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2562. Assessing muscular oxygenation during incremental exercise using near-infrared spectroscopy: comparison of three different methods
- Creator:
- Agbangla, N. F., Audiffren, M., and Albinet, C. T.
- Type:
- article, model:article, and TEXT
- Subject:
- NIRS, muscle hemodynamics, linear slope, amplitude, and area under the curve
- Language:
- English
- Description:
- Using continuous-wave near-infrared spectroscopy (NIRS), this study compared three different methods, namely the slope method (SM), the amplitude method (AM), and the area under the curve (AUC) method to determine the variations of intramuscular oxygenation level as a function of workload. Ten right-handed subjects (22±4 years) performed one isometric contraction at each of three different workloads (30 %, 50 % and 90 % of maximal voluntary strength) during a period of twenty seconds. Changes in oxyhemoglobin (Δ[HbO2]) and deoxyhemoglobin (Δ[HHb]) concentrations in the superficial flexor of fingers were recorded using continuous-wave NIRS. The results showed a strong consistency between the three methods, with standardized Cronbach alphas of 0.87 for Δ[HHb] and 0.95 for Δ[HbO2]. No significant differences between the three methods were observed concerning Δ[HHb] as a function of workload. However, only the SM showed sufficient sensitivity to detect a significant decrease in Δ[HbO2] between 30 % and 50 % of workload (p<0.01). Among these three methods, the SM appeared to be the only method that was well adapted and sensitive enough to determine slight changes in Δ[HbO2]. Theoretical and methodological implications of these results are discussed.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
2563. Assessing spider community structure in a beech forest: Effects of sampling method
- Creator:
- Hövemeyer, Klaus and Stippich, Gabriele
- Type:
- article, model:article, and TEXT
- Subject:
- Aranae, sampling efficiency, catch compositon, beech forest, emergence traps, pitfall traps, soil samples, arboreal photo-eclectors, and ecological groups
- Language:
- English
- Description:
- The spider community of a beech forest on limestone was studied for one year using four sampling techniques: emergence traps, pitfall traps, soil samples, and arboreal eclectors. 87 spider species were recorded. Emergence traps and arboreal eclectors were particularly efficient in detecting spider species. Dominance identity (percentage similarity) was highest for catches from emergence traps and pitfall traps. Species recorded were assigned to various ecological groups. In terms of proportional abundance, representation of the ecological groups varied and appeared related to the sampling method used. Stratum type and type of prey capture strategy accounted for >60% of the variance in the catch results (canonical correspondence analysis). Proportional abundance of funnel-web spiders was much higher in pitfall trap catches (31.7%) than in any other method (1.0-11.6%).
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
2564. Assessing temporal variation and autocorrelation in fish habitat use
- Creator:
- Vilizzi, Lorenzo, Copp, Gordon H., and Roussel, Jean-Marc
- Type:
- article and TEXT
- Subject:
- PHABSIM, fish behaviour, individual-based models (IBMs), PCA, semi-variogram, log-linear analysis, and pseudoreplication
- Language:
- English
- Description:
- We assessed the xtent of temporal variation and autocorrelation in fish habitat use based on an experimental study of individual 0+ juvenile barbel, Barbus barbus, in an artificial flume. Five treated and five control fish were individually subjected to an increase in discharege (intervention) hlfway through each experiment and kept at baseline discharge throughout, respectively. Preference surves for velocity were generated for each of 60 trials per experiment and for each combination of treated/control (fish) x before/after-intervention. There were large between- and within-individual differences in velocity preference, both in treated and in control fish. Most barbel explored the entire range of velocities, whereas some individuals used a more limited range. Temporal variation in behavioural responses was assessed by a PCA-based methodology. Autocorrelation (i.e. correlation between sequential trials) was diagnosed in most response profiles, supporting recent fidings that individuals may have a "memory" of their past velocity usage. The relevance of the results for numerical habitat models of fish habitat assessment is discussed, as well as the importance of incorporating temporal variability into fish habitat use models (e.g. PHABSIM), not only as ontogenetic intervals but also as longitudinal data of individual behaviours. A warning is also re-issued about the erroneous belief of "pseudoreplication" simly arising from repeated measurements in time.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/
2565. Assessing the efficiency of using passive hair traps as a method for non-invasive sampling from European beavers (Castor fiber L.)
