Several aspects of invasive round goby (Neogobius melanostomus) biology are based on sporadic observations or anecdotal reports only, e.g. they are night feeders, they prey on eggs and larvae of native fish and male feeding ceases or is highly restricted during breeding due to nest-guarding. To test the general validity of such hypotheses, we assessed diel and inter-sex differences in diet and feeding intensity of 232 gobies (144 female [54 day:90 night] and 88 male [39 day:49 night]) caught during the breeding season. Gobies took primarily aquatic insect larvae and did not predate on eggs, larvae or juveniles of native fish. Unlike previous studies, we observed no diel difference in feeding intensity or diet composition; hence no universal diel pattern can be implied for round goby feeding. On the other hand, we observed significant inter-sex differences in both feeding intensity and diet composition, with males consuming less food than females, presumably due to restricted feeding activity during nest-guarding. Inter-sex shifts in both diet composition and amount of food were less than expected, however, suggesting that, under most conditions, there is no reason to expect a fatal decrease in male energy intake, as suggested by some earlier studies.
Software measurements provide developers and software managers with information on various aspects of software systems, such as effectiveness, functionality, maintainability, or the effort and cost needed to develop a software system. Based on collected data, models capturing some aspects of software development process can be constructed. A good model should allow software professionals to not only evaluate current or completed projects but also predict future projects with an acceptable degree of accuracy.
Artificial neural networks employ a parallel distributed processing paradigm for learning of system and data behavior. Some network models, such as multilayer perceptrons, can be used to build models with universal approximation capabilities. This paper describes an application in which neural networks are used to capture the behavior of several sets of software development related data. The goal of the experiment is to gain an insight into the modeling of software data, and to evaluate the quality of available data sets and some existing conventional models.
The population structures of different species of Calliphoridae flies are highly diverse at different locations. We investigated populations of the Eastern European L. sericata using chaetotaxy and eight microsatellite loci. Our results strongly indicate that a panmictic population of L. sericata exists in the area studied, possibly with a high rate of intra-population gene flow. Analysis of chaetotaxy also supports the panmictic population hypothesis., Anna V. Diakova, Dmitry M. Schepetov, Nadezhda Y. Oyun, Anatole I. Shatalkin, Tatiana V. Galinskaya., and Obsahuje bibliografii
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.
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%).
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.
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.
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
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.