Safety Layers in the Railway System

Bei der Entwicklung und Änderung von Eisenbahnsystemen ist die Sicherheit ein elementarer Aspekt. Neue Systeme müssen in Deutschland den anerkannten Regeln der Technik entsprechen oder mindestens die gleiche Sicherheit aufweisen. Durch die neue europäische Gesetzgebung kann die ausreichende Sicherheit eines Systems auch durch den Vergleich mit einem Referenzsystem bestimmt werden. Die Frage nach der ausreichenden Sicherheit von neuen oder geänderten Eisenbahnsystemen wird demnach durch einen Vergleich beantwortet. Für diesen Vergleich müssen die sicherheitsrelevanten Teile des Systems identifiziert werden. Die Unterscheidung zwischen sicherheitsrelevanten und nicht-sicherheitsrelevanten Systemelementen und Regeln fällt jedoch vielen Fachleuten schwer. Ein Grund ist die in der Regel für die Sicherheitsanalyse ungeeignete Darstellung von Systemdokumentation und Regelwerken. Sie erschwert die Analyse, die Bewertung, Begutachtung und Zulassung des Systems. Ziel ist es, den an der Sicherheitsanalyse und -bewertung beteiligten Fachleuten ein Hilfsmittel zur Verfügung zu stellen, das diesen Vergleich erleichtert. Dazu wird der neue Begriff Sicherheitsschicht eingeführt und klar definiert. Die Sicherheitsschichten eines Systems bilden die Elemente für einen Vergleich der Sicherheit zweier Systeme. Um die systematische Identifikation von Sicherheitsschichten in einem Eisenbahnsystem zu ermöglichen, wird eine neue Methode entwickelt: die Methode zur Identifikation von Sicherheitsschichten in Eisenbahnsystemen (ISES-Methode). Diese Methode ist so gestaltet, dass sie sich in den bestehenden Ablauf bei der Sicherheitsanalyse und -nachweisführung einfügt. Die Anwendung der ISES-Methode und der Nutzen der Identifikation von Sicherheitsschichten werden am Beispiel eines Bahnübergangs demonstriert. Durch eine weiterführende Betrachtung der Schnittstelle zwischen den Ergebnissen der ISES-Methode und Unfallanalysen wird der Kreis der Sicherheitsbetrachtung geschlossen.When developing or changing railway systems safety is a fundamental aspect. In Germany, new systems have to be built according to codes of practice. If they are not, they must have at least the same safety. The new European legislation also allows determining the adequate level of safety of a system by performing a similarity analysis with a reference system. Thus, the question about the adequate level of safety of new or changed systems is answered by a comparison. For this comparison the safety-related parts of the system have to be identified. However, many analysts have difficulties in distinguishing safety-related from non-safety-related system elements and rules. A reason for this is the presentation of system description and rules that is generally inappropriate for safety analysis. It makes the analysis, evaluation, assessment and approval of the system difficult.The objective is to provide the professionals involved in safety analysis and evaluation with a tool that facilitates this comparison. For this purpose, the new term safety layer is introduced and clearly defined. The system’s safety layers are the elements for a comparison of the safety of two systems. A new method is developed to facilitate a systematic identification of safety layers of a railway system: the ISES method. This new method is designed in such a way that it integrates into the process of analysing and demonstrating system safety.The application of the ISES method and the advantage of identifying safety layers are demonstrated using a level crossing example. By looking at the interface between the results of the ISES method and accident analyses the circle of safety analysis is closed

Factors Affecting the Association between Ambient Concentrations and Personal Exposures to Particles and Gases

