Measured Time Periods Research Articles

Mitochondrial DNA copy number variation, leukocyte telomere length, and breast cancer risk in the European Prospective Investigation into Cancer and Nutrition (EPIC) study

BackgroundLeukocyte telomere length (LTL) and mitochondrial genome (mtDNA) copy number and deletions have been proposed as risk markers for various cancer types, including breast cancer (BC).MethodsTo gain a more comprehensive picture on how these markers can modulate BC risk, alone or in conjunction, we performed simultaneous measurements of LTL and mtDNA copy number in up to 570 BC cases and 538 controls from the European Prospective Investigation into Cancer and Nutrition (EPIC) cohort. As a first step, we measured LTL and mtDNA copy number in 96 individuals for which a blood sample had been collected twice with an interval of 15 years.ResultsAccording to the intraclass correlation (ICC), we found very good stability over the time period for both measurements, with ICCs of 0.63 for LTL and 0.60 for mtDNA copy number. In the analysis of the entire study sample, we observed that longer LTL was strongly associated with increased risk of BC (OR 2.71, 95% CI 1.58–4.65, p = 3.07 × 10− 4 for highest vs. lowest quartile; OR 3.20, 95% CI 1.57–6.55, p = 1.41 × 10− 3 as a continuous variable). We did not find any association between mtDNA copy number and BC risk; however, when considering only the functional copies, we observed an increased risk of developing estrogen receptor-positive BC (OR 2.47, 95% CI 1.05–5.80, p = 0.04 for highest vs. lowest quartile).ConclusionsWe observed a very good correlation between the markers over a period of 15 years. We confirm a role of LTL in BC carcinogenesis and suggest an effect of mtDNA copy number on BC risk.

Effects of local anesthetic or systemic analgesia on pain associated with cautery disbudding in calves: A systematic review and meta-analysis

Disbudding is a common management procedure performed on dairy farms and, when done without pain mitigation, is viewed as a key welfare issue. Use of pain control has increased in recent years, but full adoption of anesthesia and analgesia by veterinarians or dairy producers has not been achieved. This may in part be due to the lack of a consistent recommendations of treatment protocols between studies examining pain control methods for disbudding. The objective of this systematic review was to examine the effects of these pain control practices for the most common method of disbudding, cautery, on outcomes associated with disbudding pain in calves. The outcomes were plasma cortisol concentrations, pressure sensitivity of the horn bud area, and validated pain behaviors (ear flick, head shake, head rub, foot stamp, and vocalization). Intervention studies describing cautery disbudding in calves 12 wk of age or younger were eligible, provided they compared local anesthesia, nonsteroidal anti-inflammatory drug (NSAID), or local anesthesia and NSAID to 1 or more of local anesthesia, NSAID, or no pain control. The search strategy used the Agricola, Medline (via OvidSP), and Web of Science databases, as well as the Searchable Proceedings of Animal Conferences (S-PAC), ProQuest Dissertations and Theses Database, and Open Access Theses and Dissertations. Meta-analysis was performed for all outcomes measured at similar time points with more than 2 studies. Local anesthetic was associated with reduced plasma cortisol until 2 h postdisbudding; however, a rise in cortisol was observed in the meta-analysis of studies reporting at 4 h postdisbudding. Heterogeneity was present in several of the analyses for this comparison. The addition of NSAID to local anesthetic showed reduction in plasma cortisol at 4 h, and a reduction in pressure sensitivity and pain behaviors in some analyses between 3 and 6 h postdisbudding. Heterogeneity was present in some meta-analyses, including several using pain behavior outcomes. This may reflect the variation in measurement time periods for behavioral measures between studies, as well as differences among NSAID treatments. Overall, a protective effect of local anesthetic was seen for the acute pain of cautery disbudding, and the delayed rise in cortisol was mitigated by the addition of an NSAID, which also reduced other signs of pain, including pressure sensitivity and pain behaviors. Based on these findings, we recommend use of local anesthetic and an NSAID as best practices for pain mitigation for cautery disbudding of calves 12 wk of age or less. The magnitude and duration of the effect of NSAID treatment was not possible to deduce from the literature because wide variation existed between studies. We recommend consideration of more standardized outcome measurements, especially for pain behaviors. Adherence to reporting guidelines by authors would help ensure more transparent and complete information is available to end users.

