Through a barn owl’s eyes: interactions between scene content and visual attention

In this study we investigated visual attention properties of freely behaving barn owls, using a miniature wireless camera attached to their heads. The tubular eye structure of barn owls makes them ideal subjects for this research since it limits their eye movements. Video sequences recorded from the owl’s point of view capture part of the visual scene as seen by the owl. Automated analysis of video sequences revealed that during an active search task, owls repeatedly and consistently direct their gaze in a way that brings objects of interest to a specific retinal location (retinal fixation area). Using a projective model that captures the geometry between the eye and the camera, we recovered the corresponding location in the recorded images (image fixation area). Recording in various types of environments (aviary, office, outdoors) revealed significant statistical differences of low level image properties at the image fixation area compared to values extracted at random image patches. These differences are in agreement with results obtained in primates in similar studies. To investigate the role of saliency and its contribution to drawing the owl’s attention, we used a popular bottom-up computational model. Saliency values at the image fixation area were typically greater than at random patches, yet were only 20% out of the maximal saliency value, suggesting a top-down modulation of gaze control.     

The synthesis and use of the owl’s auditory space map

The barn owl (Tyto alba) is capable of capturing prey by passive hearing alone, guided by a topographic map of auditory space in the external nucleus of its inferior colliculus. The neurons of this auditory space map have discrete spatial receptive fields that result from the computation of interaural differences in the level (ILD) and time-of-arrival (ITD) of sounds. Below we review the synthesis of the spatial receptive fields from the frequency-specific ITDs and ILDs to which the neurons are tuned, concentrating on recent studies exploiting virtual auditory space techniques to analyze the contribution of ILD. We then compared the owls spatial discrimination, assessed behaviorally, with that of its space map neurons. Spatial discrimination was assessed using a novel paradigm involving the pupillary dilation response (PDR), and neuronal acuity was assessed by measuring the changes in firing rate resulting from changes in source location, scaled to the variance. This signal-detection-based approach revealed that the change in the position of the neural image on this map best explains the spatial discrimination measured using the PDR. We compare this result to recent studies in mammalian systems.     

Influence of nitrogen on the production of hypericins by St. John’s wort

The effect of nitrogen supply on the production of ‘hypericins’ (hypericin and pseudohypericin) in leaves of St. John’s wort (Hypericum perforatum L.) was examined with plants grown in sand culture and soil. In sand culture, 56-d growth of St. John’s wort plants with decreased nitrogen levels resulted in increased production of hypericins in leaves. A short-term low nitrogen stress in sand culture also resulted in increased production of leaf hypericins. While growth in a low nitrogen-containing soil resulted in elevated levels of hypericins, their production was decreased by supplementation of the soil with additional nitrogen. Increased production of hypericins in St. John’s wort leaves did not require the nitrogen supply to be decreased to levels that resulted in nitrogen deficiency symptoms. Moreover, alteration in the production of leaf hypericins occurring with changes in nitrogen supply did not alter the concentration ratio of pseudohypericin and hypericin. Increased production of leaf hypericins was not associated with any significant changes in the number of dark glands on the leaves and only a weak correlation was observed between leaf dark gland number and levels of leaf hypericins. These results are discussed in terms of the biochemistry of naphthodianthrone production by St. John’s wort plants and implications for growth environment effects during cultivated growth of this medicinal plant.     

Influence of livestock grazing on the capybara’s trophic niche and forage preferences

Trophic niche parameters and forage preferences of capybaraHydrochaeris hydrochaeris Linnaeus, 1766 were studied at three areas of east-central Argentina: Lower Delta Islands (LDI), only capybara present; Puerto Constanza (PC), capybara and cattle, and Villaguay (VI), capybara, cattle and sheep. Significant correlation was found in the annual botanical composition of capybara faeces at LDI and PC, but no correlation was found between faecal composition at these two areas and those at VI. The narrowest trophic niche corresponded to LDI, while the widest corresponded to VI, with significant differences in the values among the three areas. Capybara consumedCarex riparia, Cynodon dactylon andPanicum grumosum in LDI, andP. milioides in VI in proportion greater than availability. Three and eight food items were consumed less than availability in VI and PC, respectively. The greater the species number and density of livestock animals, the more generalist the behavior of capybara, possibly due to direct interaction in the use of grazing resources. Changes in availability of foraging species may influence the capybara’s preference patterns and the consumption of suboptimal feeding items may indicate a greater pressure on foraging resources in the areas where capybaras share their habitat with livestock.     

