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For more than six years, the automated ultrasonic and eddy current systems for the inspection of railroad wheel sets developed by Fraunhofer IZFP and Fraunhofer TEG have been field-hardened through daily operation at various maintenance facilities of the Deutsche Bahn (DB). The testing stations are equipped with IZFP’s multi-channel electronics, a modular PC integrated system operating inside 19″ rack-mounted industrial computers. Special requirements for new installations of stationary systems (AURA) and underfloor testing stations (UFPE) called for the development of state-of-the-art miniaturised front-end ultrasonic and eddy current test instrumentation. This innovation offers new dimensions for the concept and design of such systems, including features providing effortless maintenance of the inspection systems. Due to the small size of the electronic modules they can be placed in close proximity to the transducer assembly. High-speed networking techniques ensure the transfer of all the acquired digital ultrasonic and eddy current data from the front-end modules to the workstation responsible for data acquisition and analysis. The new front-end technology is applied for the testing stations of the latest generation. One example is a system installed at the DB plant, Krefeld, specifically designed for the ultrasonic testing of Inter-City Express (ICE) train drive wheels. The transducer assembly for wheel rim and disk inspection includes hot-swap modules with integrated UT front-end modules adapted to inspect specific wheel disk configurations. A second example represents testing equipment operating at the Süddeutsche Rail Service GmbH, Kaiserslautern. Ultrasonic and eddy current front-end modules are responsible for the inspection of the wheel rim of disassembled wheel sets of freight cars. In addition to the wheel rim, the solid axle is inspected in the same test stand using GE’s phased array system. Miniaturised front-end modules are also advantageous for the inspection with the wheel sets installed at the train. The concept of such an underfloor testing system is outlined. [ABSTRACT FROM AUTHOR]

Previous standards for the manufacturing inspection of railroad wheels using ultrasound, such as UIC 812, have been replaced by new standards, for example EN 13262 and RD32.144-2000, both requiring ultrasonic testing by means of the immersion technique. These new standards require the development of an ultrasonic technique for 100% coverage of the wheel rim and wheel hub, and in special cases for both straight and curved wheel disks. In order to encompass a large variety of railroad wheel designs, inspection and handling techniques should be capable of dealing with wheel diameters ranging from 600 mm to 1300 mm (23″ to 51″) at testing cycles from 1 to 4 minutes per wheel. The current requirement for the minimum detectable flaw size is DSR 1 mm (disc shape reflector, DSR, 1 mm diameter) for high-speed train wheels rims and DSR 2 mm for all other wheel rims. The minimum detectable flaw size for all other wheel areas (hub and disk areas) is DSR 3 mm. To meet all these criteria, a Rail Wheel Inspection (RWI) system was developed by IZFP and its partners. The system consists of an ultrasonic testing sub-system, immersion tank and transportation/handling sub-systems. Test cycles of 1 minute per wheel require two immersion tanks and two transportation/handling sub-systems. The ultrasonic sub-system features modular computer-aided 6 to 16-channel UT electronics (PCUS 11) to employ 6 to 16 ultrasonic transducers (the precise number is determined by the testing procedure). This paper offers descriptions of, and results from, three of these systems that have been integrated into manufacturing processes at German and Russian wheel manufacturers, and provides details on the following topics: □ Wheel rim inspection, single-tank immersion technique, 4 minute inspection cycle per wheel (Bochum, Germany) □ Wheel rim, hub and disc inspection, single-tank immersion technique, 2 minute inspection cycle per wheel (Ilsenburg, Germany) □ Wheel rim, hub and disc inspection, dual-tank immersion technique, 1 minute inspection cycle per wheel (Nishny-Tagil, Russia) [ABSTRACT FROM AUTHOR]

