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Mature sunflower (Helianthus annuus) inflorescences, which no longer follow the Sun, face the eastern celestial hemisphere. Whether they orient toward the azimuth of local sunrise or the geographical east? It was recently shown that they absorb maximum light energy if they face almost exactly the geographical east, and afternoons are usually cloudier than mornings. However, the exact average and standard deviation (SD) of the azimuth angle of the normal vector of mature sunflower inflorescences have never been measured on numerous individuals. It is imaginable that they prefer the direction of sunrise rather than that of the geographical east. To decide between these two photobiological possibilities, we photographed mature inflorescences of 14 sunflower plantations using a drone and determined the average and SD of the azimuth angle of the normal vector of 2,800 sunflower heads. We found that the average azimuth αinflorescence = 89.5° ± 42.8° (measured clockwise from the geographical north) of inflorescences practically coincided with the geographical eastern direction (αeast = 90°) instead of the azimuth of local sunrise αsunrise = 56.14° – 57.55°. Although the SD of the orientation of individual inflorescences was large (± 42.8°), our finding experimentally corroborated the earlier theoretical prediction that the energetically ideal azimuth of sunflower inflorescences is east, if mornings are usually less cloudy than afternoons, which is typical for the domestication region of H. annuus. However, the average orientation of inflorescences of two plantations in hilly landscapes more or less differed from that of the majority of plantations in plane landscapes. The reason for this deviation may be that the illumination conditions in hilly sites more or less differed from those in plane landscapes. Furthermore, in a plantation, we observed a group of south-facing inflorescences that were in shadow for about 5 h both after sunrise and before sunset. This southern orientation can be explained by the southern maximum of total light energy absorbed by the partly shadowed inflorescences during the day, as computed by our software integrating both the diffuse skylight and the direct sunlight received by sunflower inflorescences.

Symmetry analysis can provide a suitable change of variables, i.e., in geometric terms, a suitable diffeomorphism that simplifies the given direction field, which can help significantly in solving or studying differential equations. Roughly speaking this is the so-called rectification theorem. The local version of this result is a well-known theorem in the field of ordinary differential equations. In this note we prove a global counterpart when the equation fulfils the Lipschitz condition. Then we use this result to determine the global symmetry group of such an ordinary differential equation. It turns out that, assuming the Lipschitz condition, the full symmetry group is a smooth wreath product of two diffeomorphism groups, and does not depend on the form of the equation, at all., Comment: To appear in Journal of Lie Theory

The treatment of hepatitis C is based on a national consensus guideline updated six-monthly according to local availability and affordability of approved therapies through a transparent allocation system in Hungary. This updated guideline incorporates some special new aspects, including recommendations for screening, diagnostics, use and allocation of novel direct acting antiviral agents. The indication of therapy in patients with no contraindication is based on the demonstration of viral replication with consequent inflammation and/or fibrosis in the liver. Non-invasive methods (elastographies and biochemical methods) are preferred for liver fibrosis staging. The budget allocated for these patients is limited. Interferon-based or interferon-free therapies are available for the treatment. Due to their limited success rate as well as to their (sometimes severe) side-effects, the mandatory use of interferon-based therapies as first line treatment can not be accepted from the professional point of view. However, they can be used as optional therapy in treatment-naïve patients with mild disease. As of interferon-free therapies, priority is given to those with urgent need based on a pre-defined scoring system reflecting mainly the stage of the liver disease, but considering also additional factors, i.e., hepatic decompensation, other complications, activity and progression of liver disease, risk of transmission and other special issues. Approved treatments are restricted to the most cost-effective combinations based on the cost per sustained virological response value in different patient categories with consensus amongst treating physicians, the National Health Insurance Fund of Hungary and patients’ organizations. Interferon-free treatments and shorter therapy durations are preferred. Orv Hetil. 2018; 159(Suppl 1): 3–23.