Study on dynamic characteristics’ change of hippocampal neuron reduced models caused by the Alzheimer’s disease

In the paper, based on the electrophysiological experimental data, the Hippocampal neuron reduced model under the pathology condition of Alzheimer’s disease (AD) has been built by modifying parameters’ values. The reduced neuron model’s dynamic characteristics under effect of AD are comparatively studied. Under direct current stimulation, compared with the normal neuron model, the AD neuron model’s dynamic characteristics have obviously been changed. The neuron model under the AD condition undergoes supercritical Andronov–Hopf bifurcation from the rest state to the continuous discharge state. It is different from the neuron model under the normal condition, which undergoes saddle-node bifurcation. So, the neuron model changes into a resonator with monostable state from an integrator with bistable state under AD’s action. The research reveals the neuron model’s dynamic characteristics’ changing under effect of AD, and provides some theoretic basis for AD research by neurodynamics theory.     

Influence of the electron density on the characteristics of terahertz waves generated under laser–cluster interaction

A theory of generation of terahertz radiation under laser–cluster interaction, developed earlier for an overdense cluster plasma [A. A. Frolov, Plasma Phys. Rep. 42. 637 (2016)], is generalized for the case of arbitrary electron density. The spectral composition of radiation is shown to substantially depend on the density of free electrons in the cluster. For an underdense cluster plasma, there is a sharp peak in the terahertz spectrum at the frequency of the quadrupole mode of a plasma sphere. As the electron density increases to supercritical values, this spectral line vanishes and a broad maximum at the frequency comparable with the reciprocal of the laser pulse duration appears in the spectrum. The dependence of the total energy of terahertz radiation on the density of free electrons is analyzed. The radiation yield is shown to increase significantly under resonance conditions, when the laser frequency is close to the eigenfrequency of the dipole or quadrupole mode of a plasma sphere.     

The role of Apodemus mice and Microtus voles in the diet of the Tengmalm’s owl in Central Europe

Based on a long-term dataset (1999–2010), we investigated how the availability of main prey affects the breeding density and food ecology of the Tengmalm’s owl (Aegolius funereus) in the Czech Republic. In particular, we assessed the role of Microtus voles and Apodemus mice in the diet, based on the main predictions of the optimal diet theory that the diet composition depends on the availability of the main prey. We found that (i) the Tengmalm’s owl exhibited no numerical response to the availability of Microtus voles and Apodemus mice in the field; (ii) the availability of Apodemus mice in the field positively affected their proportion in the diet (26 %), and despite a high proportion of Microtus voles in the owls’ diet (47 %), no relationship was found between their availability in the field and proportion in the diet; (iii) the proportion of Apodemus mice was negatively correlated to the proportion of Microtus voles, Sorex shrews and birds in the diet, but no similar relationship was detected for Microtus voles; (iv) the reproductive output of Tengmalm’s owls was positively correlated to the proportion of Apodemus mice in the diet, as well as to Apodemus mice and Microtus vole availability in the field; and (v) diet diversity and diet overlap were not significantly affected by the abundance of Apodemus mice and Microtus voles. Therefore, the validity of these main optimal diet theory predictions was not confirmed, especially for Microtus vole prey, due to an opportunistic choice between Apodemus mice and Microtus voles. We suggest that the reproductive output of nocturnal raptors in Central Europe may be less dependent on Microtus vole supply than that of their northern counterparts.     

Parental Perception of Weight Status: Influence on Children’s Diet in the Gateshead Millennium Study

Objective

Recognising overweight and obesity is critical to prompting action, and consequently preventing and treating obesity. The present study examined the association between parental perceptions of child weight status and child’s diet.

