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SUMMARY Mature inflorescences of sunflowers (Helianthus annuus) orient constantly on average to the geographical east. According to one of the explanations of this phenomenon, the eastward orientation of sunflower inflorescences increases the number of attracted insect pollinators. We tested this hypothesis in three field experiments performed in flowering sunflower plantations. In experiments 1 and 2 we measured the number of insects trapped by the vertical walls of sticky sunflower models facing north, east, south, and west. In experiment 3 we counted the pollinators' landings on real sunflower inflorescences facing naturally east or turned artificially toward north, south, and west. We found that the all‐day number of pollinators (predominantly bees) attracted to model and real sunflowers in H. annuus plantations is independent of the azimuth direction of sunflower heads, and after 10 h in the morning, the average number of pollinators counted every 20 min is practically constant in the rest of the day. [ABSTRACT FROM AUTHOR]

The electric vehicle (EV) industry challenges battery joining technologies by requiring higher energy density both by mass and volume. Improving the energy density via new battery chemistry would be the holy grail but is seriously hindered and progresses slowly. In the meantime, alternative ways, such as implementing more efficient cell packaging by minimising the electrical resistance of joints, are of primary focus. In this paper, we discuss the challenges associated with the electrical characterisation of laser-soldered joints in general, and the minimisation of their resistive losses, in particular. In order to assess the impact of joint resistance on the overall resistance of the sample, the alteration in resistance was monitored as a function of voltage probe distance and modelled by finite element simulation. The experimental measurements showed two different regimes: one far from the joint area and another in its vicinity and within the joint cross-section. The presented results confirm the importance of the thickness of the filler material, the effective and total soldered area, and the area and position of the voids within the total soldered area in determining the electrical resistance of joints. [ABSTRACT FROM AUTHOR]

With the proliferation of electric drivetrains, the development and optimization of joining techniques for the fabrication of battery packs became a prime manufacturing topic. Decreasing the electrical resistance and increasing the mechanical strength of the welds at the individual cell level are of great importance not only for productivity and efficiency but also for safety and sustainability purposes. Lasers offer an advanced, highly automatable solution for battery cell joining. Usually, the optimization focuses on the laser parameters or the scanning speed. However, the most widespread battery welding geometry, the so-called lap geometry, allows alternative possibilities for joint property optimization. The novelty of our approach is that we focus on systematic experimental investigation of the effects of dimensional parameters and the layout of the weld pattern. Systematic experiments reveal that the shape and size of the weld area have substantial effect on the properties of the laser welded joint. Our results prove that a rather substantial gain can be achieved in both the electrical and mechanical properties when the weld consists of at least two parallel bead segments. We also show that it is beneficial by both means if the segments have the greatest individual length and placed apart at the maximum feasible distance. The orientation of the straight segments affects the mechanical and electrical behavior differently: strongest welds consist of weld segments oriented in parallel, while the smallest resistance can be achieved using segments oriented perpendicular to the direction of current flow, respectively. [ABSTRACT FROM AUTHOR]

Several machine learning-based methods are available in the literature to find anomalies in large log sequences. Recently, deep learning based solutions demonstrated promising performance in this domain. The majority of these methods formulate the problem as a classification task, where the final layer of the neural network model is a softmax layer. This paper presents a different, regression-based approach. The input of the model is a sequence of numeric vectors representing the semantic information of the log lines, and the output is also a numeric vector corresponding to the expected log line. To cope with the inherent uncertainty of log sequences, we introduce "Top-K" layers, allowing the model to emit multiple predictions, from which the best one is chosen. This feature, together with the "Top-K" loss function, makes it possible to develop an unsupervised, fully template-less model that can also handle log lines it has never seen during the training phase, which is essential for online applications. On benchmark data sets we demonstrate that the model achieves competitive performance. [ABSTRACT FROM AUTHOR]

The study introduces the current situation of electric vehicle technologies, the possibilities and possible directions of their market, as well as the economic and environmental aspects in the eastern region of the EU, with special regard to Hungary. Our calculations show that despite the higher costs of ownership, in the case of 7 years of use (among Hungarian conditions), the total cost of the Battery Electric Vehicles (BEV) is lower than that of the Internal Combustion Engine Vehicles (ICEV) in each of the four segments analysed. The purchasing power of the population in the eastern regions of the EU is clearly lower compared to the western regions, yet people in this region spend beyond their financial means on motorization. Despite its unfavourable position, Hungary is in a particularly advantageous position compared to other countries in the region per vehicle and per capita in terms of the spread of BEVs. In the long run, even taking higher prices into account, the use of electric cars, in general, has significant advantages from an economic point of view; lower maintenance costs and fuel prices (especially with increased use) make EVs more cost-effective overall. [ABSTRACT FROM AUTHOR]

