)

Extensive scientific and clinical microbiome studies have explored contemporary variation and dynamics of the gut microbiome in human health and disease 1-3 , yet the role of long-term life history effects has been underinvestigated. Here, we analyzed the current, quantitative microbiome composition in the older adult Bruneck Study cohort (Italians, Bruneck, n = 304 (male, 154; female, 150); age 65-98 years) with extensive clinical, demographic, lifestyle and nutritional data collected over the past 26 years 4 . Multivariate analysis of historical variables indicated that medication history, historical physical activity, past dietary habits and specific past laboratory blood parameters explain a significant fraction of current quantitative microbiome variation in older adults, enlarging the explanatory power of contemporary covariates by 33.4%. Prediction of current enterotype by a combination of past and contemporary host variables revealed good levels of predictability (area under the curve (AUC), 0.78-0.83), with Prevotella and dysbiotic Bacteroides 2 being the best predicted enterotypes. These findings demonstrate long-term life history effects on the microbiota and provide insights into lifestyle variables and their role in maintaining a healthy gut microbiota in later life., (© 2022. The Author(s).)

Covid-19 has important implications for public transport operations. Increased teleworking and the perceived infection risk on public transport vehicles have drastically reduced demand in many cities. At the same time, physical distancing has effectively reduced available peak-period public transport capacity. In this paper, we use a simple model to study the effect of these changes on second-best optimal pricing and frequency provision, assuming that car use is underpriced. A numerical application reflecting the public transport situation in Brussel is provided. Results include the following. First, more telework and the increased perceived infection risk have opposite effects on the fare, so that it may be optimal not to change the fare at all. Optimal frequency is likely to decline. Second, holding the fare and frequency constant at their pre-Covid second-best optimal values, more telework reduces the public transport deficit if car use is underpriced. Third, extending the model to allow for passengers with different vulnerability towards Covid-19, allowing fare and frequency differentiation implies that vulnerable users will face higher fares only if their risk perception is sufficiently higher than that of the non-vulnerable, and car use is not too much underpriced. Occupancy rates will be lower for the vulnerable passengers. Fourth, the numerical results for Brussels show that telework and a high perceived infection risk for workers may yield a welfare optimum whereby commuters do almost not use public transport. Offering a low frequency suffices to deal with the captive demand by school children and students. Lastly, reserved capacity for the vulnerable users and stimuli for walking and biking to school may be useful policies to deal with the crowding risk., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2022 Elsevier Ltd. All rights reserved.)

During the maturation phase of flower development, the onset of anthesis visibly marks the transition from buds to open flowers, during which petals stretch out, nectar secretion commences, and pollination occurs. Analysis of the metabolic changes occurring during this developmental transition has primarily focused on specific classes of metabolites, such as pigments and scent emission, and far less on the whole network of primary and secondary metabolites. To investigate the metabolic changes occurring at anthesis, we performed multi-platform metabolomics alongside RNA sequencing in individual florets harvested from the main inflorescence of Arabidopsis (Arabidopsis thaliana) ecotype Col-0. To trace metabolic fluxes at the level of the whole inflorescence and individual florets, we further integrated these studies with radiolabeled experiments. These extensive analyses revealed high-energy-level metabolism and transport of carbohydrates and amino acids, supporting intense metabolic rearrangements occurring at the time of this floral transition. These comprehensive data are discussed in the context of our current understanding of the metabolic shifts underlying flower opening. We envision that this analysis will facilitate the introgression of floral metabolic traits promoting pollination in crop species for which a comprehensive knowledge of flower metabolism is still limited., (© The Author(s) 2022. Published by Oxford University Press on behalf of American Society of Plant Biologists.)

Purpose: Both HIV and oral iron interventions may alter gut microbiota composition and increase gut inflammation. We determined the effect of oral iron supplementation on gut microbiota composition, gut inflammation, and iron status in iron-depleted South Africa school-aged children living with HIV (HIV+) but virally suppressed on antiretroviral therapy and children without HIV (HIV-ve)., Methods: In this before-after intervention study with case-control comparisons, we provided 55 mg elemental iron from ferrous sulphate, once daily for 3 months, to 33 virally suppressed (< 50 HIV RNA copies/mL) HIV+ and 31 HIV-ve children. At baseline and endpoint, we assessed microbial composition of faecal samples (16S rRNA sequencing), and markers of gut inflammation (faecal calprotectin), anaemia (haemoglobin) and iron status (plasma ferritin, soluble transferrin receptor). This study was nested within a larger trial registered at clinicaltrials.gov as NCT03572010., Results: HIV+ (11.3y SD ± 1.8, 46% male) and HIV-ve (11.1y SD ± 1.7, 52% male) groups did not significantly differ in age or sex ratio. Following iron supplementation, improvements were observed in haemoglobin (HIV+ : 118 to 124 g/L, P = 0.003; HIV-ve: 120 to 124 g/L, P = 0.003), plasma ferritin (HIV+ : 15 to 34 µg/L, P < 0.001; HIV-ve: 18 to 37 µg/L, P < 0.001), and soluble transferrin receptor (HIV+ : 7.1 to 5.9 mg/L, P < 0.001; HIV-ve: 6.6 to 5.7 mg/L, P < 0.001), with no significant change in the relative abundance of any genera, alpha diversity of the gut microbiota (HIV+ : P = 0.37; HIV-ve: P = 0.77), or faecal calprotectin (HIV+ : P = 0.42; HIV-ve: P = 0.80)., Conclusion: Our findings suggest that oral iron supplementation can significantly improve haemoglobin and iron status without increasing pathogenic gut microbial taxa or gut inflammation in iron-depleted virally suppressed HIV+ and HIV-ve school-age children., (© 2022. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany.)