Numerical modeling of energy transfer in underground borehole heat exchanger within unsaturated soil

In the current study, the heat emission and heat extraction process is numerically studied for six u-shaped upright underground pipes during a 10 day period. The soil medium is considered to be unsaturated, which is the common case in most of the practical scenarios. For this purpose, the convective flows of dry air, water vapour, and surface water are simultaneously accounted for and the energy transfer amounts are estimated. Also, the radial distributions of temperature and moisture content are acquired for the 2nd, 4th, and 10th days by minimizing the residual norm's value. The study mostly aims to obtain the results which yield a good insight into the efficiency of the system, which in case of further analysis could be used for the design purposes of heat pipe arrangement. It is shown that, for a constant 70 W/m2 of heat emission and for the distances more than 1.5 m from the heat source, the amount of wasted energy remains approximately the same, independent of the measurement time period. Also, it is calculated that about 83.3% of the storable energy is stored in the medium by the end of the 6th day; and 10% of the aggregated stored energy is wasted through convective heat flows, by the end of the 10th day.

Vibration‐Based Damage Identification and Condition Monitoring of Metro Trains: Warsaw Metro Case Study

The work concerns the monitoring of the technical condition of metro trains. For this purpose, a vibration monitoring system installed in buildings in the vicinity of the underground is used. Based on measured vibrations buildings, the identification of technical condition in metro trains is conducted. The results of measurements from the system are also used to assess the impact of vibrations on people staying in buildings through the WODL ratio. Exceeding the assumed levels of the WODL ratio is the basis for repairing trains by turning wheels. Statistical analysis of the data was implemented and trends for particular time periods of measurements were shown. With the entered monitoring system and the introduced WODL index thresholds, it is possible to better plan the costs associated with the repair and replacement of wheels of rolling stock, where there are large values of radial runout. According to the introduced monitoring procedure, the number of complaints from residents decreased and the comfort of their lives improved.

Investigation of Power Quality in a Hybrid Power System- The case of Paros island complex

This paper examines the power quality of the nine islands complex in Aegean Sea (Paros island complex), which are connected to each other by submarine cables. The power supply of this island complex is provided by a power station (DIESEL) of nominal power 79.43 MW and by renewable energy plants (6 wind farms totaling 13.960 kW) and 34 photovoltaic stations totaling 2982.745 kW, which are located in the islands of the complex. Due to the structure power generation and distribution system in this island complex, it has been considered necessary to study the power quality, which is affected mainly by the connection and disconnection of renewable energy sources as well as the physical characteristics of these sources. The influence of variations in the power parameters of the renewable sources and the harmonic content of electrical quantities were critical issues to be investigated at two selected locations for reasonable time intervals. The assessment of the power quality was done in accordance with the international standards and mainly according to the standard EN 50160. The DRANETZ measurement system recorded the attributable power / energy of the renewable sources and corresponding time plots were formed for the time periods of measurements. Also have been recorded interruptions and reconnections of renewable sources with the grid. It was found that all the standard claims were met and taken in account the experience of the system operator we had concluded that in the island complex the quality was satisfactory. The aim of this investigation was to extract useful information about the power quality and to show how have to work in practice to evaluate the power quality .

Pregnancy-induced Changes in Corneal Biomechanics and Topography Are Thyroid Hormone Related

To identify biomechanical and topographic changes of the cornea during pregnancy and the postpartum period and its association to hormonal changes. Prospective single-center observational cohort study. Participants were 24 pregnant women (48eyes), monitored throughout pregnancy and after delivery. Biomechanical and topographic corneal properties were measured using the Ocular Response Analyzer (ORA) and a Scheimpflug imaging system (Pentacam HR) each trimester and 1month after delivery. At the same consultations blood plasma levels of estradiol (E2) and thyroid hormones (TSH, T3t, T4t) were also determined. A factorial MANCOVA was used to detect interactions between hormonal plasma levels and ocular parameters. Significant differences in corneal biomechanical and topographic parameters were found during pregnancy in relation to T3t (p= .01), T4t (p<.001), T3t/T4t (P= .001), and TSH (p=.001) plasma levels. E2 plasma levels (p= .092) and time period of measurement (p= .975) did not significantly affect corneal parameters. TSH levels significantly affected the maximal keratometry reading (p=.036), the vertical keratometry reading (p=.04), and the index of height asymmetry (p=.014). Those results persist after excluding hypothyroidism patients from the statistical analysis. Hormonal changes affecting corneal biomechanics and topography during pregnancy could be thyroid related. Dysthyroidism may directly influence corneal biomechanics and represents a clinically relevant factor that needs further investigation.

Quantitative characterization of cuticular barrier properties: methods, requirements, and problems.

