New concepts for urban highways control

In recent decades a significant increase in traffic demand has occurred. This trend is especially present in dense populated areas where daily traffic congestions during rush hours occur regularly. Congestions are significant in road traffic where they can simultaneously reduce public transportation level of service (LoS) also. As consequence, even more people are using their car additionally increasing the congestion problem. Classic solution for solving the road traffic congestion problem is infrastructure build up. Today’s dense urban areas mostly do not allow this approach because of the lack of available building space. More advanced road traffic control solutions from the domain of intelligent transportation systems (ITS) are being more and more applied to optimally use the existing infrastructure (Papageorgiou et al., 2003.). Such solutions include coordination between several consecutive crossroads, dynamic traffic assignment, driver informing systems, etc. One of the ITS application areas is related to urban highways which present a class of highways used as a city bypass or are just passing a dense urban are. Their main characteristic is that they have a larger number of on- and off-ramps often placed at small distances. Due to the small distance, mutual on-ramp influence can occur enlarging the problems of daily congestions and associated decrease of highway LoS. In order to prevent the appearance of traffic standstill or to reduce its duration control approaches as ramp metering and variable speed limit control (VSLC) are being applied (Hegyi et al., 2010.). In recent years, new cooperative concepts between several on-ramps and VSLC are used as a combined urban highway control system (Ghods et al., 2007.). This paper presents a new learning based cooperative ramp metering strategy in which several well-known ramp metering strategies (ALIENA, SWARM, HERO) are used to create a learning set for an ANFIS (Gregurić et al., 2013.) based control structure. Optimal ramp metering values are obtained for a wide range of traffic demand on the urban highway and belonging on-ramps. Optimal ramp metering values for specific traffic demand characteristics obtained from most suitable ramp metering strategies are integrated into only one control strategy. Thus, the need of applying several ramp metering strategies and switching between them is avoided. Additionally, cooperation between VSLC and vehicle control by an on-board unit is described and a discussion about possible implementation is given. Proposed cooperative urban highway management approach is tested in simulations using the city of Zagreb bypass as case study. For simulation, the macroscopic highway traffic simulator CTMsim (Kurzhanskiy et al., 2008.) is used. Used CTMsim simulator augmented to enable simulation of VSLC and cooperative ramp metering approaches

Health and ill health of asylum seekers in Switzerland: an epidemiological study

Background: Although the focus of health care for people seeking asylum in Western European countries is usually on communicable diseases, there is little data about the general health care need of this population. In this study, we investigated the actual burden of disease among asylum seekers. Methods: Data were collected from a Swiss Health Maintenance Organisation (HMO; a type of managed care organization in which physicians act as gate keepers) that was set up specifically to provide health care for asylum seekers. The data included socio-demographic characteristics, international classification of diseases (ICD-10) diagnoses and number of clinic visits. Descriptive statistics were used to assess the types of health problems and the number of clinic visits. Logistic regression analysis was used to determine whether age, gender or country or region of origin was predictive in terms of incidence of disease as diagnosed by using ICD classifications. Results: The total number of asylum seekers (mean age 22 years; 38% women) enrolled in the HMO from 2000 through 2003 was 979. Half of this group came from the former country of Yugoslavia. The remainder came primarily from sub-Saharan Africa, Turkey, Iraq and Sri Lanka. The most common health problems encountered in the population included musculoskeletal diseases, respiratory diseases, depression and post-traumatic stress disorder. The prevalence of all disease clusters was significantly associated with age. One-fifth of the population did not request health care at all during the time they were enrolled in the HMO. It is not known whether those who did not visit the medical clinic did not require health care or just chose not to request clinic services. Conclusions: The most frequent health problems encountered in the study population were chronic medical conditions, not communicable acute diseases. Although health care services provided to asylum seekers usually focus on episodic acute care, what this group actually needs is continuity of car

First clinical judgment by primary care physicians distinguishes well between nonorganic and organic causes of abdominal or chest pain