- Creator:
- Sobkowiak, Marta, Kochan, Joanna I., and Kruszyński, Wojciech
- Format:
- počítač and online zdroj
- Type:
- model:article and TEXT
- Subject:
- Castor sp., genetic monitoring, hair collecting, and DNA
- Language:
- English
- Description:
- Using passive hair traps to obtain genetic material from wild mammals is an effective form of testing the abundance of animal populations. Based on genetic analysis of collected hair, it is possible to estimate the number and sex of individuals present in a given area. The aim of this study was to confirm the success of the method of collecting hair from beavers in a non-invasive way, as well as to determine the effectiveness of using passive hair traps as sampling tools that can be applied in different regions. The study was carried out in the area of Stobrawa Landscape Park (southwestern Poland) between December 2017 and May 2018. For 17 control days, 12 samples were obtained, which gave the result of 0.7 samples per control day. This study shows that the proposed method, due to its simplicity and efficiency, could be a cost-effective way of collecting hair from free-ranging beavers without the need for capturing individuals.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
2566. Assessing the efficiency of UV LEDs as light sources for sampling the diversity of macro-moths (Lepidoptera)
- Creator:
- Infusino, Marco, Brehm, Gunnar, Di Marco, Carlo, and Scalercio, Stefano
- Format:
- print, počítač, and online zdroj
- Type:
- article, články, journal articles, model:article, and TEXT
- Subject:
- Zoologie, lesní ekosystémy, motýli, butterflies, forest ecosystems, Středozemní moře (oblast), Itálie, Mediterranean area, Italy, Lepidoptera, light trapping, UV LEDs, diversity, 2, and 59
- Language:
- English
- Description:
- Light trapping is the most widely used tool for determining the diversity of nocturnal Lepidoptera, but UV LEDs have yet to be used as light sources for the large-scale monitoring of Lepidoptera. We assessed the efficiency of this novel light source for sampling moths using a Heath type moth equipped with a strip of 150 high brightness UV LEDs (emission peak 398 nm, ~ 15 W) powered by a 12 V battery. We compared the number of individuals, the number of species and the Geometridae / Noctuidae ratio recorded for the samples collected using UV LED traps with those collected in two monitoring programs carried out in the same geographic region using two different light sources: a 200 W incandescent lamp (Rothamsted trap) and a 160 W mercury vapour lamp (manual catch). The total catch consisted of 61,120 individuals belonging to 699 species. The species richness rarefaction curves revealed that the Rothamsted trap collected fewer species and individuals than UV LED traps. Furthermore, the median numbers of species and individuals caught by UV LED traps fell within the range of those caught by mercury vapour lamp traps. In addition, the community composition recorded using incandescent lamps and UV LEDs was similar. The data obtained using UV LED traps, in absolute terms and in comparison with the other light sources and different sampling methods, clearly reveal that this light source is suitable for sampling macro-moth communities. For field work UV LEDs have many advantages, as they are resistant to mechanical damage, easily protected from heavy rain and energy efficient., Marco Infusino, Gunnar Brehm, Carlo Di Marco, Stefano Scalercio., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
2567. Assessing the evolution of learning capabilities and disorders with a graphical exploratory analysis of surveys containing missing and conflicting answers
- Creator:
- Sánchez , Luciano, Couso , Inés, Otero , José , and Palacios , Ana
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- Knowledge surveys, graphical exploratory analysis, multidimensional scaling, and fuzzy fitness-based genetic algorithms
- Language:
- English
- Description:
- The analysis of the evolution of learning with graphical maps is based on the placement of the individuals in positions that are computed on the basis of their answers to certain tests. These techniques are useful for detecting similarities between the knowledge profiles of the subjects and can also be used for assessing the acquisition of capabilities after a course. In this paper, we propose to extend some graphical exploratory analysis techniques to the case where there are missing or conflicting answers in the tests. We will also consider that either a missing or unknown answer, or a set of conflictive answers to a survey, is aptly represented by an interval or a fuzzy set. This representation causes that each individual in the map is no longer a point but a figure whose shape and size determine the coherence of the answers and whose position with respect to its neighbors determines the similarities and differences between the individuals.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