Methods

Participants were members of the Gateshead Millennium Study. Parental perception of their child’s weight status was assessed using a questionnaire and compared against International Obesity Task Force cut-offs for childhood overweight and obesity when the children were aged 6–8 years old. Diet was assessed at age 6-8years old using the FAST (Food Assessment in Schools Tool) food diary method. The association between parental perception and dietary patterns as defined by Principal Components Analysis, was assessed using multivariate regression after adjustment for child’s gender, child’s weight status, maternal body mass index (BMI), maternal education and deprivation status.

Results

Of the 361 parents who provided complete data on confounders and on their perception of their child’s weight status, 63 (17%) parents perceived their child as being of ‘normal’ weight or ‘overweight’ when they were actually ‘overweight’ or ‘obese’, respectively. After adjustment for confounders, parents who misperceived their child’s weight had children with a lower ‘healthy’ dietary pattern score compared to children whose parents correctly perceived their weight (β = -0.88; 95% CI: -1.7, -0.1; P-value = 0.028). This association was found despite higher consumption of reduced sugar carbonated drinks amongst children whose parents incorrectly perceived their weight status compared to children whose parents perceived their weight correctly (52.4% vs. 33.6%; P-value = 0.005).

Conclusions

In conclusion, children whose parents did not correctly perceive their weight status scored lower on the ‘healthy’ dietary pattern. Further research is required to define parents’ diets based on their perception status and to examine if a child’s or parent’s diet mediates the association between parental perception and child weight.     

High interannual variation in the hatching sex ratio of Tengmalm’s owl broods during a vole cycle

The sex ratio at hatching in broods of Tengmalms owl (Aegolius funereus) in northern Sweden was investigated for 3 years characterized by different phases of the vole and owl cycle. Previous work showed the sex ratio in this species to be male-biased for 1 year with a favourable food supply, and that in feeding experiments male nestlings (but not females) suffered higher mortality when food was limited, but not otherwise. Here we present data from a complete 3-year owl cycle, showing that mean brood sex ratio varied significantly among years, being male-biased (65% males) in the first year of high owl breeding density, unbiased (49%) in the second year of high owl breeding density, and female-biased (33% males) in the owls low year. Brood sex ratio did not vary significantly within years with laying date or parental age. Vole availability, and therefore the owls food supply, declined during the 3 years studied. Tengmalms owl parents thus appear to adaptively adjust the sex ratio of their broods according to the expected annual mortality risk of sons.     

A Spotlight on Preschool: The Influence of Family Factors on Children’s Early Literacy Skills

Rationale

Phonological awareness, letter knowledge, oral language (including sentence recall) and rapid automatised naming are acknowledged within-child predictors of literacy development. Separate research has identified family factors including socio-economic status, parents’ level of education and family history. However, both approaches have left unexplained significant amounts of variance in literacy outcomes. This longitudinal study sought to improve prospective classification accuracy for young children at risk of literacy failure by adding two new family measures (parents’ phonological awareness and parents’ perceived self-efficacy), and then combining the within-child and family factors.

Method

Pre-literacy skills were measured in 102 four year olds (46 girls and 56 boys) at the beginning of Preschool, and then at the beginning and end of Kindergarten, when rapid automatised naming was also measured. Family factors data were collected at the beginning of Preschool, and children’s literacy outcomes were measured at the end of Year 1 (age 6–7 years).

Results

Children from high-risk backgrounds showed poorer literacy outcomes than low-risk students, though three family factors (school socio-economic status, parents’ phonological awareness, and family history) typically accounted for less Year 1 variance than the within-child factors. Combining these family factors with the end of Kindergarten within-child factors provided the most accurate classification (i.e., sensitivity = .85; specificity = .90; overall correct = .88).

Implications

Our approach would identify at-risk children for intervention before they began to fail. Moreover, it would be cost-effective because although few at-risk children would be missed, allocation of unnecessary educational resources would be minimised.     

