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For model validation, quantitative measurements of the evolution of moisture, temperature, and pressure distributions in time are needed. For this purpose, we have developed an NMR setup to measure the moisture transport in heated building materials. The measured combined moisture content and temperature profiles give a unique insight in the moisture transport and dehydration kinetics inside concrete during fire. These measurements give the first quantitative proof for the build-up of a moisture peak due to the vapor pressure build-up. In this study we have also combined for the first time the measurement of the moisture and temperature profiles with the measurement of the pressure at one position, which show that the pressure build up is directly related to the moisture profiles.

Mechanical loading is an important parameter of spalling phenomenon likely to occur in concrete during heating. Several tests in laboratory have shown an increase of the risk of spalling in the compressed areas. In this study, a specific metallic frame has been developed to apply uniaxial and biaxial stresses on slabs during fire tests. Tests carried out on an ordinary concrete (fc28 = 37 MPa) exposed to ISO 834-1 temperature curve with several levels of uniaxial loading are presented. No spalling was observed when samples were loaded at 0, 5 and 10 MPa. In the opposite, spalling was observed when the compressive stress was increased to 15 MPa.

Results are presented from experimental work on the high-temperature behavior of conventional vibrated high-strength concrete and self-compacting high-strength concrete. Concrete cylindrical specimens and prismatic specimens were subjected to a low heating rate of 0.5°C/min (up to 400°C) and a high heating rate according to International Standard Organization 834 fire curve (up to 600°C). The experimental results show that the residual mechanical properties in reference to initial mechanical properties of self-compacting high-strength concretes were similar to that of conventional high-strength concrete. The risk of spalling for self-compacting high-strength concrete was greater than that of conventional high-strength concrete. As for the conventional vibrated high-strength concrete, the use of polypropylene fiber improved the thermal stability of self-compacting high-strength concrete. Adding polypropylene fiber modified thermal gradient (in consequence thermal stresses) in the tested concrete specimens during the heating–cooling cycles. This may contribute to explaining the difference in thermal stability. [ABSTRACT FROM AUTHOR]

Background: Prospective birth cohorts are essential for identifying associations between exposures and outcomes. However, voluntary participation introduces a potential bias due to self selection since the persons that chose to participate may differ in background characteristics and behaviors., Objectives: To investigate potential bias due to self-selection in the N utritional impact on I mmunological maturation during C hildhood in relation to the E nvironment (NICE) birth cohort in northern Sweden., Methods: Women in the NICE birth cohort ( N  = 621) were compared to nonparticipating pregnant women in Norrbotten County in northern Sweden who were eligible for participation ( N  = 4976) regarding maternal characteristics and lifestyle. Maternal characteristics and pregnancy outcomes were compared between the groups and associations between exposures (smoking, folic acid, BMI, parity, education) and pregnancy outcomes (birth weight and gestational age) were analyzed by linear regression analyses, examining any interaction with the group., Results: NICE participants were more highly educated, older and more likely to cohabit than the non-participants. They more often took folic acid and multivitamin supplements and less often smoked during early pregnancy. Pregnancy outcomes (mode of delivery, gestational age at delivery, birth weight and APGAR score) did, however, not differ significantly between participants and non-participants. Smoking, BMI, education and parity affected gestational age and birth weight, but the associations were of similar magnitude in participants and non-participants, with no significant effect on the group., Conclusion: Self-selection to the NICE study was evident in some factors related to lifestyle and socioeconomic characteristics but did not appear to skew pregnancy outcomes or alter well-known effects of certain lifestyle parameters on pregnancy outcomes.