The differences between the consecutive world-records of shot put and hammer throw tendentiously decrease. Therefore, nowadays it would be worth taking into account the influence of certain environmental factors on the range L, such as the latitude and release azimuth direction. Both factors exert influence on L by the centrifugal acceleration acentrigugal and Coriolis acceleration aCoriolis induced by the Earth's rotation. The aim of this work is to reveal how the world-record ranking numbers would change, if acentrigugal and aCoriolis as well as the athletes' height h were taken into account during the validation of the outdoor world records of senior female and male shot-putters and hammer-throwers. Using computer modelling, we reconstruct here the release velocities v of shots and hammers and the normalized muscle work of shot-putters achieved at the 20 best consecutive world records. We determined numerous changes of world-record ranking numbers of shot put and hammer throw due to the influence of acentrigugal, aCoriolis and h. Height h has the largest effect on the range L, acentrigugal has a medium influence, and aCoriolis possesses the least impact on L. The physically most correct way would be to consider the release velocity v of the shot/hammer (easily measurable with an ultrasound/laser Doppler gauge) as the real performance of athletes, because it is practically independent of the environmental factors, and thus is a much better ranking measure of world records than the range. [ABSTRACT FROM AUTHOR]

We propose a method called Bilateral‐Weighted Online Adaptive Isolation Forest (BWOAIF) for unsupervised anomaly detection based on Isolation Forest (IF), which is applicable to streaming data and able to cope with concept drift. Similar to IF, the proposed method has only few hyperparameters whose effect on the performance are easy to interpret by human intuition and therefore easy to tune. BWOAIF ingests data and classifies it as normal or anomalous, and simultaneously adapts its classifier by removing old trees as well as by creating new ones. We show that BWOAIF adapts gradually to slow concept drifts, and, at the same time, it is able to adapt fast to sudden changes of the data distribution. Numerical results show the efficacy of the proposed algorithm and its ability to learn different classes of concept drifts, such as slow/fast concept shift, concept split, concept appearance, and concept disappearance. [ABSTRACT FROM AUTHOR]

Piecewise homogeneous Markov fluid models are composed by homogeneous intervals where the model is governed by an interval dependent pair of generators and the model behaviour changes at the boundaries. The main difficulty of the transient analysis of piecewise homogeneous Markov fluid models is the appropriate description of the various boundary cases. The paper proposes an analytical approach to handle the wide variety of the possible boundary cases in a relatively simple to describe and implement manner. [ABSTRACT FROM AUTHOR]

Amber contains numerous well-preserved adult aquatic insects (e.g., aquatic beetles – Coleoptera, water bugs – Heteroptera, dragonflies – Odonata, caddisflies – Trichoptera, mayflies – Ephemeroptera, stone flies – Plecoptera). Since amber is fossilised resin of terrestrial conifer trees, it is an enigma how aquatic insects have ended up in the resin. Based on field studies in a Hungarian forest along a freshwater creek we suggest that tree resin traps water-seeking flying polarotactic aquatic insects because of its property to polarise reflected light. The sticky tree resin was modelled by a water-proof, transparent, colourless insect-monitoring glue laid on vertical and horizontal fallen tree trunks next to the creek. Adults of various polarotactic aquatic insect species were trapped only by the horizontal sticky trunk. In earlier field experiments we showed that these insects find water by means of the horizontal polarisation of water-reflected light, and therefore are attracted to and land on all surfaces which reflect horizontally polarised light. Using imaging polarimetry, we revealed the criterion of polarisation-based trapping by resiny tree trunks. According to our observations, flying aquatic insects can be trapped by sticky (resiny) regions of fallen tree trunks that reflect horizontally polarised light and thus attract polarotactic species. The resin continues to flow out of the trees even when fallen over or fractured in a storm. Our findings support and complement an earlier hypothesis, according to which amber-preserved adult aquatic insects have been trapped by resiny bark when they dispersed over land. [ABSTRACT FROM AUTHOR]

The article presents a numerical analysis approach for the transient solution of a piecewise homogeneous quasi-birth-death process. The proposed approach computes the transient probabilities based on the linear combination of matrix geometric series in Laplace transform domain, and builds on the availability of an efficient numerical inverse Laplace transformation method. [ABSTRACT FROM AUTHOR]