Effects of industrial storage on the bioreduction capacity of brewer’s yeast

The effects of industrial storage on the changes of the cell viability and the activities of intracellular alcohol dehydrogenase (ADH) and glucose-6-phosphate dehydrogenase (G6PDH) in brewer’s yeast, and the corresponding capacity for the bioconversion of ethyl-3-oxobutanoate (EOB) to ethyl (S)-3-hydroxybutanoate ((S)-EHB), were investigated. The viability of fresh brewer’s yeast cells stored in industrial circulating cooling water at 1–2°C showed 4 and 15% drop after the storage of 7 and 15 days, respectively, after which cells died rapidly. The pretreatment of the stored brewer’s yeast cells by washing and screening significantly enhanced cell viability during industrial storage. The intracellular levels of ADH and G6PDH after permeabilization of these stored cells with cetyltrimetylammonium bromide (CTAB) were much higher, which showed only slight decrease within 2 weeks during the industrial storage. When the stored cells after the permeabilization treatment was used as the biocatalyst at 90–120 g/L, EOB was converted almost completely into enantiopure (S)-EHB with an enantiomeric excess (ee) more than 99% and a yield of over 96%, by fed-batch bioconversion of 560 mM EOB within 6 h. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.     

Unintended Effects of Cardiovascular Drugs on the Pathogenesis of Alzheimer’s Disease

Alzheimer’s disease (AD) is rapidly becoming one of the leading causes of disability and mortality in the elderly. As life-expectancy increases, an increasing number of people will rely on modern medicines to treat age-associated disorders. Among these medications, some might benefit, while others might exacerbate, the pathogenesis of AD. We screened 1,600 FDA approved drugs for β-amyloid (Aβ)-modifying activity and identified drugs that can potentially influence amyloid precursor protein processing. In this study, we focused on cardiovascular drugs and demonstrated that some hypertensive medication can differentially modulate Aβ, both in vitro and in vivo. Our study suggests that some commonly prescribed drugs might exert unintended effects and modulate AD and provides the basis for continuing investigation of the role of individual drugs on a case-by-case basis. This line of investigation will lead to the identification of common medications that are potentially beneficial or detrimental to AD as a reference for physicians to consider when prescribing the most appropriate drugs for their patients, particularly for treating chronic disorders among the growing geriatric population.     

Influence of Blue-Light Signaling Components on the Regulation of Cytokinin-Dependent Arabidopsis thaliana Seedlings’ Greening

Russian Journal of Plant Physiology - De-etiolation of plant seedlings is controlled by a complex system of light and hormonal signaling. This process is accompanied by chloroplast development and...     

Influence of Macroelements’ Uneven Distribution on the Content of Hormones and Extension of the Roots in Wheat Plants

Russian Journal of Plant Physiology - Increase in the level of mineral nutrition reduces the relative growth rate of the roots, which adversely affects the drought resistance of plants. This was...     

Changes in sleep characteristics of rat preclinical model of Parkinson’s disease based on attenuation of the ubiquitin—proteasome system activity in the brain

Numerous experimental and epidemiological data indicate a high significance of environmental neurotoxins, specifically, inhibitors of the ubiquitin–proteasome system, in pathogenesis of Parkinson’s disease (PD). To develop a preclinical model of PD in rats we used a technique of intranasal administration of lactacystin, a natural proteasome inhibitor, into the brain. It was found that three weeks after the first lactacystin administration it induced a little degeneration of dopaminergic neurons in the olfactory bulb and substantia nigra pars compacta without any olfactory dysfunction and motor behavior disorders. Besides, its effect led to the appearance of some signs of sleep disorders: increased somnolence (especially in the dark, active daily phase), fragmentation of slow-wave sleep, decreased EEG delta rhythm during slow-wave sleep. These signs share some similarity with PD and could be useful in clinical studies for the quick search for polysomnographic markers of the early PD stage.     

Influence of Incubation Conditions on Hydrolysis Efficiency and Iodine Enrichment in Baker’s Yeast

The influence of incubation conditions, enzyme type, hydrolysis time, and potassium iodide concentration on hydrolysis and iodine enrichment were studied in supernatant and pellets of Saccharomyces cervisiae hydrolysates. The type of enzyme used and incubation time significantly influence hydrolysis efficiency and protein concentration in supernatant and pellet. The highest protein hydrolysis efficiency was obtained by 24-h incubation with papain. Significantly lower values were observed for pepsin and autolysis. The potassium iodide concentration influences the iodine content of supernatant and pellet, but not hydrolysis. Iodide enrichment of supernatant and pellet depends on the concentration of iodide using during incubation. High concentration of iodide and long incubation times were the conditions for optimal iodide enrichment and high-protein hydrolysates. The optimal hydrolysis efficiency and iodine enrichment were obtained during 24-h incubation with papain in a 4.5-mM potassium iodide medium. The efficiency reached 98.22% with iodine concentrations of 2,664.91 and 9,200.67 μg/g iodine in pellet and supernatant, respectively.     