The interface between the atmosphere and leaves and fruits is formed by the lipophilic plant cuticle, which seals the outer epidermal cell walls, thus significantly reducing water loss and uptake of dissolved solutes deposited on the cuticle surface. Different experimental and theoretical approaches for quantifying barrier properties of cutinized leaf and fruit surfaces are presented and discussed in this review. Quantitative characterization of cuticle barrier properties requires (i) the measurement of diffusion kinetics, namely the amount diffusing versus time, (ii) accurate knowledge of driving forces, namely concentration gradients, acting across the barrier, and (iii) the calculation of permeances, namely diffusion velocity. We suggest that on the basis of permeances, which are independent from experimental boundary conditions such as driving forces, the time period of measurement, and area, cuticle barrier properties of different plant organs, different plant species, and different lines, as well as barrier properties of suberized root tissue or synthetic membranes, can be directly compared. This review provides a short and easy to understand manual on what should be kept in mind when quantifying barrier properties of cutinized and suberized transport barriers. This could be helpful for scientists working on cuticle biosynthesis and its regulation.

Uncertainty based model averaging for prediction of long-time prestress losses in concrete structures

Prestressed concrete structures are widely used in long span bridge girders and nuclear power plants. Long-time creep and shrinkage in concrete cause loss of prestress forces in the concrete structures. The creep and shrinkage models existing in the literature are empirical in nature. Each model has been developed on the basis of an arbitrary selection of data sets among all the data sets available. In this study it is claimed that each model contains some information about the creep and shrinkage patterns in the concrete structures. A single best model is developed in this study using all existing models, based on the concept of model averaging. In model averaging all the models are updated independently based on the short-time measurements. Weights are assigned to each model based on the likeliness of predictions from that model to the actual measurements. The time period for short-time measurements is evaluated using stochastic simulations. The proposed single best model for creep and shrinkage, and the time period for short-time measurements are (i) first validated against experiments reported in the Northwestern University (NU) database, and (ii) then used to predict the long-time losses of prestress forces in the concrete beams and slabs cast in the laboratory.

Characterization of interfacial reactions and oxide films on 316L stainless steel in various simulated PWR primary water environments

The effect of water chemistry on the electrochemical and oxidizing behaviors of 316L SS was investigated in hydrogenated, deaerated and oxygenated PWR primary water at 310 °C. Water chemistry significantly influenced the electrochemical impedance spectroscopy parameters. The highest charge-transfer resistance and oxide-film resistance occurred in oxygenated water. The highest electric double-layer capacitance and constant phase element of the oxide film were in hydrogenated water. The oxide films formed in deaerated and hydrogenated environments were similar in composition but different in morphology. An oxide film with spinel outer particles and a compact and Cr-rich inner layer was formed in both hydrogenated and deaerated water. Larger and more loosely distributed outer oxide particles were formed in deaerated water. In oxygenated water, an oxide film with hematite outer particles and a porous and Ni-rich inner layer was formed. The reaction kinetics parameters obtained by electrochemical impedance spectroscopy measurements and oxidation film properties relating to the steady or quasi-steady state conditions in the time-period of measurements could provide fundamental information for understanding stress corrosion cracking processes and controlling parameters.

Statistical analysis of the electric energy production from photovoltaic conversion using mobile and fixed constructions

The paper presents the most representative – from the three-year measurement time period – characteristics of daily and monthly electricity production from a photovoltaic conversion using modules installed in a fixed and 2-axis tracking construction. Results are presented for selected summer, autumn, spring and winter days. Analyzed measuring stand is located on the roof of the Faculty of Electrical Engineering Poznan University of Technology building. The basic parameters of the statistical analysis like mean value, standard deviation, skewness, kurtosis, median, range, or coefficient of variation were used. It was found that the asymmetry factor can be useful in the analysis of the daily electricity production from a photovoltaic conversion. In order to determine the repeatability of monthly electricity production, occurring between the summer, and summer and winter months, a non-parametric Mann-Whitney U test was used as a statistical solution. In order to analyze the repeatability of daily peak hours, describing the largest value of the hourly electricity production, a non-parametric Kruskal-Wallis test was applied as an extension of the Mann-Whitney U test. Based on the analysis of the electric energy distribution from a prepared monitoring system it was found that traditional forecasting methods of the electricity production from a photovoltaic conversion, like multiple regression models, should not be the preferred methods of the analysis.