The moon illusion is a visual deception when people perceive the angular diameter of the Moon/Sun near the horizon larger than that of the one higher in the sky. Some theories have been proposed to explain this illusion, but not any is generally accepted. Although several psychophysical experiments have been performed to study different aspects of the moon illusion, their results have sometimes contradicted each other. Artists frequently display(ed) the Moon/Sun in their paintings. If the Moon/Sun appears near the horizon, its painted disc is often exaggeratedly large. How great is the magnitude of moon illusion of painters? How different are the size enlargements of depicted lunar/solar discs? To answer these questions, we measured these magnitudes on 100 paintings collected from the period of 1534–2017. In psychophysical experiments, we also investigated the moon illusion of 10 test persons who had to estimate the size of the lunar/solar disc on 100 paintings and 100 landscape photographs from which the Moon/Sun was retouched. Compared to the lunar/solar disc calculated from reference distances estimated by test persons in paintings, painters overestimated the Moon's size on average Q = 2.1 ± 1.6 times, while the Sun was painted Q = 1.8 ± 1.2 times larger than the real one, where Q = rpainted/rreal is the ratio of the radii of painted (rpainted) and real (rreal) Moons/Suns. In landscape photos, test persons overestimated the Moon's size Q = 1.6 ± 0.4 times and the Sun was assumed Q = 1.7 ± 0.5 times larger than in reality, where Q = rtest/rreal is the ratio of the radius rtest estimated by the test persons and the real radius rreal of Moons/Suns. The majority of the magnitude of moon illusion Q = 1.6, 1.6, 1.7, 1.8, 2.1, 2.8, 2.9 measured by us are larger than the Q-values 1.1, 1.2, 1.3, 1.4, 1.5, 1.6, 1.8 obtained in previous psychophysical experiments due to methodological differences.

Tabanid flies (Diptera: Tabanidae) are attracted to shiny black targets, prefer warmer hosts against colder ones and generally attack them in sunshine. Horizontally polarised light reflected from surfaces means water for water-seeking male and female tabanids. A shiny black target above the ground, reflecting light with high degrees and various directions of linear polarisation is recognised as a host animal by female tabanids seeking for blood. Since the body of host animals has differently oriented surface parts, the following question arises: How does the attractiveness of a tilted shiny black surface to male and female tabanids depend on the tilt angle δ? Another question relates to the reaction of horseflies to horizontal black test surfaces with respect to their surface temperature. Solar panels, for example, can induce horizontally polarised light and can reach temperatures above 55 °C. How long times would horseflies stay on such hot solar panels? The answer of these questions is important not only in tabanid control, but also in the reduction of polarised light pollution caused by solar panels. To study these questions,we performed field experiments inHungary in the summer of 2019 with horseflies and black sticky and dry test surfaces. We found that the total number of trapped (male and female) tabanids is highest if the surface is horizontal (δ = 0°), and it is minimal at δ = 75°. The number of trapped males decreases monotonously to zero with increasing δ, while the female catch has a primary maximum and minimum at δ=0° and δ = 75°, respectively, and a further secondary peak at δ = 90°. Both sexes are strongly attracted to nearly horizontal (0° ≤ δ ≤ 15°) surfaces, and the vertical surface is also very attractive but only for females. The numbers of touchdowns and landings of tabanids are practically independent of the surface temperature T. The time period of tabanids spent on the shiny black horizontal surface decreases with increasing Tso that above 58 °C tabanids spent no longer than 1 s on the surface. The horizontally polarised light reflected fromsolar panels attracts aquatic insects. This attraction is adverse, if the lured insects lay their eggs onto the black surface and/or cannot escape from the polarised signal and perish due to dehydration. Using polarotactic horseflies as indicator insects in our field experiment, we determined the magnitude of polarised light pollution (being proportional to the visual attractiveness to tabanids) of smooth black oblique surfaces as functions of δ and T.