The mature inflorescence of sunflowers (Helianthus annuus) orients eastward after its anthesis (the flowering period, especially the maturing of the stamens), from which point it no longer tracks the Sun. Although several hypothetical explanations have been proposed for the ecological functions of this east facing, none have been tested. Here we propose an atmospheric-optical explanation. Using (i) astronomical data of the celestial motion of the Sun, (ii) meteorological data of diurnal cloudiness for Boone County located in the region from which domesticated sunflowers originate, (iii) time-dependent elevation angle of mature sunflower heads, and (iv) absorption spectra of the inflorescence and the back of heads, we computed the light energy absorbed separately by the inflorescence and the back between anthesis and senescence. We found that the inflorescences facing east absorb the maximum radiation, being advantageous for seed production and maturation, furthermore west facing would be more advantageous than south facing. The reason for these is that afternoons are cloudier than mornings in the cultivation areas of sunflowers. Since the photosynthesizing green back of mature heads absorbs maximal energy when the inflorescence faces west, maximizing the energy absorbed by the back cannot explain the east facing of inflorescences. The same results were obtained for central Italy and Hungary, where mornings are also less cloudy than afternoons. In contrast, in south Sweden, where mornings are cloudier than afternoons, west-facing mature inflorescences would absorb the maximum light energy. We suggest that the domesticated Helianthus annuus developed an easterly final orientation of its mature inflorescence, because it evolved in a region with cloudier afternoons. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

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 in Hungary 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 T so that above 58 °C tabanids spent no longer than 1 s on the surface. The horizontally polarised light reflected from solar 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. [ABSTRACT FROM AUTHOR]

This paper considers a multi-type fluid queue with priority service. The input fluid rates are modulated by a Markov chain, which is common for all fluid types. The service rate of the queue is constant. Various performance measures are derived, including the Laplace–Stieltjes transform and the moments of the stationary waiting time of the fluid drops and the queue length distributions. An Erlangization-based numerical method is also provided to approximate the waiting time and the queue length distributions up to arbitrary precision. All performance measures are formulated as reward accumulation problems during busy periods of simple Markovian fluid flow models, for which efficient matrix-analytic solutions are provided, enabling us to solve large models with several hundred states. [ABSTRACT FROM AUTHOR]

Blood-sucking horseflies (tabanids) prefer warmer (sunlit, darker) host animals and generally attack them in sunshine, the reason for which was unknown until now. Recently, it was hypothesized that blood-seeking female tabanids prefer elevated temperatures, because their wing muscles are quicker and their nervous system functions better at a warmer body temperature brought about by warmer microclimate, and thus they can more successfully avoid the host's parasite-repelling reactions by prompt takeoffs. To test this hypothesis, we studied in field experiments the success rate of escape reactions of tabanids that landed on black targets as a function of the target temperature, and measured the surface temperature of differently coloured horses with thermography. We found that the escape success of tabanids decreased with decreasing target temperature, that is escape success is driven by temperature. Our results explain the behaviour of biting horseflies that they prefer warmer hosts against colder ones. Since in sunshine the darker the host the warmer its body surface, our results also explain why horseflies prefer sunlit dark (brown, black) hosts against bright (beige, white) ones, and why these parasites attack their hosts usually in sunshine, rather than under shaded conditions. [ABSTRACT FROM AUTHOR]

We provide a polynomial time algorithm for deciding the equation solvability problem over finite groups that are semidirect products of a p -group and an Abelian group. As a consequence, we obtain a polynomial time algorithm for deciding the equivalence problem over semidirect products of a finite nilpotent group and a finite Abelian group. The key ingredient of the proof is to represent group expressions using a special polycyclic presentation of these finite solvable groups. [ABSTRACT FROM AUTHOR]

The anomaly detection method presented by this article has a special feature: it not only indicates whether or not an observation is anomalous but also tells what exactly makes an anomalous observation unusual. Hence, it provides support to localize the reason of the anomaly. The proposed approach is model based; it relies on the multivariate probability distribution associated with the observations. Since the rare events are present in the tails of the probability distributions, we use copula functions, which are able to model the fat-tailed distributions well. The presented procedure scales well; it can cope with a large number of high-dimensional samples. Furthermore, our procedure can cope with missing values as well, which occur frequently in high-dimensional datasets. In the second part of the article, we demonstrate the usability of the method through a case study, where we analyze a large dataset consisting of the performance counters of a real mobile telecommunication network. Since such networks are complex systems, the signs of sub-optimal operation can remain hidden for a potentially long time. With the proposed procedure, many such hidden issues can be isolated and indicated to the network operator. [ABSTRACT FROM AUTHOR]