The Effects of Some Drinks on Saliva pH

Objectives: The purpose of this study is to evaluate the effects of some drinks on saliva pH. Methods: Systemic and periodontally healthy individuals aged 18-23 years were included in the study. Individuals saliva pHs were measured three hours after breakfast. Three groups were set up to measure after 1 minute, 10 minutes and 30 minutes after drinks were drunk and the effects of Turkish coffee, cola, ayran and green tea on saliva pH were investigated. Results: The most pronounced pH changes occurred in the first group. The lowest pH values were reached when cola was consumed while the highest pH values were reached when green tea was consumed. Within the pH measurement time period, the drink group with the least tendency of pH value change was green tea. Conclusion: In order to prevent tooth decay, there is a need to raise awareness about conscious and controlled consumption of beverages that may lead to significant reductions in salivary pH.

Intellectual Capital: A Review from the Literature

Purpose - The purpose of this paper is to get a clear concept about intellectual capital and reports on intellectual capital in different entities based on the literature review. Research design, data, and methodology - This study was mainly written in a way of descriptive research. The current studies deal with the theoretical and reporting aspects on intellectual capital. Thus, this research is developed on the basis of previous descriptive and empirical research papers. Results - This study finds that intellectual capital is the combination of human capital, structural capital and relational capital but there is no unique measurement system or process to define intellectual capital. The findings also indicates that the measurement for intellectual capital varies based on the measurement process, time period, firms, industries and country to country perspectives. It can be also observed that firms have the tendency not to disclose the intellectual capital information. Conclusions - This study recommends that intellectual capital should be presented in a fixed format and human, relational and structural capital should be included as intellectual capital. Additionally, it suggests that mandatory requirement of legislation, effective corporate governance mechanism and stock exchange listing requirement might increase the quality of intellectual reporting.

The response of tree ring δ15N to whole-watershed urea fertilization at the Fernow Experimental Forest, WV

Plant tissue δ15N is frequently used as a proxy for N availability and N cycle dynamics, and the δ15N signature of tree rings could potentially be used to reconstruct past changes in the N cycle due to forest disturbance or anthropogenic N deposition. However, there are substantial uncertainties regarding how effectively tree ring δ15N records N cycle dynamics. We used increment tree cores from a forested watershed that received a one-time application of urea, along with the long-term stream water chemistry record from that watershed and a nearby reference watershed, to determine the effectiveness of tree ring δ15N in recording a change in N availability, and whether its effectiveness differed by species or mycorrhizal type. Tree ring δ15N of three species increased rapidly (within ~1 to 3 years) following fertilization (Quercus rubra, Fagus grandifolia, and Prunus serotina), while that of Liriodendron tulipifera did not respond to fertilization but increased ~10 years later. Tree ring δ15N tended to remain elevated throughout the measured time period (1967–2000), well past the pulsed fertilization response in stream water. This extended δ15N response may be partially caused by chronic atmospheric N deposition in the region, which also contributed to greater losses of nitrate in stream water by ~1980. Additionally, local recycling of N compounds, and retranslocation of N within the trees, may account for the persistence of elevated tree ring δ15N levels beyond the direct fertilization effects. Collectively, these results confirm that tree ring δ15N from some species can document the onset of historical changes in the N cycle. We suggest that studies utilizing tree ring δ15N as a proxy for long-term N cycle dynamics should look for a consistent pattern of change among several species rather than relying on the record from a single species.

Frequency and clinical relevance of potential cytochrome P450 drug interactions in a psychiatric patient population - an analysis based on German insurance claims data.

BackgroundNumerous drugs used in the treatment of psychiatric disorders are substrates of cytochrome P450 enzymes and are potential candidates for drug-drug interactions (DDIs).MethodsClaims data of a German statutory health insurance company from severely mentally ill patients who registered in an integrated care contract from August 2004 to December 2009 were analysed. We measured time periods of concomitant prescription of drugs that have been reported to interact via cytochrome P450, with a focus on drugs acting as strong inhibitors. Such drug-drug exposure (DDE) is an incontrovertible precursor of DDIs. We assessed whether potential DDIs were considered clinically relevant based on the prescribing information of the respective drugs.ResultsAmong all 1221 patients, 186 patients (15.2 %; Clopper-Pearson 95 % confidence interval (CI): 13.3–17.4 %) had at least one DDE prescription, and 58 patients (4.8 %; 95 % CI 3.6–6.1) had at least one DDE prescription involving a strong cytochrome P450 inhibitor. In 59 patients, (4.8 %; 95 % CI: 3.7–6.2 %) five or more DDEs were identified, and five or more DDEs with a strong inhibitor were identified in 18 patients (1.5 %; 95 % CI: 0.9–2.3). The rates of DDEs were 0.27 (Garwood 95%CI: 0.25–0.28) per person-year and 0.07 (95 % CI: 0.07–0.08) for strong-inhibitor DDEs. Four of the ten most frequent DDEs were identified as clinically relevant, and seven of the eight most frequent DDEs involving a strong inhibitor were clinically relevant.ConclusionsThe number of patients with DDEs was not alarmingly high in our sample. Nevertheless, prescription information showed that some prescribed drug combinations could result in serious adverse consequences that are known to weaken or strengthen the effect of the drugs and should therefore be avoided.