Results from air pollution exposure assessment studies suggest that ambient fine particles [particulate matter with aerodynamic diameter ≤ 2.5 μg (PM(2.5))], but not ambient gases, are strong proxies of corresponding personal exposures. For particles, the strength of the personal–ambient association can differ by particle component and level of home ventilation. For gases, however, such as ozone (O(3)), nitrogen dioxide (NO(2)), and sulfur dioxide (SO(2)), the impact of home ventilation on personal–ambient associations is untested. We measured 24-hr personal exposures and corresponding ambient concentrations to PM(2.5), sulfate (SO(4)(2−)), elemental carbon, O(3), NO(2), and SO(2) for 10 nonsmoking older adults in Steubenville, Ohio. We found strong associations between ambient particle concentrations and corresponding personal exposures. In contrast, although significant, most associations between ambient gases and their corresponding exposures had low slopes and R(2) values; the personal–ambient NO(2) association in the fall season was moderate. For both particles and gases, personal–ambient associations were highest for individuals spending most of their time in high- compared with low-ventilated environments. Cross-pollutant models indicated that ambient particle concentrations were much better surrogates for exposure to particles than to gases. With the exception of ambient NO(2) in the fall, which showed moderate associations with personal exposures, ambient gases were poor proxies for both gas and particle exposures. In combination, our results suggest that a) ventilation may be an important modifier of the magnitude of effect in time-series health studies, and b) results from time-series health studies based on 24-hr ambient concentrations are more readily interpretable for particles than for gases

Living with endometriosis: Comorbid pain disorders, characteristics of pain and relevance for daily life

BACKGROUND: Pain plays a central role in endometriosis. The complex relationship among pain characteristics, comorbid pain disorders and daily life represents a challenge for medical support. This multicentre cross‐sectional case–control study analysed the association between endometriosis‐related chronic pain and functions of daily life in 510 women with endometriosis, 265 (52%) who experienced chronic pain, either from endometriosis alone (N = 134, 26.3%) or in association with additional pain disorders (N = 131, 25.7%). METHODS: Self‐administered questionnaires from the Brief Pain Inventory and the Pain Disability Index were used to investigate associations between pain characteristics (frequency, duration, intensity) and daily life. Also, associations between different endometriosis characteristics (rASRM stage, presence of adhesions, localisation of lesions) and pain were evaluated. RESULTS: Chronic pain is negatively associated with almost all (12/14) aspects of daily life investigated, including standing, walking, sitting, defaecation, sleep, sports activities, family and domestic responsibilities, sexuality, social functioning, professional life, mood, and joy of life. Altogether, 33.7% of women with chronic pain reported moderate and 27.5% severe limitations. Comorbid pain disorders resulted in significantly more limitations. The length of pain episodes showed a particularly important influence, especially for family/domestic responsibilities (OR 22.94, p < 0.001), professional life (OR 16.56, p < 0.001) and social functioning (OR 41.03, p < 0.001). CONCLUSIONS: Our data confirm that despite treatment, about 50% of women experience pain. Pain was associated with at least moderate negative effects on almost all areas of daily life; additional pain comorbidities increased limitations. Improving pain management is essential for improving quality of life in women with endometriosis. SIGNIFICANCE: The study provides an accurate overview of the impact of endometriosis‐associated pain on daily life. This is important because pain plays a central role in women living with endometriosis, and despite modern therapies, many women continue to suffer from chronic pain. The detailed analysis of its impact with a comprehensive survey of all aspects of daily life in a very large study population is unique. We expect an improved understanding of consequences of pain to significantly advance medical support in these patients

Comparison of male and female perspective in couples involved in sexual relationships and facing endometriosis

Background While the sexuality of patients with endometriosis is an established topic in research, the possible effect of endometriosis on partnership sexuality has come to the fore only recently. To improve counseling, more information is needed on how both partners experience sexuality in the context of endometriosis. Aim Previous research regarding endometriosis and sexuality normally focused on one partner to explore couples’ intimate relations, whereas this study provides a comparison on both partners’ perspectives on their common sexuality. Methods An overall 302 couples received a questionnaire based on the Brief Index of Sexual Functioning and Sexual History Form, which was modified by endometriosis specialists to better focus on endometriosis-specific aspects. To detect different perspectives on common sexuality within the couple, the Wilcoxon test and the Pearson chi-square test were performed. Outcomes Various aspects of couple sexuality were assessed by both partners to investigate divergent perspectives between the man and the woman within a couple. Results On one hand, male and female partners seem to have divergent perspectives on sexual satisfaction in general, desired frequency of sexual contacts, and the question of the female partner engaging in sexual activity despite discomfort. On the other, they have similar perspectives on who takes initiative in sexual contacts, satisfaction with variety in the sexual relationship, and the impact of sexual limitations on their satisfaction within the partnership. Clinical implications Endometriosis research addressing issues related to sexuality should include male partners; the same applies to consulting women with endometriosis in the context of their relationships rather than as individuals. Strengths and Limitations This is the first analysis conducted on a larger scale of data from both partners in couples dealing with endometriosis. As it provides quantitative information only, some qualitative information remains unexplored. Conclusion As both partners showed tendencies to overestimate their partners’ sexual satisfaction and had different perspectives on sensitive topics in sexuality, such as the female partner engaging in sexual activity despite discomfort, addressing sexual communication could be a starting point in counseling couples dealing with endometriosis