This paper presents matrix-exponential (ME) distributions, whose squared coefficient of variation (SCV) is very low. Currently, there is no symbolic construction available to obtain the most concentrated ME distributions, and the numerical optimization-based approaches to construct them have many pitfalls. We present a numerical optimization-based procedure which avoids numerical issues. [ABSTRACT FROM AUTHOR]

At the time of the final publication of the paper, in December 2016, Yixin Zhao's affiliation had changed. [ABSTRACT FROM AUTHOR]

Intelligent transportation systems are becoming more and more important nowadays. In these systems, vehicles and possibly the infrastructure communicate with each other by vehicular ad hoc networks (VANETs). VANETs are being deployed and widely used in urban as well as in highway applications. Several standard use cases have been identified over the last decade (i.e., alert messages, car following support, data exchange between vehicles). In this paper, we focus on the alert message propagation on the highway. We derive the stationary and the transient solution of the message propagation distance by constant vehicle speed. Since these messages frequently indicate an accident on the road leading to a traffic jam, we extend the model to take the queueing system due to the traffic jam also into consideration. Our analytical results are compared with SUMO-/Veins-based simulations. [ABSTRACT FROM AUTHOR]

Evolutionary traps are scenarios in which animals are fooled by rapidly changing conditions into preferring poor‐quality resources over those that better improve survival and reproductive success. The maladaptive attraction of aquatic insects to artificial sources of horizontally polarized light (e.g., glass buildings, asphalt roads) has become a first model system by which scientists can investigate the behavioral mechanisms that cause traps to occur. We employ this field‐based system to experimentally investigate (a) in which portion(s) of the spectrum are polarizationally water‐imitating reflectors attractive to nocturnal terrestrial and aquatics insects, and (b) which modern lamp types result in greater attraction in this typical kind of nocturnal polarized light pollution. We found that most aquatic taxa exhibited preferences for lamps based upon their color spectra, most having lowest preference for lamps emitting blue and red light. Yet, despite previously established preference for higher degrees of polarization of reflected light, most aquatic insect families were attracted to traps based upon their unpolarized spectrum. Chironomid midges, alone, showed a preference for the color of lamplight in both the horizontally polarized and unpolarized spectra indicating only this family has evolved to use light in this color range as a source of information to guide its nocturnal habitat selection. These results demonstrate that the color of artificial lighting can exacerbate or reduce its attractiveness to aquatic insects, but that the strength of attractiveness of nocturnal evolutionary traps, and so their demographic consequences, is primarily driven by unpolarized light pollution. This focuses management attention on limiting broad‐spectrum light pollution, as well as its intentional deployment to attract insects back to natural habitats. [ABSTRACT FROM AUTHOR]

The aim of this paper is to give a refinement of Walker's inequality. To this, we will use a "self-improvement" of the Cauchy–Schwarz inequality for random variables. [ABSTRACT FROM AUTHOR]

Binocular depth perception is an important mechanism to segregate the visual scene for mapping relevant objects in our environment. Convergent evidence from psychophysical and neurophysiological studies have revealed asymmetries between the processing of near (crossed) and far (uncrossed) binocular disparities. The aim of the present study was to test if near or far objects are processed faster and with higher contrast sensitivity in the visual system. We therefore measured the relationship between binocular disparity and simple reaction time (RT) as well as contrast gain based on the contrast-RT function in young healthy adults. RTs were measured to suddenly appearing cyclopean target stimuli, which were checkerboard patterns encoded by depth in dynamic random dot stereograms (DRDS). The DRDS technique allowed us to selectively study the stereoscopic processing system by eliminating all monocular cues. The results showed that disparity and contrast had significant effects on RTs. RTs as a function of disparity followed a U-shaped tuning curve indicating an optimum at around 15 arc min, where RTs were minimal. Surprisingly, the disparity tuning of RT was much less pronounced for far disparities. At the optimal disparity, we measured advantages of about 80 ms and 30 ms for near disparities at low (10%) and high (90%) contrasts, respectively. High contrast always reduced RTs as well as the disparity dependent differences. Furthermore, RT-based contrast gains were higher for near disparities in the range of disparities where RTs were the shortest. These results show that the sensitivity of the human visual system is biased for near versus far disparities and near stimuli can result in faster motor responses, probably because they bear higher biological relevance. [ABSTRACT FROM AUTHOR]