The uncertainty in the radon hazard classification of areas as a function of the number of measurements

The administration in many countries demands a classification of areas concerning their radon risk taking into account the requirements of the EU Basic Safety Standards. The wide variation of indoor radon concentrations in an area which is caused by different house construction, different living style and different geological situations introduces large uncertainties for any classification scheme. Therefore, it is of importance to estimate the size of the experimental coefficient of variation (relative standard deviation) of the parameter which is used to classify an area. Besides the time period of measurement it is the number of measurements which strongly influences this uncertainty and it is important to find a compromise between the economic possibilities and the needed confidence level. Some countries do not use pure measurement results for the classification of areas but use derived quantities, usually called radon potential, which should reduce the influence of house construction, living style etc. and should rather represent the geological situation of an area. Here, radon indoor measurements in nearly all homes in three municipalities and its conversion into a radon potential were used to determine the uncertainty of the mean radon potential of an area as a function of the number of investigated homes. It could be shown that the coefficient of variation scales like 1/√n with n the number of measured dwellings. The question how to deal with uncertainties when using a classification scheme for the radon risk is discussed and a general procedure is proposed.

THE EFFECTS OF APPLYING COMMUNICATION TOOLS BASED ON CONNECTIVISM THEORY ON STUDENTS’ ACADEMIC ACHIEVEMENT AND THE VALUE OF THEIR ENGAGEMENT

Today, with the increase in communication means and their impact on learning, educational environment is changing. The aim of the present study was to investigate the use of communication tools based on connectivism theory on students’ academic achievement and the value of their engagement. The statistical population of the study consisted of the students studying as sophomore in high school, district 3, Tehran City. In this study, sampling method was “available sampling” and two 15-students classes formed the experimental and control group. This research was based on a quasiexperimental design, pretest, posttest, and follow-up with the control group. The experimental group was treated by teaching chemistry through a website while the control group was treated by teaching chemistry traditionally. The treatment continuously lasted for three days a week for a semester. The tools to gather the required data include survey test of students’ engagement in high school and the questionnaire prepared by the researcher for chemistry lesson. ANOVA test with repeated measures was used to analyze data. The results obtained indicated learning stability and confirmed there was a significant difference between students’ scores in different time periods of measurement in experimental group and. According to the results, teaching by the use of communication means in addition to showing a significant difference with the traditional method of teaching has a positive and significant effect on chemistry lesson; however, no significant differences were seen in students’ engagement in the two groups.

Randomised Controlled Trial of Ankle Block Versus Metatarsal Block for First Ray Surgery

Category: Bunion Introduction/Purpose: First ray arthrodesis or osteotomy is a day surgery procedure performed commonly under general anaesthetic. One of the aims with such procedures is to ensure our patients are discharged on the day of surgery and are relatively pain free on discharge. This is often achieved by the use of local anaesthetic blockades, either as an ankle block or as a metatarsal block. There are studies published on the effectiveness of ankle block for first ray surgery but there is a dearth of studies on metatarsal block. Therefore the aim of this study is to compare the effectiveness of ankle block versus metatarsal block in conjunction to general anaesthetic for first ray surgery. Methods: Both local trust board approval and National Research Ethics Committee approval were granted for the study. Statistical analysis to ensure an adequately powered study was performed. Fifty patients undergoing arthrodesis or osteotomy of the first ray were recruited into this study and randomly allocated to the cohort to receive either a metatarsal block or an ankle block. All patients had general anaesthesia. Those patients randomized to ankle block had this performed after induction of general anaesthesia using ultrasonography. Those patients randomized to metatarsal block had this performed at the end of the operative procedure. Patients scored their pain level using a visual analogue scale (0-10) at 2, 6 and 24 hours. A physiotherapist, who was blinded to their treatment arm, assessed patients at hourly intervals from two hours. Patients were contacted by telephone by a research nurse, who was also blinded to their treatment arm, over 24 hours from discharge. Results: Forty-eight patients completed the study: 25 in the ankle block treatment arm and 23 in the metatarsal block arm. The majority of the patients were female (44 patients) with an average age of 53 years (range 31-76 years). Analysis of pain scores showed that there was no statistically significant difference between the two groups at any of the measured time periods. Analysis of their analgesic requirement in the first 24 hours after surgery again revealed no striking difference between the two cohorts. Similarly analysis of the time taken to safely mobilise revealed that there was no difference between the two groups. However analysis of the time taken to perform the anaesthesia highlighted a mean addition of eleven minutes when an ultrasound guided ankle block was performed. Conclusion: This prospective randomised blinded study demonstrates that metatarsal blocks are just as effective in giving post- operative analgesia as ultrasound guided ankle blocks in patients undergoing first ray surgery under general anaesthetic.