Influence of Prohexadione-Calcium on the Growth and Quality of Summer ‘Jen-Ju Bar’ Guava Fruit

A 2-year trial was conducted to investigate the influence of prohexadione-calcium (ProCa) on the fruit quality of summer ‘Jen-Ju Bar’ guava (Psidium guajava L.). ‘Jen-Ju Bar’ trees were treated with various concentrations of ProCa: 0 (as control), 125, 250, and 500 mg L^?1, which significantly inhibited spring shoot growth. Summer guava fruits of the trees subjected to ProCa exhibited higher levels of total soluble solids and higher values of total soluble solids to titratable acidity ratio compared with control fruits. Summer guava fruits from trees treated with ProCa were firmer than those from untreated trees. ProCa sprays significantly affected pulp weight, core weight, pulp thickness, and pulp-to-core ratio. No other fruit quality characteristics were significantly affected by ProCa treatment.     

Composition of the body mass overshoot in European barn owl nestlings (Tyto alba ): insurance against scarcity of energy or water?

European barn owl chicks (Tyto alba) show a body mass overshoot prior to fledging that has been predicted to serve as an energy reservoir during periods of stochastic food availability. However, the composition of the mass overshoot has heretofore not been directly examined in nestlings of this or any other species displaying a body mass overshoot during growth (e.g., raptors and seabirds). To experimentally determine whether the overshoot in body mass in juvenile European barn owls (Tyto alba) may act as an energy reservoir, we compared the body composition of owl chicks raised on an ad libitum diet to those fed a restricted diet designed to eliminate the overshoot. Chicks raised on the two diets were also compared for differences in maturation of diverse functions (e.g., locomotion) and tissues (e.g., skeletal development). Contrary to expectations, our results on body composition in juvenile barn owls indicate that the mass overshoot prior to fledging is primarily comprised of an increased water compartment. Thus, we suggest that the mass overshoot in owls (and possibly in other species) does not serve as an energy reservoir but, rather, may function as an insurance against dehydration when hot in-nest conditions force chicks to rely on evaporative cooling: temperatures in barn owl nests can reach up to 43 degrees C. We found no significant differences in maturation indexes between diet treatments at the time of fledging.     

Exploring Children’s Perspectives on the Welfare Needs of Pet Animals

Children are increasingly viewed as important recipients of educational interventions to improve animal welfare, yet research examining their perspectives is lacking, particularly within the UK. Helping children to care appropriately for animals depends, not least, on an ability to understand the needs of different species and correctly identify cues given by the animal that indicate its welfare state. This study began to explore: (a) children’s perceptions of welfare needs, focusing on four common pet animals; (b) influences on the development of knowledge; (c) beliefs about whether or not (all) animals are sentient, and (d) their confidence in identifying when their own pets are in need. Fourteen focus groups were carried out with 53 children aged 7 to 13 years. Findings highlighted an affirmative response that animals have feelings (dogs especially), albeit with doubts about this applying universally. There was wide variation in children’s knowledge of welfare needs, even among owners of the animal in question. Conversely, some children lacked confidence in spite of the extensive knowledge they had developed through direct experience. An important finding was a perceived difficulty in identifying the needs of particular species or specific types of need in their own pets. Fitting well with a recent emphasis on “positive welfare,” children felt that many animals need demonstrative love and attention, especially cats and dogs. While there is clearly scope for educating children about common needs and cues that indicate animals’ welfare state, other areas pose a greater challenge. Emotional connection seems important in the development of extensive knowledge and concern for welfare. Accordingly, animals that do not possess the kind of behavioral repertoire that is easy to interpret or allows for a perceived sense of reciprocity are possibly at risk of negative welfare experiences.