Let PPol ( R ) denote the group of permutation polynomial functions over the finite, commutative, unital ring R under composition. We generalize numerous results about permutation polynomials over Z p n to local rings by treating them under a unified manner. In particular, we provide a natural wreath product decomposition of permutation polynomial functions over the maximal ideal M and over the finite field R / M . We characterize the group of permutation polynomial functions over M whenever the condition M | R / M | = { 0 } applies. Then we derive the size of PPol ( R ) , thereby generalizing the same size formulas for Z p n . Finally, we completely characterize when the group PPol ( R ) is solvable, nilpotent, or abelian. [ABSTRACT FROM AUTHOR]

We prove a necessary and sufficient condition for a function being a polynomial function over a finite, commutative, unital ring. Further, we give an algorithm running in quasilinear time that determines whether or not a function given by its function table can be represented by a polynomial, and if the answer is yes then it provides one such polynomial. [ABSTRACT FROM AUTHOR]

This paper presents a matrix-analytic solution for second-order Markov fluid models (also known as Markov-modulated Brownian motion) with level-dependent behavior. A set of thresholds is given that divide the fluid buffer into homogeneous regimes. The generator matrix of the background Markov chain, the fluid rates (drifts) and the variances can be regime dependent. The model allows the mixing of second-order states (with positive variance) and first-order states (with zero variance) and states with zero drift. The behavior at the upper and lower boundary can be reflecting, absorbing, or a combination of them. In every regime, the solution is expressed as a matrix-exponential combination, whose matrix parameters are given by the minimal nonnegative solution of matrix quadratic equations that can be obtained by any of the well-known solution methods available for quasi birth death processes. The probability masses and the initial vectors of the matrix-exponential terms are the solutions of a set of linear equations. However, to have the necessary number of equations, new relations are required for the level boundary behavior, relations that were not needed in first-order level dependent and in homogeneous (non-level-dependent) second-order fluid models. The method presented can solve systems with hundreds of states and hundreds of thresholds without numerical issues. [ABSTRACT FROM AUTHOR]

The flow semigroup, introduced by Rhodes, is an invariant for digraphs and a complete invariant for graphs. After collecting previous partial results together, we refine and prove Rhodes's conjecture on the structure of the maximal groups in the flow semigroup for finite, antisymmetric, strongly connected digraphs. Building on this result, we investigate and fully describe the structure and actions of the maximal subgroups of the flow semigroup acting on all but points for all finite digraphs and graphs for all . A linear algorithm (in the number of edges) is presented to determine these so-called 'defect groups' for any finite (di)graph. Finally, we prove that the complexity of the flow semigroup of a 2-vertex connected (and strongly connected di)graph with vertices is , completely confirming Rhodes's conjecture for such (di)graphs. [ABSTRACT FROM AUTHOR]

Pro accumulation in plants is a well-documented physiological response to osmotic stress caused by drought or salinity. In Arabidopsis (Arabidopsis thaliana), the stress and ABA-induced Δ1-PYRROLINE-5-CARBOXYLATE SYNTHETASE1 (P5CS1) gene was previously shown to control Pro biosynthesis in such adverse conditions. To identify regulatory factors that control the transcription of P5CS1, Y1H screens were performed with a genomic fragment of P5CS1, containing 1.2-kB promoter and 0.8-kb transcribed regions. The myeloblastosis (MYB)-type transcription factors PHOSPHATE STARVATION RESPONSE1 (PHR1) and PHR1-LIKE1 (PHL1) were identified to bind to P5CS1 regulatory sequences in the first intron, which carries a conserved PHR1-binding site (P1BS) motif. Binding of PHR1 and PHL1 factors to P1BS was confirmed by Y1H, electrophoretic mobility assay and chromatin immunoprecipitation. Phosphate starvation led to gradual increase in Pro content in wild-type Arabidopsis plants as well as transcriptional activation of P5CS1 and PRO DEHYDROGENASE2 genes. Induction of P5CS1 transcription and Pro accumulation during phosphate deficiency was considerably reduced by phr1 and phl1 mutations and was impaired in the ABA-deficient aba2-3 and ABA-insensitive abi4-1 mutants. Growth and viability of phr1phl1 double mutant was significantly reduced in phosphate-depleted medium, while growth was only marginally affected in the aba2-3 mutants, suggesting that ABA is implicated in growth retardation in such nutritional stress. Our results reveal a previously unknown link between Pro metabolism and phosphate nutrition and show that Pro biosynthesis is target of cross talk between ABA signaling and regulation of phosphate homeostasis through PHR1- and PHL1-mediated transcriptional activation of the P5CS1 gene. [ABSTRACT FROM AUTHOR]