Background: Long-term research is crucial for the conservation and development of knowledge in ecology; however, it is essential to quantify and minimize any negative effects associated with research to gather reliable and representative long-term monitoring data. In colonial bird species, chicks are often marked with coded bands in order to assess demographic parameters of the population. Banding chicks in multi-species colonies is challenging because it involves disturbances to species that are at different stages of progress in their reproduction., Methods: We took advantage of a long term banding program launched on Glossy Ibis ( Plegadis falcinellus ) breeding in a major mixed colony of herons in Camargue, southern France, to assess the effect of banding operation disturbance on the reproductive success of the three most numerous waterbirds species in the colony. Over two breeding seasons (2015 and 2016), 336 nests of Glossy Ibis, Little Egrets ( Egretta garzetta ) and Cattle Egrets ( Bubulcus ibis ) were monitored from a floating blind in two zones of the colony: one zone disturbed twice a year by the banding activities and another not disturbed (control zone). We applied a logistic-exposure analysis method to estimate the daily survival rate (DSR) of nests and chicks aged up to three weeks., Results: Daily survival rate of Glossy Ibis was reduced in the disturbed zone while DSR increased for Little and Cattle Egrets in the disturbed zone. Nevertheless, DSR was not reduced on the week following the banding, thus discarding a direct effect of handling on breeding success of Glossy Ibis. The protocol and statistical analysis presented here are robust and can be applied to any bird species to test for the effect of a research disturbance or other short and repeated temporal events that may affect reproductive success over one or more breeding seasons., Competing Interests: The authors declare there are no competing interests., (©2019 Champagnon et al.)

Objectives: We aimed to investigate how an infection with Chlamydia trachomatis (CT) influenced patients' well-being and whether there were differences due to gender, age or relationship status, in an effort to strengthen preventive measures and provide better healthcare for patients with CT., Methods: Patients diagnosed with CT in the county of Västerbotten, Sweden, were asked to fill out a questionnaire about their feelings, thoughts and actions after CT diagnosis. The patients were also asked to fill in the validated questionnaires Hospital Anxiety and Depression Scale and Alcohol Use Disorder Identification Test. Between February 2015 and January 2017, 128 patients (74 women and 54 men) were included in the study., Results: After being diagnosed with CT, men were generally less worried than women (P<0.001). Women worried more about not being able to have children (P<0.001) and about having other STIs (P=0.001) than men did. Men felt less angry (P=0.001), less bad (P<0.001), less dirty (P<0.001) and less embarrassed (P=0.011) than women did. Nineteen per cent of men and 48% of women reported symptoms of anxiety. The majority of both men (60%) and women (72%) had a risk consumption of alcohol., Conclusion: Women and men reacted differently when diagnosed with CT. Women worried more about complications and more often blamed themselves for being infected. Being aware of these gender differences may be important when planning preventive measures and during counselling of CT-infected patients. Persons working with patients with CT must also be aware of the high frequency of harmful alcohol consumption among their patients., Competing Interests: Competing interests: None declared., (© Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.)

Unlabelled: Contact tracing is proved to be a good way to prevent asymptomatic sexually transmitted infections, such as Chlamydia trachomatis, from spreading. According to the Swedish law a physician has to report all cases of genital C. trachomatis to the County Medical Officer of Health and to the National institute for Infectious Disease Control and perform contact tracing. An evaluation of the sexual history 6 months back in time is recommended and standard in most of the country. The county of Västerbotten has one of the lowest incidenses of C. trachomatis in Sweden though the population is younger than the Swedish average. During year 2002 the contact tracing in Västerbotten was evaluated by sending a questionnaire to everyone who reported a case of genital C. trachomatis. We recived 534 (98%) out of 544 questionnaires. The patients reported 1360 partners, 2.5 on average, 1129 were identified. 761 had a known test result and 497 of them were positive, 0.9 on average. 72% of the contact tracers evaluated the sexual history > or = 12 months back in time. 78% of the contact tracings were performed by four social workers. Their patients reported 2.5 partners on average and 80% evaluated > or = 12 months back in time. 14 persons did only one contact tracing, 1.3 partners/index on average, 40% evaluated > or = 12 months back in time. 82% of the partners had sex with the infected patient 0-6 months before the patients was diagnosed with C. trachomatis, 75% out of those with a known test result were infected, 16% had sex 7-12 months before diagnosis, 30% infected. (The C. trachomatis prevalence in Sweden is estimated to be 2.7-4.9% among young women.), Conclusion: A few experienced persons tracing for at least 12 month back in time is probably two important reasons why Västerbotten has such a small C. trachomatis incidence.