Fourier transform spectrometer measurements of column CO&amp;lt;sub&amp;gt;2&amp;lt;/sub&amp;gt; at Sodankylä, Finland

Abstract. Fourier transform spectrometer (FTS) observations at Sodankylä, Finland (67.4° N, 26.6° E) have been performed since early 2009. The FTS instrument is participating in the Total Carbon Column Observing Network (TCCON) and has been optimized to measure abundances of the key greenhouse gases in the atmosphere. Sodankylä is the only TCCON station in the Fennoscandia region. Here we report the measured CO2 time series over a 7-year period (2009–2015) and provide a description of the FTS system and data processing at Sodankylä. We find the lowest monthly column CO2 values in August and the highest monthly values during the February–May season. Inter-annual variability is the highest in the June–September period, which correlates with the growing season. During the time period of FTS measurements from 2009 to 2015, we have observed a 2.2 ± 0.2 ppm increase per year in column CO2. The monthly mean column CO2 values have exceeded 400 ppm level for the first time in February 2014.

Swedish translation and linguistic validation of the multidimensional dyspnoea profile

BackgroundDyspnoea, the feeling of breathing discomfort, consists of multiple dimensions that can vary in intensity, including the level of unpleasantness, qualities or descriptors of the sensation, emotional responses, and impact on function. No validated instrument for multidimensional measurement of dyspnoea is available in Swedish. The Multidimensional Dyspnea Profile (MDP) was recently developed to measure the unpleasantness, sensory qualities, and emotional responses of dyspnoea across diseases and settings. We aimed to take forward a Swedish version of the MDP.MethodsTranslation and linguistic validation of the MDP was conducted in collaboration with a specialised company in the field (Mapi, Lyon, France). The structured process involved forward and backward translations by two independent certified translators, input from an in-country linguistic consultant, the developers, and three respiratory physicians. Understandability and acceptability were evaluated through in-depth interviews with five patients with dyspnoea in accordance with international guidelines.Results and ConclusionA Swedish version of the MDP was obtained and linguistically validated. The MDP includes 11 rated items: the immediate unpleasantness of the sensation, the presence and intensity of five sensory qualities, and the intensity of five emotional responses to dyspnoea. The time period of measurement is specified by the user. The MDP is copyrighted by the developers but can be used free of charge in the context of non-funded academic research.ConclusionThe MDP is the first instrument for measuring multiple dimensions of dyspnoea available in Swedish and should be validated across diseases and settings. Multidimensional measurement is essential for improved assessment and management of dyspnoea in research and clinical care.

Influence of the Straining Level on the Long-Lasting Relaxation Behaviour of Polyester Yarns

The main problem in the investigation and prediction of stress relaxation is the long time periods (not in seconds or minutes but in days or even months) of measurements for each kind of textile, especially in cases where users need to know the behaviour of the textile in prolonged time usage. Previously it was found that the rate of relaxation on the log scale can be described by two straight lines and the values of relaxation can be predicted over a long time by the rate of relaxation of the second linear dependency. The present paper shows investigations of 29.4 tex polyester yarn’s relaxation behaviour at different levels of elongation, i.e. at 3, 5, 7 and 10%. Investigations show that the place of the break-point of relaxation depends on the level of elongation – by increasing the level of elongation the time decreases till the break-point. This phenomenon is clearly visible at higher levels of elongation, while at low levels (3 and 5%) the difference is quite small. Using the data presented, it is possible to predict long-lasting relaxation without long-lasting experiments; only shorter than 1000 second tests are needed.