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Background: Cognitive impairment (CI) is common in Multiple Sclerosis (MS), and its prevalence rate ranges between 22% and 70%. Because CI significantly impacts vocational status, caregiver burden, and quality of life, an accurate neuropsychological assessment is required. Three widely used and validated batteries for MS-associated CI are the Brief Repeatable Neuropsychological Battery (BRN-B), the Minimal Assessment of Cognitive Function (MACFIMS), and the Brief International Cognitive Assessment (BICAMS). Although similar, these batteries differ in time-consuming and in specific tests employed. This study aims to assess the sensitivity of cognitive tests included in these batteries through an Item Response Theory approach. Methods: Ninety-seven patients with MS and 91 demographically matched controls (HC) were consecutively assessed using the three neuropsychological batteries (i.e., BRN-B, MACFIMS, and BICAMS). Continuous Response Model (CRM) was used to identify the cognitive test(s) that best discriminate patients with MS from HC. Receiver Operating Characteristic (ROC) curve analysis was used to determine the accuracy of the CRM results. Results: Cognitive tests loaded on two different latent variables: the 'higher-order executive functioning,' consisting of tests assessing concept formation, problem-solving, and inhibitory control, and the 'memory and information processing speed,' comprising tests assessing long-term, working memory, and information processing speed. The Delis Kaplan Executive Functioning System-Sorting Test and the Stroop Test were the most sensitive tests in differentiating cognitive functioning between MS and HC. Conclusions: This study confirms the importance of including a more extensive executive assessment in MS clinical practice since higher-order executive functions (e.g., abstraction and inhibitory control) significantly impact patients' quality of life and functional autonomy. Clinical implications of careful dissection of executive functioning in MS neuropsychological assessment are discussed.

The application of zinc layer anode to reinforced concrete structure has been well known for many years. This galvanic cathodic protection system was specified being a corrosion control system for general steel in concrete as well as civil structures. A good way to determine the dimensioning elements of the galvanic protection system, is to carry out a pilot test being monitored in situ, and exposed under on site conditions including local concrete remediation or repair works. This paper presents an analysis of the current distribution and steel polarization data that have been collected from a car park project in the French Alps.

Der Zweck der im vorliegenden Beitrag beschriebenen Untersuchung bestand darin, die Betonstahlbewehrung und nach Moglichkeit auch die Spannglieder auf einer Flache von insgesamt 8 000 m2 der oberen Bruckenfahrbahn des Viadukts “Viadotto Colle Isarco” an der Brennerautobahn mittels Potentialfeldmessungen auf Korrosionserscheinungen zu untersuchen. So wurden Zonen mit hoher Korrosionswahrscheinlichkeit ermittelt und anschliesend durch Offnen und Sandstrahlen inspiziert. Auf der Grundlage dieser Prufungen konnte abgeschatzt werden, dass auf etwa 9 % der Gesamtflache eine hohe Korrosionswahrscheinlichkeit in den Spanngliedern gegeben ist. Bei fruheren Inspektionen sind bereits gebrochene Spannglieder festgestellt worden. Samtliche Bruche wurden dabei im Gewindebereich der Verbindungsgelenke festgestellt. In den korrodierten Spanngliedern, die in den “aktiven” Zonen abseits der Verbindungsgelenke lagen, wurden dagegen keine Bruche gefunden. Von den gebrochenen Spanngliedern wurden Proben genommen und zur metallurgischen Analyse ins Labor geschickt. Dabei wurden keine Anzeichen fur eine Wasserstoffversprodung des verwendeten Stahls festgestellt. Die Bruche, die in den Spanngliedern bei fruheren Inspektionen festgestellt worden sind, wurden hochstwahrscheinlich durch Zyklen mit hoherer Belastungsermudung durch Verkehrslasten in Kombination mit Korrosion aufgrund belastungsempfindlicher Verbindungsgelenke verursacht. Corrosion survey of the bridge deck “Viadotto Colle Isarco”/“Autobahnbrucke Gossensas” on the Motorway called “Autostrada del Brennero” in North-Italy The scope of this corrosion survey was to detect and quantify zones with high corrosion probability of the normal reinforcement and if possible the prestressed tendons of a total of 8 000 m2 surface area of the upper bridge deck of the “Viadotto Colle Isarco”. This viaduct is part of the A22 Motorway called “Autostrada del Brennero” and lays 10 km's south of the Austrian-Italian border in Italian territory approximately 1 200 m high in the Alps. In case serious problems were found no recommendations were requested at this point of the survey due to the size and the structural complexity of the concrete structure. Zones with high probability of corrosion were identified by the potentials measured and inspected through scarification and sandblasting. Based on this verification it was estimated an approximate 9 % of the total surface area with high probability of corrosion in the prestressed tendons. This amount is based on adding up all measuring points with a potential being more negative than –450 mV divided by the total amount of measuring points. During previous inspections fractured prestressed tendons were found. All the fractures were found in the threaded region of the coupler joints but no fractures were found in corroded tendons laying in the “active” zones away from the coupler joints. Samples taken from the fractured tendons were sent to the lab for metallurgical analysis and revealed no susceptibility for hydrogen embrittlement of the steel used which has a perlitic microstructure. Fractures found in the tendons in previous inspections are most probably caused by major stress fatigue cycles from traffic loads in combination with corrosion due to the stress-sensitive couplings. Exactly similar cases (Heerdter crossing in Dusseldorf in 1976) were found in old reports, e.g. published in the technical report 26 “Influence of material and processing on Stress Corrosion Cracking of prestressing steel – case studies” by the International Federation for Structural Concrete (fib) in Lausanne.

This paper gives insight in the research and investigations which were undertaken on a post tensioned light-weight concrete box girder bridge in the Netherlands. This project started in the first half of 2013 and measurements are still executed regularly. Due to long-term leakage of a longitudinal joint between 2 parts of the bridge, chlorides had penetrated into the concrete up to the level of the reinforcement and beyond, causing severe corrosion of the steel, spalling of the concrete cover and eventually causing danger for the shipping underneath the bridge due to falling lumps of concrete. To solve this problem, Galvanic Cathodic Protection (GCP) was applied in 2 stages. Firstly, in 2013, zinc based anode strips were applied on the soffit of 2 post tensioned lightweight bridge segments for the purpose of testing and monitoring. After obtaining good results from the test, in 2014/2015 the remaining 29 bridge segments were repaired and protected with the same GCP system as well. This paper reviews subsequent potential decay and current densities measurements, which have provided valuable information on GCP performance and throwing power. The results of anode performance at different locations and depths are reviewed. Concrete resistivity have shown a major influence on the effectiveness of the installed GCP system.