Phase-type (PH) distributions are being used to model a wide range of phenomena in performance and dependability evaluation. The resulting models may be employed in analytical as well as in simulation-driven approaches. Simulations require the efficient generation of random variates from PH distributions. PH distributions have different representations and different associated computational costs for pseudo random-variate generation (PRVG). In this paper we study the problem of efficient representation and efficient generation of PH distributed variates. We introduce various PH representations of different sizes and optimize them according to different cost functions associated with PRVG. [ABSTRACT FROM AUTHOR]

In a quasi-birth-death (QBD) queue, the level forward and level backward transitions of a QBD-type Markov chain are interpreted as customer arrivals and services. In the generalized QBD queue considered in this paper, arrivals and services can occur in matrix-geometrically distributed batches. This paper presents the queue length and sojourn time analysis of generalized QBD queues. It is shown that, if the number of phases is N, the number of customers in the system is order- N matrix-geometrically distributed, and the sojourn time is order- $$N^2$$ matrix-exponentially distributed, just like in the case of classical QBD queues without batches. Furthermore, phase-type representations are provided for both distributions. In the special case of the arrival and service processes being independent, further simplifications make it possible to obtain a more compact, order- N representation for the sojourn time distribution. [ABSTRACT FROM AUTHOR]

We study the length of polynomials over finite simple non-Abelian groups needed to realize Boolean functions. We apply the results for bounding the length of 5-permutation branching programs recognizing a Boolean set. Moreover, for Boolean and general functions on these groups, we present upper bounds on the length of shortest polynomials computing an arbitrary n -ary Boolean or general function, or a function given by another polynomial. [ABSTRACT FROM AUTHOR]

The mechanism that forms the different resonant families of the asteroid belt between the orbits of Jupiter and Mars is not completely understood. To study the resonant capture mechanism and the origin of orbits of some asteroid families in mean motion resonances with Jupiter, furthermore to give a possible explanation of this problem, we performed in situ numerical simulations of the 3-dimensional semi-analytical model of the Sun-Jupiter-particle system. We examined the numbers and orbits of particles captured along the Jupiter's present orbit (including the L3, L4 and L5 Lagrange points) for 7000 Jupiter years. In our simulations we did not distinguish between planetesimals, interplanetary dust and asteroids, because we investigated the restricted three-body problem taking into account only gravitation. We found that the asteroid families in 4:3, 1:1, 4:5, 3:4, 2:3, 5:8, 4:7 and 5:9 resonances may have formed from the asteroids captured, launched and kept on their orbits not only by the L4 and L5 points, but also by the unstable L3 point and certain areas along the Jupiter's path. Furthermore, we found possible new asteroid families in 4:5 and 3:4 resonances, no any member of which have yet been identified. Thus, Jupiter forms a shield which protects the inner Solar System from asteroids moving with speeds not significantly differing from that of Jupiter. • Our aim is to demonstrate the resonant capture mechanism of dynamically cold particles along the Jupiter's orbit. • We performed in situ simulations of the 3D semi-analytical model of the Sun-Jupiter-particle system. • The capture efficiency of both the L4 and L5 points at the Jupiter's aphelion is 24% higher than at its perihelion. • The particles captured along the Jupiter's present orbit form the 1:1, 4:3, 4:5, 3:4, 2:3, 5:8, 4:7, 5:9 resonance families. [ABSTRACT FROM AUTHOR]

We provide polynomial time algorithms for deciding equation solvability and identity checking over groups that are semidirect products of two finite Abelian groups. Our main method is to reduce these problems to the sigma equation solvability and sigma equivalence problems over modules for commutative unital rings. [ABSTRACT FROM AUTHOR]

Abstract: In 2004 a counterexample was given for a 1965 result of R.J. Elliott claiming that discrete spectral synthesis holds on every Abelian group. Here we present a ring-theoretical approach to this problem, and show that some varieties fail to have spectral synthesis. In particular, we give a new proof for the result of the second author that spectral synthesis does not hold on Abelian groups with infinite torsion free rank. [Copyright &y& Elsevier]

We prove that ${ \mathbb{Z} }_{{p}^{n} } $ and ${ \mathbb{Z} }_{p} [t] / ({t}^{n} )$ are polynomially equivalent if and only if $n\leq 2$ or ${p}^{n} = 8$. For the proof, employing Bernoulli numbers, we explicitly provide the polynomials which compute the carry-on part for the addition and multiplication in base $p$. As a corollary, we characterize finite rings of ${p}^{2} $ elements up to polynomial equivalence. [ABSTRACT FROM AUTHOR]