Many insect species rely on the polarization properties of object-reflected light for vital tasks like water or host detection. Unfortunately, typical glass-encapsulated photovoltaic modules, which are expected to cover increasingly large surfaces in the coming years, inadvertently attract various species of water-seeking aquatic insects by the horizontally polarized light they reflect. Such polarized light pollution can be extremely harmful to the entomofauna if polarotactic aquatic insects are trapped by this attractive light signal and perish before reproduction, or if they lay their eggs in unsuitable locations. Textured photovoltaic cover layers are usually engineered to maximize sunlight-harvesting, without taking into consideration their impact on polarized light pollution. The goal of the present study is therefore to experimentally and computationally assess the influence of the cover layer topography on polarized light pollution. By conducting field experiments with polarotactic horseflies (Diptera: Tabanidae) and a mayfly species (Ephemeroptera:Ephemera danica), we demonstrate that bioreplicated cover layers (here obtained by directly copying the surface microtexture of rose petals) were almost unattractive to these species, which is indicative of reduced polarized light pollution. Relative to a planar cover layer, we find that, for the examined aquatic species, the bioreplicated texture can greatly reduce the numbers of landings. This observation is further analyzed and explained by means of imaging polarimetry and ray-tracing simulations. The results pave the way to novel photovoltaic cover layers, the interface of which can be designed to improve sunlight conversion efficiency while minimizing their detrimental influence on the ecology and conservation of polarotactic aquatic insects.

Since the discovery in 1772 of the triangular Lagrange points L4 and L5 in the gravitational field of two bodies moving under the sole influence of mutual gravitational forces, astronomers found a large number of minor celestial bodies around these points of the Sun-Jupiter, Sun-Earth, Sun-Mars and Sun-Neptune systems. The L4 and L5 points of the Earth and Moon may be empty due to the gravitational perturbation of the Sun. However, in 1961 Kordylewski found two bright patches near the L5 point, which may refer to an accumulation of interplanetary particles. Since that time this formation is called the Kordylewski dust cloud (KDC). Until now only a very few computer simulations studied the formation and characteristics of the KDC. To fill this gap, we investigated a three-dimensional four-body problem consisting of the Sun, Earth, Moon and one test particle, 1860000 times separately. We mapped the size and shape of the conglomeratum of particles not escaped from the system sooner than an integration time of 3650 days around L5. Polarimetric observations of a possible KDC around L5 are presented in the second part of this paper.

Calibration of the Thermocamera + Supplementary Results (Reflection-polarization characteristics of the warm and cold barrels, Thermal characteristics of the warm and cold barrels, Schlieren imagery of the warm/cold air next to the warm/cold barrels, Attractiveness of the warm and cold barrels to tabanids) + Supplementary Tables S1, S2, S3 + Supplementary Figures S1, S2, S3, S4

Data of samples used in this study and relevant molecular data. The flea species are ordered vertically according to their taxonomic relationships (i.e. representing Pulicidae, Vermipsyllidae, Leptopsyllidae and Ceratophyllidae). (DOCX 25 kb)

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Bodypainting is widespread in African, Australian and Papua New Guinean indigenous communities. Many bodypaintings use white or bright yellow/grey/beige stripes on brown skin. Where the majority of people using bodypainting presently live, blood-sucking horseflies are abundant, and they frequently attack the naked brown regions of the human body surface with the risk of transmitting the pathogens of dangerous diseases. Since horseflies are deterred by the black and white stripes of zebras, we hypothesized that white-striped paintings on dark brown human bodies have a similar effect. In a field experiment in Hungary, we tested this hypothesis. We show that the attractiveness to horseflies of a dark brown human body model significantly decreases, if it is painted with the white stripes that are used in bodypaintings. Our brown human model was 10 times more attractive to horseflies than the white-striped brown model, and a beige model, which was used as a control, attracted two times more horseflies than the striped brown model. Thus, white-striped bodypaintings, such as those used by African and Australian people, may serve to deter horseflies, which is an advantageous byproduct of these bodypaintings that could lead to reduced irritation and disease transmission by these blood-sucking insects.