2568. Assessing the evolution of learning capabilities and disorders with a graphical exploratory analysis of surveys containing missing nd conflicting answers
- Creator:
- Sánchez-Monedero, J., Hervás-Martínez , C., Gutiérrez , P. A., Ruz, Mariano Carbonero , Ramírez Moreno , M. C. , and Cruz-Ramírez , M.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- Accuracy, differential evolution, extreme learning machine, multiclass classification, multiobjective, neural networks, and sensitivity
- Language:
- English
- Description:
- Accuracy alone can be deceptive when evaluating the performance of a classifier, especially if the problem involves a high number of classes. This paper proposes an approach used for dealing with multi-class problems, which tries to avoid this issue. The approach is based on the Extreme Learning Machine (ELM) classifier, which is trained by using a Differential Evolution (DE) algorithm. Two error measures (Accuracy, $C$, and Sensitivity, S) are combined and applied as a fitness function for the algorithm. The proposed approach is able to obtain multi-class classifiers with a high classification rate level in the global dataset with an acceptable level of accuracy for each class. This methodology is evaluated over seven benchmark classification problems and one real problem, obtaining promising results.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
2569. Assessment and identification of three types of difficult soils
- Creator:
- Ayadat, Tahar
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- identification, prediction, collapsible soil, swelling soil, liquefaction, and difficult soils
- Language:
- English
- Description:
- The soil engineer needs to be able to readily identify difficult or problematic soils and to determine the amount of settlement that may occur. This paper deals with the assessment and identification of three types of difficult soils: collapsible soils, swelling soils, and liquefiable soils. In the first instance, the study investigates the effect of some soil properties on wetting-induced collapse strain and the swelling potential of soils. Also, two new methods for predicting soil collapse and swelling potential are developed. The proposed relationships correlate between collapse strain and swelling potential and some soil parameters which are believed to govern soil collapse and swelling. Validation of these two relationships with some data reported in literature is also examined. Furthermore, the paper describes the different steps suggested in a new procedure for soil liquefaction assessment. The procedure was presented in the form of an evaluation guide. In addition, a relationship was suggested for computing the potential for liquefaction. An application of the proposed procedure to a practical case is included in order to validate and illustrate the different steps to be followed in the suggested evaluation procedure.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
2570. Assessment of brown adipose tissue activity in rats by 99mTc-sestamibi uptake
- Creator:
- Kyparos, D., Arsos, G., Georga, S., Petridou , A., Kyparos , A. , Papageorgiou , E., Mougios, V., Matziari, C., and Karakatsanis, C.
- Type:
- article, model:article, and TEXT
- Subject:
- Brown adipose tissue, 99m Tc-sestamibi, Mitochondria, Allometry, and Imaging
- Language:
- English
- Description:
- Brown adipose tissue (BAT) physiology and imaging have recently attracted considerable attention. BAT is characterized both by enhanced perfusio n and increased mitochondrial activity. 99mTc-sestamibi is a lipophilic cationic tracer that concentrates in mitochondria. Data on the accumulation of 99mTc-sestamibi in BAT are currently lacking. This study investigates the in vivo99mTc-sestamibi uptake in rat BAT. 99mTc-sestamibi was administered in male Wistar rats of various age and body size. 99mTc-sestamibi uptake was measured in vitro in BAT and white fat (WF) together with cytochrome c oxidase activity. Both 99mTc-sestamibi uptake and cytochrome c oxidase activity were higher in BAT than in WF (P<0.05). 99m Tc-Sestamibi uptake in both BAT and WF was negatively related to body weight (r= -0.96 and -0.89, respectively) as was the BAT/WF uptake ratio (r = -0.85). These data show a higher 99mTc-sestamibi uptake in BAT compared to WF, in agreement with the high mitochondrial content and respiratory activity of the former. The strong negative correlation between 99mTc-sestamibi uptake in BAT and body weight (negative allometry), is in accordance to increased needs of thermogenesis in smaller animals. Implications of increased 99mTc-sestamibi uptake in BAT in radionuclide imaging are also discussed.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public