Objectives. Inflammatory bowel diseases (IBD) have a huge impact on the patients' lives and require continuous medication and long-term medical follow-up. The Short Form Health Survey (SF-36) is a commonly used questionnaire measuring health-related quality of life (HRQOL). Our aim was to evaluate whether HRQOL influences medication adherence and vice versa in IBD patients, and to find relationships between demographic parameters, therapeutic modalities and non-adherence or HRQOL. Patients and methods. Five hundred ninety-two IBD patients treated at six Hungarian tertiary centers were enrolled. Patients completed the SF-36 questionnaire and a medication adherence report scale during their visits. The associations between demographic parameters, HRQOL, different kinds of therapies and non-adherence were analyzed. Results. The most affected dimension was physical functioning and least affected were the social functions. About 42.7% of the patients revealed their HRQOL to be acceptable. About 74.6% of the patients believed that the prescribed medications actually improved their HRQOL. Diarrhea was the most common and most severe symptom during the course of the disease. Non-adherence was reported in 13.4% of the patients. 'Forgetting to take the medication' was the main reason for non-adherence in 67.6% of the cases. Medication adherence was significantly higher among nonsmoker patients, and also in the case of immunomodulator therapy. There was no association between the sum of HRQOL and different subscores and non-adherence. Conclusion. Inflammatory bowel disease is associated with low HRQOL, which is not affected by drug therapy. The impaired quality of life in IBD is mainly influenced by the disease itself. [ABSTRACT FROM AUTHOR]

We present a new solution of the word problem of free algebras in varieties generated by iterated semidirect products of semilattices. As a consequence, we provide asymptotical bounds for free spectra of these varieties. In particular, each finite -trivial (and, dually, each finite -trivial) semigroup has a free spectrum whose logarithm is bounded above by a polynomial function. [ABSTRACT FROM AUTHOR]

Abstract: 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. [Copyright &y& Elsevier]

Abstract: Aquatic and water-associated insects need to locate suitable bodies of water to lay their eggs in and allow their aquatic larvae to develop. More than 300 species are known to solve this task by positive polarotaxis, relying primarily on the horizontally polarized light reflected from the water surface. The yellow fever mosquito Aedes (Stegomyia) aegypti has been thought to be an exception, locating its breeding habitats by chemical cues like odour of conspecifics, their eggs, or water vapour. We now demonstrate through dual-choice experiments that horizontally polarized light can also attract ovipositing Ae. aegypti females when the latter are deprived of chemical cues: water-filled transparent egg-trays illuminated by horizontally polarized light from below gained a 94.2% higher total number of eggs than trays exposed to unpolarized light, but only when no chemical substances capable of functioning as cues were present. Ae. aegypti is the first known water-associated insect in which polarotaxis exists, but does not play a dominant role in locating water bodies and can be constrained in the presence of chemical cues. [Copyright &y& Elsevier]

It is proved that the equation solvability problem can be solved in polynomial time for finite nilpotent rings. Ramsey's theorem is employed in the proof. Then, using the same technique, a theorem of Goldmann and Russell is reproved: the equation solvability problem can be solved in polynomial time for finite nilpotent groups. [ABSTRACT FROM AUTHOR]

We prove that the extended equivalence problem is solvable in polynomial time for finite nilpotent groups, and coNP-complete, otherwise. We prove that the extended equation solvability problem is solvable in polynomial time for finite nilpotent groups, and NP-complete, otherwise. [ABSTRACT FROM AUTHOR]

Abstract: Non-biting midges (Chironomidae, Diptera) are widely distributed aquatic insects. The short-living chironomid adults swarm in large numbers above water surfaces, and are sometimes considered a nuisance. They are vectors of certain bacteria, and have a key-role in benthic ecosystems. Optical cues, involving reflection-polarization from water, were found to be important in the habitat selection by three Mediterranean freshwater chironomid species. In this work we report on our multiple-choice experiments performed in the field with several other European freshwater chironomid species. We show that the investigated non-biting midges are positively polarotactic and like many other aquatic insects their females are attracted to horizontally polarized light. Our finding is important in the visual ecology of chironomids and useful in the design of traps for these insects. [Copyright &y& Elsevier]