According to a famous hypothesis, Viking sailors could navigate along the latitude between Norway and Greenland by means of sky polarization in cloudy weather using a sun compass and sunstone crystals. Using data measured in earlier atmospheric optical and psychophysical experiments, here we determine the success rate of this sky-polarimetric Viking navigation. Simulating 1000 voyages between Norway and Greenland with varying cloudiness at summer solstice and spring equinox, we revealed the chance Viking sailors could reach Greenland under the varying weather conditions of a 3-week-long journey as a function of the navigation periodicity Δt if they analysed sky polarization with calcite, cordierite or tourmaline sunstones. Examples of voyage routes are also presented. Our results show that the sky-polarimetric navigation is surprisingly successful on both days of the spring equinox and summer solstice even under cloudy conditions if the navigator determined the north direction periodically at least once in every 3 h, independently of the type of sunstone used for the analysis of sky polarization. This explains why the Vikings could rule the Atlantic Ocean for 300 years and could reach North America without a magnetic compass. Our findings suggest that it is not only the navigation periodicity in itself that is important for higher navigation success rates, but also the distribution of times when the navigation procedure carried out is as symmetrical as possible with respect to the time point of real noon.

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We consider a PH/PH/1 queue in which a threshold policy determines the stage of the system. The arrival and service processes follow a Phase-Type (PH) distribution depending on the stage of the system. Each stage has both a lower and an upper threshold at which the stage of the system changes, and a new stage is chosen according to a prescribed distribution. The PH/PH/1 multi-threshold queue is a Quasi-Birth-and-Death process with a tri-diagonal block structured boundary state which we model as a Level Dependent Quasi-Birth-and-Death process. An efficient algorithm is presented to obtain the stationary queue length vectors using Matrix Analytic methods.

Matrix Inversion Tomosynthesis (MITS) is a linear MIMO system, which deblurs Shift And Add (SAA) reconstructed tomosynthesis slices by applying deconvolution in spectral domain. When implementing MITS, some difficulties, important from both theoretical and practical viewpoints should be considered. In this paper new combined methods are proposed to tackle one of them, the truncation artifact caused by spectral leakage in thoracic imaging using DTS. The effect of the proposed methods is illustrated by coronal human chest slices, validated and compared quantitatively.

Electronic Supplementary Material

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The high ratio of loans over 90 days past due, i.e. nonperforming mortgage loans, is the legacy of the crisis and the excessive lending that preceded it. The volume has continuously grown over the past six years and by the end of 2014 accounted for one quarter of the total mortgage portfolio, affecting approximately 140,000 debtors. The degree of exposure within the entire system of financial intermediation is nearly HUF 1,450 billion, nearly 5 per cent of GDP. Terminated contracts now account for over half of the total portfolio, which may essentially lead to execution and thus the loss of the property for debtors. As a result, this is currently one of the most pressing issues for financial stability and a major social risk in Hungary. A deep analysis and broad understanding of the issue is indispensable for finding the proper solution. Despite the importance of the matter, we know little about nonperforming mortgage loans. This study aims to provide a comprehensive picture of the attributes of these loans after settlement and forint conversion on the basis of individual data. The data clearly show that the heart of the matter in terms of both wealth and income is the excessive level of debt. For over 80 per cent of customers, the total debt amount (outstanding principal and arrears) exceeds the advanced loan amount. Since the onset of the crisis, the amount of principal debt has increased substantially compared to the real estate collateral pledged, currently amounting to 110 per cent on average or 140 per cent if we calculate the indicator based on total debt. The severity of the issue is further exacerbated by the fact that 70 per cent of nonperforming debtors live in smaller cities and localities, primarily in regions where the marketability of properties is limited. As a result, the prospects of a new start after selling the collateral may be limited for debtors. In examining nonperforming loan transactions, it is also essential to analyse income positions in depth, mainly in light of the potential rectification of the loan transactions through sustainable restructuring ...