Objective: To evaluate the accuracy of a preliminary diagnosis based solely on patient history and physical examination in medical outpatients with abdominal or chest pain. Design: Prospective observational study. Setting: General medical outpatient clinic in a university teaching hospital. Participants: One hundred ninety new, consecutive patients with a mean age of 44 years (SD=14 years, range 30-58 years) with a main complaint of abdominal or chest pain. Measurements and main results: The preliminary diagnosis, established on the basis of patient history and physical examination, was compared with a final diagnosis, obtained after workup at completion of the chart. A nonorganic cause was established in 66 (59%) of 112 patients with abdominal pain and in 65 (83%) of 78 with chest pain. The preliminary diagnosis of "nonorganic” versus "organic” causes was correct in 79% of patients with abdominal pain and in 88% of patients with chest pain. An "undoubted” preliminary diagnosis predicted a correct assessment in all patients with abdominal pain and in all but one patient with chest pain. Overall, only 4 patients (3%) were initially incorrectly diagnosed as having a nonorganic cause of pain rather than an organic cause. In addition, final nonorganic diagnosis (n=131) was compared with long-term follow-up by obtaining information from patients and, if necessary, from treating physicians. Follow-up information, obtained for 71% of these patients after a mean of 29 months (range 18-56 months) identified three other patients that had been misdiagnosed as having abdominal pain of nonorganic causes. Compared with follow-up, the diagnostic accuracy for nonorganic abdominal and chest pain at chart completion was 93% and 98%, respectively. Conclusions: A preliminary diagnosis of nonorganic versus organic abdominal or chest pain based on patient history and physical examination proved remarkably reliable. Accuracy was almost complete in patients with an "undoubted” preliminary diagnosis, suggesting that watchful waiting can be recommended in such case

blue-c Räumlich-immersive Projektions- und 3D Video-Portale für Telepräsenz. Teil 1: Konzept, Hardware und Videoverarbeitung

Zusammenfassung: Der folgende Beitrag beschreibt das Design und die Architektur von blue-c, einem Polyprojekt der ETH Zürich, an dem über einen Zeitraum von 4 Jahren bis zu 20 wissenschaftliche Mitarbeiter mitgewirkt haben und insgesamt 9 Doktorarbeiten entstanden sin

Comparative Performance of Different Statistical Models for Predicting Ground-Level Ozone (O3) and Fine Particulate Matter (PM2.5) Concentrations in Montréal, Canada

Ground-level ozone (O3) and fine particulate matter (PM2.5) are two air pollutants known to reduce visibility, to have damaging effects on building materials and adverse impacts on human health. O3 is the result of a series of complex chemical reactions between nitrogen oxides (NOx) and volatile organic compounds (VOCs) in the presence of solar radiation. PM is a class of airborne contaminants composed of sulphate, nitrate, ammonium, crustal components and trace amounts of microorganisms. PM2.5 is the respirable subgroup of PM having an aerodynamic diameter of less than 2.5 μm. Development of effective forecasting models for ground-level O3 and PM2.5 is important to warn the public about potentially harmful or unhealthy concentration levels. The objectives of this study is to investigate the applicability of Multiple Linear Regression (MLR), Principle Component Regression (PCR), Multivariate Adaptive Regression Splines (MARS), feed-forward Artificial Neural Networks (ANN) and hybrid Principal Component – Artificial Neural Networks (PC-ANN) models to predict concentrations of O3 and PM2.5 in Montréal (Canada). Air quality and meteorological data is obtained from the Réseau de surveillance de la qualité de l’air (RSQA) for the Airport Station (45°28′N, 73°44′W) and the Maisonneuve Station (45°30′N, 73°34′W) for the period January 2004 to December 2007. Air pollution data include concentration values for nitrogen monoxide (NO), nitrogen dioxide (NO2), carbon monoxide (CO) and 142 different volatile organic compounds. Meteorological data include solar irradiation (SR), temperature (Temp), pressure (Press), dew point (DP), precipitation (Precip), wind speed (WS) and wind direction (WD). Analysis of the available volatile organic compound data expressed on a propylene-equivalent concentration indicated that m/p-xylene, toluene, propylene and (1,2,4)-trimethylbenzene were species with the most significant ozone forming potential in the study area. Different models and architectures have been investigated through five case studies. Predictive performances of each model have been measured by means of performance metrics and forecast success rates. Overall, MARS models allowing second order interaction of independent basis functions yielded lower error, higher correlation and higher forecast success rates. This study indicates that models based on statistical methods can be cost-effective tools to forecast ground-level O3 and PM2.5 in Montréal and to provide support for decision makers in protecting human health