• Early neglect is associated with attenuated hair cortisol concentration (HCC). • The neglect-related attenuation of HCC differentiate between patients and controls. • Early neglect interacts with attenuated HCC in sensitizing for symptoms of PTSD. Childhood adversities and traumatic events have each been associated with hypothalamus-pituitary-adrenal (HPA) axis dysregulation and trauma-related symptoms in adulthood. Hair cortisol concentration (HCC) reflects cumulative cortisol levels over the course of months and is discussed as a potential marker between trauma-induced neuroendocrine dysfunction and trauma-related symptoms. The present study examines this hypothetical link by delineating the impact of exposure to categories of abuse and neglect during development and lifetime traumatic experiences on HCC and trauma-related symptoms. The Maltreatment and Abuse Chronology Exposure (MACE) scale, Life Events Checklist, and predictive analytics were used to evaluate the importance of type and timing of maltreatment and trauma load on HCC in inpatients (n = 183) with different psychiatric diagnoses. Additionally, a comparison group of n = 75 controls were recruited from the community. The extent to which the relationship between trauma load and trauma-related symptoms was influenced by childhood adversities and HCC was determined by analysis of variance. Early neglect, in particular neglect at 3 years, emerged as the most important predictor of adult HCC. Post-hoc explanatory analysis showed that patients with high neglect at age 3 had lower HCC compared to patients with low neglect at age 3 and controls. Patients with high neglect at age 3 and low cortisol reported increased trauma-related symptoms upon trauma exposure. Results strengthen evidence that inadequate care and neglect during critical periods alter HPA axis biology towards enduring reduction in cortisol, the latter being associated with augmented trauma-related symptoms upon trauma exposure. If validated by longitudinal assessments these cross-sectional findings suggest biological mechanisms of childhood adversities into psychopathology in adulthood. [ABSTRACT FROM AUTHOR]

Slow cortical potentials, response speed, and peripheral physiological responses were investigated in two experiments with four groups of male subjects. Experiment 1 examined constant foreperiod reaction time in a sound light button press sequence with an interstimulus interval of 2 sec. Experiment 2 investigated constant foreperiod reaction time conditions with a sudden change from controllable to uncontrollable offset of an aversive imperative stimulus. There were two visual warning stimuli of 6-sec duration followed by an aversive or neutral imperative stimulus to be terminated by button press within I sec. Forty trials of this contingency were followed by 40 trials with 5-sec duration of imperative stimuli irrespective of response speed. Subjects were selected by high or low scores on two questionnaire scales measuring physical anhedonia (PA) and body image distortion (BI). In the first paradigm subjects with high PA scores as compared to low-scoring subjects showed less resolution of left precentral CNV after S2, i.e., a more pronounced post-imperative negative component. In the second paradigm a postimperative negative variation (PINV) developed in all groups, but was more pronounced in frontal recordings and in subjects with high PA and BI scores. Results are discussed in the context of electrocortical phenomena observed in psychopathological groups. [ABSTRACT FROM AUTHOR]

Objectives When motor imagery ( MI) is impaired in stroke patients, it is not clear, whether this is caused by the central lesion with a disruption of networks or this may be due to inactivity/lack of practice following hemiparesis. To answer this question, we investigated MI in two groups of patients: stroke patients and patients with no central lesion, who suffered high-grade tetraparesis caused by myopathy or spinal muscular atrophy. Materials and methods The first study measured MI in 31 sub-acute and chronic stroke patients with hand paresis. We used self-assessment questionnaires [ Kinaesthetic and Visual Imagery Questionnaire ( KVIQ), the Vividness of Motor Imagery Questionnaire ( VMIQ)] as well as a new chronometric test (mental version and normal/physical version of Box and Block Test). The second study assessed MI in 10 patients without a central lesion, but with severe tetraparesis of peripheral origin. They were incapable of performing the requested task physically. Results MI in patients was better (i) for the third-person ( VMIQ3.P) compared to the first-person perspective ( VMIQ1.P), (ii) in patients without sensory impairment compared to those with impaired proprioception, (iii) in patients with light paresis compared to severe paresis and (iv) for the non-affected than the affected hand ( KVIQ-10). Patients with severe tetraparesis were able to imagine another person's knee bends, but were not capable of imagining themselves performing knee bends. Conclusions MI may be hampered on the affected side in severely paretic patients, particularly in the presence of impaired proprioception. Remarkably, the second study illustrates that motor experiences shape MI. This confirms the close relationship between MI and movement execution. The study advocates the careful use of test batteries for assessment of MI when investigating mental training in clinical trials. Not all patients might benefit to the same extent from MI training. This is possibly contingent on intact proprioception and preserved MI. [ABSTRACT FROM AUTHOR]