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In the clinical practice, the evaluation of binocular vision is carried out with the traditional Worth-4-dot test, which is based on his classic theory, suggesting three hierarchical stages of stereovision (Worth, 1906). However, according to research nowadays, binocular vision rather involves parallel pathways. We do not know how the hierarchical organizational principles set forward in the Worth model can be related to the parallel processing pathway theory. We aimed to use reaction time (RT) measurement, a traditional psychophysical method, in a series of experiments, to examine the processing time of mechanisms in stereovision by using different types of cyclopean stimuli that are only visible binocularly by individuals who have intact stereopsis. We tested the effect of correlation, disparity and contrast on RT. Overall, the results suggest that the processing of cyclopean stimuli is more time consuming than non-cyclopean ones and that the speed further depends on the disparity and contrast of the stimuli. We have failed to prove that the processing of the different types of cyclopean stimuli takes a hierarchical order, rather, the results support the idea of parallel systems.

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Let be an infinite, strictly increasing sequence of non-negative integers. It is known (Horváth [2007]) that cannot hold from a point on. We will prove this result by using roots of unity, without integral. --------------------------------------------------- Legyen nemnegatív egészeknek egy végtelen, szigorúan növekedő sorozata. Ismert (Horváth [2007]), hogy nem lehet valahonnantól kezdve . Ezt az eredményt egységgyökök használatával, integrál nélkül fogjuk bizonyítani.

Let be an infinite, strictly increasing sequence of non-negative integers. It is known (Horváth [2007]) that cannot hold from a point on. We will prove this result by using roots of unity, without integral. --------------------------------------------------- Legyen nemnegatív egészeknek egy végtelen, szigorúan növekedő sorozata. Ismert (Horváth [2007]), hogy nem lehet valahonnantól kezdve . Ezt az eredményt egységgyökök használatával, integrál nélkül fogjuk bizonyítani.

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It is observed in this paper that the complexities of the equivalence and the equation solvability problems are not determined by the clone of the algebra. In particular, we prove that for the alternating group on four elements these problems have complexity in P; if we extend the group by the commutator as an extra operation, then the equivalence problem is coNP-complete and the equation solvability problem is NP-complete.

Many real world networks (graphs) are observed to be 'small worlds', i.e., the average path length among nodes is small. On the other hand, it is somewhat unclear what other average path length values networks can produce. In particular, it is not known what the maximum and the minimum average path length values are. In this paper we provide a lower estimation for the shortest average path length (l) values in connected networks, and the largest possible average path length values in networks with given size and density. To the latter end, we construct a special family of graphs and calculate their average path lengths. We also demonstrate the correctness of our estimation by simulations.

International audience; The main bioactive compounds of Trigonella foenum graecum L. (fenugreek) seeds are protodioscin, trigoneoside, diosgenin, yamogenin, which have anti-carcinogenic potency through inhibition of cell proliferation and inhibition of prostaglandin synthesis. We examined the effect of fenugreek on ALOX and COX genes in AKR/J H-2k mice exposed to dimethylbenz[a]anthracene (DMBA), the potent carcinogen. Expression pattern of these genes was determined by detecting the mRNA expression in various tissues (the lungs, liver, spleen and the kidneys) in four groups of mice. Two groups were fed with normal and two of them with fenugreek containing nutriment. Each group divided into DMBA treated and control groups. Mice were autopsied on the 7th day after DMBA treatment for mRNA isolation. Fenugreek consumption itself did not change gene expression compared to the control group. DMBA could increase expression of ALOX12, ALOX15, ALOX5 genes mainly in all organs. Fenugreek consumption was generally protective in each organ in different manner. DMBA treatment increased COX2 gene expression, but fenugreek were protective in all tissues examined. In COX1 gene, fenugreek diet could suppress the expression, except for spleen, independently from carcinogen exposure. Therefore via inhibiting the arachidonic acid metabolism fenugreek may prevent tumorigenesis