Does the antidiabetic drug metformin affect embryo development and the health of brown trout (Salmo trutta f. fario)?

Abstract Background Due to the rising number of type 2 diabetes patients, the antidiabetic drug, metformin is currently among those pharmaceuticals with the highest consumption rates worldwide. Via sewage-treatment plants, metformin enters surface waters where it is frequently detected in low concentrations (µg/L). Since possible adverse effects of this substance in aquatic organisms have been insufficiently explored to date, the aim of this study was to investigate the impact of metformin on health and development in brown trout (Salmo trutta f. fario) and its microbiome. Results Brown trout embryos were exposed to 0, 1, 10, 100 and 1000 µg/L metformin over a period from 48 days post fertilisation (dpf) until 8 weeks post-yolk sac consumption at 7 °C (156 dpf) and 11 °C (143 dpf). Chemical analyses in tissues of exposed fish showed the concentration-dependent presence of metformin in the larvae. Mortality, embryonic development, body length, liver tissue integrity, stress protein levels and swimming behaviour were not influenced. However, compared to the controls, the amount of hepatic glycogen was higher in larvae exposed to metformin, especially in fish exposed to the lowest metformin concentration of 1 µg/L, which is environmentally relevant. At higher metformin concentrations, the glycogen content in the liver showed a high variability, especially for larvae exposed to 1000 µg/L metformin. Furthermore, the body weight of fish exposed to 10 and 100 µg/L metformin at 7 °C and to 1 µg/L metformin at 11 °C was decreased compared with the respective controls. The results of the microbiome analyses indicated a shift in the bacteria distribution in fish exposed to 1 and 10 µg/L metformin at 7 °C and to 100 µg/L metformin at 11 °C, leading to an increase of Proteobacteria and a reduction of Firmicutes and Actinobacteria. Conclusions Overall, weight reduction and the increased glycogen content belong to the described pharmaceutical effects of the drug in humans, but this study showed that they also occur in brown trout larvae. The impact of a shift in the intestinal microbiome caused by metformin on the immune system and vitality of the host organism should be the subject of further research before assessing the environmental relevance of the pharmaceutical

The Role of the Magnetic Field in the Interstellar Medium of the Post-Starburst Dwarf Irregular Galaxy NGC 1569

(abridged) NGC 1569 is a nearby dwarf irregular galaxy which underwent an intense burst of star formation 10 to 40 Myr ago. We present observations that reach surface brightnesses two to eighty times fainter than previous radio continuum observations and the first radio continuum polarization observations. These observations allow us to probe the relationship of the magnetic field of NGC 1569 to the rest of its interstellar medium. We confirm the presence of an extended radio continuum halo at 20 cm and see for the first time the radio continuum feature associated with the western Halpha arm at wavelengths shorter than 20cm. The spectral index trends in this galaxy support the theory that there is a convective wind at work in this galaxy. We derive a total magnetic field strength of 38 microG in the central regions and 10-15 microG in the halo. The magnetic field is largely random in the center of the galaxy; the uniform field is ~3-9 microG and is strongest in the halo. We find that the magnetic pressure is the same order of magnitude but, in general, a factor of a few less than the other components of the interstellar medium in this galaxy. The uniform magnetic field in NGC 1569 is closely associated with the Halpha bubbles and filaments. We suggest that a supernova-driven dynamo may be operating in this galaxy. The outflow of hot gas from NGC 1569 is clearly shaping the magnetic field, but the magnetic field in turn may be aiding the outflow by channeling gas out of the disk of the galaxy. Dwarf galaxies with extended radio continuum halos like that of NGC 1569 may play an important role in magnetizing the intergalactic medium.Comment: ApJ accepted. 56 pages, 14 figures (low resolution), 8 tables. Version with high resolution figures at http://www.astro.virginia.edu/~aak8t/data/n1569/ms.pd