The chewing of the khat leaves, which contain the amphetamine-like cathinone, is a traditional habit in Somalia. Our objective was to explore the effects of khat use and Posttraumatic Stress Disorder (PTSD) on paranoid symptoms and to test a potential causal chain. We report on a cross-sectional study in Somalia that was conducted in 2003. Trained local staff interviewed 8723 personnel of armed groups in seven regional convenience samples. Of them, 8124 were included in the analysis. We assessed current khat use, PTSD symptoms, functional drug use and paranoid ideation using items from the Composite International Diagnostic Interview (CIDI) and the Somali version of the Posttraumatic Stress Diagnostic Scale (PDS). Applying the causal steps approach, in a series of logistic regression models, we used PTSD as independent and paranoia as outcome variable; the quantity of khat use was defined as mediator variable and functional drug use as moderator. The results showed that respondents with PTSD used khat more frequently. Khat chewers with PTSD reported a higher intake compared to khat chewers without PTSD. Among excessive khat chewers with PTSD, paranoia was most frequent. The greatest amount of khat use was among respondents with PTSD who indicated that they found drugs help them to forget war experiences. The proposed mediated moderation model was supported by the data, i.e. besides the direct effects of PTSD and functional drug use on paranoia, the amount of khat use appeared to be a mechanism, by which paranoia is caused. We conclude that in our data we have uncovered a relationship between khat, PTSD and paranoia. Khat is functionally used by respondents with PTSD. Findings support a dose effect: the more khat consumption and when a respondent has PTSD, the higher the odds for paranoid ideation. However, the proposed causal chain needs to be confirmed in longitudinal studies. Demobilization and reintegration programs in Somalia need to be prepared to deal with complex psychological problems. [ABSTRACT FROM AUTHOR]

Abstract: Knowledge about the recovery of language functions in bilingual aphasic patients who suffer from left-hemispheric stroke is scarce. Here, we present the case of an early bilingual patient (German/French) with chronic aphasia. Functional magnetic resonance imaging (fMRI) was used to investigate neural correlates of language performance during an overt picture naming task in German and French (a) 32 months after stroke to assess differential recovery of both languages as a function of the preceding language therapy that was provided exclusively in German and (b) after additional short-term intensive (German) language training. At the first investigation behavioral performance confirmed selective recovery of German naming ability which was associated with increased functional brain activation compared to the French naming condition. Changes in behavioral performance and brain activation pattern as disclosed by fMRI after an additional experimental treatment were confined to the trained (German) language and indicate bilateral neuroplastic reorganization. No generalization to the untrained (French) language was observed. The present case results demonstrate use and/or training-dependent differential recovery of expressive language functions and an enhanced pattern of brain activation as a function of the rehabilitation efforts that were focussed exclusively on the patient''s German language abilities. [Copyright &y& Elsevier]

Psychotherapie verändert klinische Symptome und mentale Funktionen und damit auch Leistungen des Gehirns. Dies bedeutet, dass sich die Architektur des Gehirns durch erfolgreiche therapeutische Intervention modifizieren lässt. Tatsächlich kann der Nachweis sogar auf makroskopischer Ebene gelingen, wie wir hier am Beispiel der Behandlung seelischer Erkrankungen in Folge von traumatischem Stress darlegen. Die Narrative Expositionstherapie (NET) wurde dabei mit Standardbehandlungen (TU; treatment as usual) bei traumatisierten Asylsuchenden in Deutschland verglichen. Der Erfolg der NET spiegelte sich nicht nur in den Symptomkennwerten wider, sondern auch in neuromagnetischen Messungen. Diese zeigten in der 6-Monats-Katamnese, dass sich die Hirnaktivität in der NET-Gruppe an diejenige einer psychisch unauffälligen Normstichprobe angenähert hatte. In der TU-Gruppe war dies nicht der Fall. Neurophysiologische Messungen können somit (1) den Therapieerfolg validieren, (2) Wirkmechanismen einer Therapieform berprüfen, wodurch ein Zugang zu besserer Modellierung geschaffen wird, (3) die differentialdiagnostischen Möglichkeiten erweitern und (4) uns einmal mehr lehren, dass Geist und Gehirn lediglich zwei Informationsebenen ein und desselben Phänomens darstellen. [ABSTRACT FROM AUTHOR]

Positive and negative priming (PP and NP) in schizophrenia were studied with a lexical-decision task. Probe words, presented 800 ms after the response to the prime (containing a word and a nonword), were either identical to, semantically related to, or unrelated to the prime target word (PP) or to the prime distractor word (NP). Schizophrenic patients displayed stronger semantic and repetition PP than controls after controlling for their slower responses. Significant NP was observed in both groups for word repetition only. The PP findings contrast with results from studies with similar prime-probe intervals but without prime responses. It is proposed that schizophrenic patients, because of impaired (controlled) processes of response selection, strongly benefit from (or rely on) the automatic retrieval of processing episodes containing response information. Related findings indicating automatic response facilitation in schizophrenia are discussed. [ABSTRACT FROM AUTHOR]