Food irradiation is a treatment of food by controlled amounts of ionizing radiation for a specific time to achieve certain desirable objectives. The process cannot increase the normal radioactivity level of the food, regardless of how long the food is exposed to the radiation, or how high energy dose is used. It can prevent the reproduction of food spoiling microorganisms, such as bacteria and moulds, by changing their molecular structure. It can also slow down the maturation of fruits and vegetables by altering the physiological processes of plant tissues. Alongside traditional methods of processing and preserving food, the technology of food irradiation is gaining more attention worldwide. Today, health and safety authorities in over 40 countries, have approved irradiation of over 60 different foods, ranging from spices to boned chicken meat. As of August 1999, over 30 countries and in more 60 irradiation facilities are irradiating food for commercial purposes. Interest is increasing in the process of irradiation because of high food losses from infestation, contamination, and spoilage; mounting concerns over food-borne diseases. The international food trade must meet strict standards. The FAO has estimated that 25% of all food production is lost worldwide after harvesting due to insects, bacteria and rodents. The use of irradiation alone will not solve all the problems of post-harvest food losses, but it can play an important role in reduction of losses and reducing the amount of chemicals used. Several countries, including USA, China, Japan, Hungary and other EU members use irradiation in case of one or more food products to control after harvest food losses. Foodborne diseases means a widespread threat to human health and they are an important cause of reduced economic productivity even in advanced countries. In the United States it was estimated in 1994 by a task force of the Council for Agricultural Science and Technology (CAST) that the number of cases may range from 6.5 million to 33 million annually and that deaths may be as high as 9,000 annually. The United States Department of Agriculture’s (USDA) Economic Research Service estimates that diseases caused by E. coli O157:H7 due to consumption of raw ground beef result in US $200 million to $440 million annual medical costs and productivity losses. In developing countries, diseases caused by parasites such as Taenia solium and Trichinella spiralis mean a major problem, and together with bacterial foodborne diseases, account for millions of cases per year. The relatively low doses of radiation needed to destroy certain bacteria in food can be useful in controlling foodborne disease. Frozen seafoods and frog legs, dry food ingredients, are irradiated for this purpose in Western Europe. Electron beam irradiation of poultry meat is carried out industrially in France. Spices are being irradiated, instead of being fumigated in many countries. The volume of irradiated spices and dried vegetable seasonings globally has increased significantly in recent years to over 60,000 tonnes. Trade of food products is a major factor in regional and international commerce, and the markets are growing. The inability of countries to satisfy each other’s quarantine and public health regulations is a major barrier of the food trade. For example, not all countries allow importation of chemically treated fruit. Moreover, major importing countries, including the USA and Japan, have banned the use of and the import of products treated with certain fumigants identified as health hazards. In 1996, the USDA issued a new rule to allow importation of fresh fruits and vegetables treated by radiation against fruit flies. The problem is most acute for developing countries whose economies are still largely based on food and agricultural production and the revenues from export. Radiation processing offers these countries an alternative to fumigation and some other treatments.

Chomp is a 50 year-old game played on a partially ordered set P. It has been in the center of interest of several mathematicians since then. Even when P is simply a 3 × n lattice, we have almost no information about the winning strategy. In this paper we present a new approach and a cubic algorithm for computing the winning positions for this case. We also prove that from the initial positions there are infinitely many winning moves in the third row.

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We have isolated a 483-bp-long full-length cDNA clone encoding a non-symbiotic hemoglobin called Mhb1, the first one found in alfalfa. This non-symbiotic hemoglobin is a single copy gene localized in linkage group 4 in diploid Medicago genome. The Mhb1 mRNA was found only in the roots of alfalfa plants. The Mhb1 gene was inducible by hypoxia and showed no induction by cold stress treatment. The Mhb1 transcript level increased at the G2/M boundary in a synchronized alfalfa cell suspension culture. The majority of Mhb1 protein was shown to be localized in the nucleus and smaller amounts were detected in the cytoplasm. A potential link to the nitric oxide signalling pathway is also discussed.

The measurement and simulation results for described VCO topology showed strong correlation between local frequency selective increase of the negative input resistance and the phase noise increasing in the same frequency band. For rigorous oscillator analysis it must be taken in consideration the impact of the varactor nonlinearities with nonlinear transistor input impedance. Active elements should be classified regarding the 1/f noise, because the 1/f noise could be converted to the oscillator phase noise.