Outcomes of renal replacement therapy in boys with prune belly syndrome : findings from the ESPN/ERA-EDTA Registry

As outcome data for prune belly syndrome (PBS) complicated by end-stage renal disease are scarce, we analyzed characteristics and outcomes of children with PBS using the European Society for Pediatric Nephrology/European Renal Association-European Dialysis and Transplant Association (ESPN/ERA-EDTA) Registry data. Data were available for 88 male PBS patients aged <20 years who started renal replacement therapy (RRT) between 1990 and 2013 in 35 European countries. Patient characteristics, survival, and transplantation outcomes were compared with those of male patients requiring RRT due to congenital obstructive uropathy (COU) and renal hypoplasia or dysplasia (RHD). Median age at onset of RRT in PBS was lower [7.0; interquartile range (IQR) 0.9-12.2 years] than in COU (9.6; IQR: 3.0-14.1 years) and RHD (9.4; IQR: 2.7-14.2 years). Unadjusted 10-year patient survival was 85% for PBS, 94% for COU, and 91% for RHD. After adjustment for country, period, and age, PBS mortality was similar to that of RHD but higher compared with COU [hazard ratio (HR) 1.96, 95% confidence interval (CI) 1.03-3.74]. Seventy-four PBS patients (84%) received a first kidney transplant after a median time on dialysis of 8.4 (IQR 0.0-21.1) months. Outcomes with respect to time on dialysis before transplantation, chance of receiving a first transplant within 2 years after commencing RRT, and death-censored, adjusted risk of graft loss were similar for all groups. This study in the largest cohort of male patients with PBS receiving RRT to date demonstrates that outcomes are comparable with other congenital anomalies of the kidney and urinary tract, except for a slightly higher mortality risk compared with patients with COU.Peer reviewe

Quantification of the response of circulating epithelial cells to neodadjuvant treatment for breast cancer: a new tool for therapy monitoring

INTRODUCTION: In adjuvant treatment for breast cancer there is no tool available with which to measure the efficacy of the therapy. In contrast, in neoadjuvant therapy reduction in tumour size is used as an indicator of the sensitivity of tumour cells to the agents applied. If circulating epithelial (tumour) cells can be shown to react to therapy in the same way as the primary tumour, then this response may be exploited to monitor the effect of therapy in the adjuvant setting. METHOD: We used MAINTRAC(® )analysis to monitor the reduction in circulating epithelial cells during the first three to four cycles of neoadjuvant therapy in 30 breast cancer patients. RESULTS: MAINTRAC(® )analysis revealed a patient-specific response. Comparison of this response with the decline in size of the primary tumour showed that the reduction in number of circulating epithelial cells accurately predicted final tumour reduction at surgery if the entire neoadjuvant regimen consisted of chemotherapy. However, the response of the circulating tumour cells was unable to predict the response to additional antibody therapy. CONCLUSION: The response of circulating epithelial cells faithfully reflects the response of the whole tumour to adjuvant therapy, indicating that these cells may be considered part of the tumour and can be used for therapy monitoring

Coronary optical frequency domain imaging (OFDI) for in vivo evaluation of stent healing: comparison with light and electron microscopy

The present study demonstrates that OFDI is a highly promising tool for accurate evaluation of coronary stent strut coverage, as supported by a high agreement between OFDI and light and electron microscopic analysis. Furthermore, our data indicate that optical density measurements can provide additional information with respect to the type of stent strut coverage, i.e. fibrin vs. neointimal coverage. Therefore, coronary OFDI analysis will provide important information on the biocompatibility of coronary stents