Sprouty2 expression controls endothelial monolayer integrity and quiescence

Vascular integrity is fundamental to the formation of mature blood vessels and depends on a functional, quiescent endothelial monolayer. However, how endothelial cells enter and maintain quiescence in the presence of angiogenic factors is still poorly understood. Here we identify the fibroblast growth factor (FGF) antagonist Sprouty2 (Spry2) as a key player in mediating endothelial quiescence and barrier integrity in mouse aortic endothelial cells (MAECs): Spry2 knockout MAECs show spindle-like shapes and are incapable of forming a functional, impermeable endothelial monolayer in the presence of FGF2. Whereas dense wild type cells exhibit contact inhibition and stop to proliferate, Spry2 knockout MAECs remain responsive to FGF2 and continue to proliferate even at high cell densities. Importantly, the anti-proliferative effect of Spry2 is absent in sparsely plated cells. This cell density-dependent Spry2 function correlates with highly increased Spry2 expression in confluent wild type MAECs. Spry2 protein expression is barely detectable in single cells but steadily increases in cells growing to high cell densities, with hypoxia being one contributing factor. At confluence, Spry2 expression correlates with intact cell-cell contacts, whereas disruption of cell-cell contacts by EGTA, TNFα and thrombin decreases Spry2 protein expression. In confluent cells, high Spry2 levels correlate with decreased extracellular signal-regulated kinase 1/2 (Erk1/2) phosphorylation. In contrast, dense Spry2 knockout MAECs exhibit enhanced signaling by Erk1/2. Moreover, inhibiting Erk1/2 activity in Spry2 knockout cells restores wild type cobblestone monolayer morphology. This study thus reveals a novel Spry2 function, which mediates endothelial contact inhibition and barrier integrit

Atomic-scale grain boundary engineering to overcome hot-cracking in additively-manufactured superalloys

There are still debates regarding the mechanisms that lead to hot cracking in parts build by additive manufacturing (AM) of non-weldable Ni-based superalloys. This lack of in-depth understanding of the root causes of hot cracking is an impediment to designing engineering parts for safety-critical applications. Here, we deploy a near-atomic-scale approach to investigate the details of the compositional decoration of grain boundaries in the coarse-grained, columnar microstructure in parts built from a non-weldable Ni-based superalloy by selective electron-beam melting. The progressive enrichment in Cr, Mo and B at grain boundaries over the course of the AM-typical successive solidification and remelting events, accompanied by solid-state diffusion, causes grain boundary segregation induced liquation. This observation is consistent with thermodynamic calculations. We demonstrate that by adjusting build parameters to obtain a fine-grained equiaxed or a columnar microstructure with grain width smaller than 100 $\mu$m enables to avoid cracking, despite strong grain boundary segregation. We find that the spread of critical solutes to a higher total interfacial area, combined with lower thermal stresses, helps to suppress interfacial liquation.Comment: Accepted version at Acta Materiali

Well informed farmers and consumers are positive about GM crops in Europe and Africa

Genetically modified (GM) crops are cultivated globally on more than 185 million hectares, but the use of GM crops in Europe and Africa is very limited. Politicians are reluctant to allow such crops because they fear negative public reaction. The political hostility in the EU towards GM crops also has a significant impact on how African policy makers form their opinions for accepting GM crops in their own countries. However, studies reveal that specific types of GM food are welcomed by consumers and that few Europeans avoid GM labels when buying food. Similarly, African farmers and consumers are generally positive about GM crops. Policy makers should take these results into account when a decision needs to be made on whether or not to allow GM crop cultivation in their country