The aim of our study was to determine the radiographic prevalence of hip and knee osteoarthritis and compare our results with prevalence data reported by other studies, as no similar study had been performed in Hungary previously. Our aim was also to investigate the usefulness of the different radiological scoring methods for the definition of osteoarthritis. Patients who earlier reported complaints and gave written consent were asked to participate in a clinical follow-up. In the 682 participants Harris hip score, visual analogue pain scale values for both joints, Knee Society score and knee functional score were calculated. Weight-bearing radiographs were taken of both joints. Kellgren-Lawrence radiological evaluation was performed and osteoarthritis prevalence was defined. Hip osteoarthritis was found in 109 cases (16.49%), and knee osteoarthritis was found in 111 cases (16.54%). Harris hip score, Knee Society score, functional score and visual analogue scale values were significantly worse in people with radiographically proven osteoarthritis compared to the control group ( p < 0.05). Significantly higher osteoarthritis prevalence of both joints was found in those with increased body mass index values. Age also plays a significant role in the development of both hip and knee osteoarthritis. No significant difference was observed between male and female participants regarding osteoarthritis prevalence. The Kellgren-Lawrence score with a cut-off value of 2 or more is a useful evaluation method for the detection of osteoarthritis prevalence in epidemiological studies; according to our observations, in clinical practice a cut-off value of three or more is more relevant. [ABSTRACT FROM AUTHOR]

cross-sectional epidemiological study via personal interviews was performed regarding low back pain and its related clinical aspects in a Hungarian sample of 10,000 people. Joining the international campaign of the 'Bone and Joint Decade', our aim was to give data on low back pain prevalence and to explore the underlying possible clinical conditions in a Central European adult and adolescent population. Ten thousand people aged 14-65, selected randomly by the Hungarian central office of statistics from three counties of the south-western Hungarian region, were surveyed using a special questionnaire focusing on low back pain and other degenerative spinal symptoms. People with low back pain complaints and written consent were asked to participate in a further clinical investigation, where radiological and clinical assessment was performed. A total of 4,389 persons (44.1%) reported low back pain in the last month at the time of the survey. Work absenteeism due to low back pain affected 2,140 persons (21.5%). A total of 292 people (2.9%) had already undergone spinal surgery. Upon request 682 people came for a clinical follow-up, where thorough physical examination and radiological analysis was performed and results were statistically interpreted. The Oswestry disability index (ODI) in the examined group of patients averaged 35.1%; radiological degenerative signs were observed in 392/682 (57.5%). Individuals with signs of radiological degeneration had a statistically significant higher ODI value, age, and a higher, yet not significantly increased BMI value than radiographically negative patients ( p < 0.05). Co-existence of hip and knee osteoarthritis was also investigated. Higher osteoarthritis prevalence was found in individuals with radiographic signs of spinal degeneration. Details of the survey and clinical investigations are discussed. [ABSTRACT FROM AUTHOR]

Human-made objects (e.g., buildings with glass surfaces) can reflect horizontally polarized light so strongly that they appear to aquatic insects to be bodies of water. Insects that lay eggs in water are especially attracted to such structures because these insects use horizontal polarization of light off bodies of water to find egg-laying sites. Thus, these sources of polarized light can become ecological traps associated with reproductive failure and mortality in organisms that are attracted to them and by extension with rapid population declines or collapse. Solar panels are a new source of polarized light pollution. Using imaging polarimetry, we measured the reflection-polarization characteristics of different solar panels and in multiple-choice experiments in the field we tested their attractiveness to mayflies, caddis flies, dolichopodids, and tabanids. At the Brewster angle, solar panels polarized reflected light almost completely (degree of polarization d ≈ 100%) and substantially exceeded typical polarization values for water (d ≈ 30-70%). Mayflies (Ephemeroptera), stoneflies (Trichoptera), dolichopodid dipterans, and tabanid flies (Tabanidae) were the most attracted to solar panels and exhibited oviposition behavior above solar panels more often than above surfaces with lower degrees of polarization (including water), but in general they avoided solar cells with nonpolarizing white borders and white grates. The highly and horizontally polarizing surfaces that had nonpolarizing, white cell borders were 10- to 26-fold less attractive to insects than the same panels without white partitions. Although solar panels can act as ecological traps, fragmenting their solar-active area does lessen their attractiveness to polarotactic insects. The design of solar panels and collectors and their placement relative to aquatic habitats will likely affect populations of aquatic insects that use polarized light as a behavioral cue. [ABSTRACT FROM AUTHOR]

Steelmaking with a Linz-Donawitz converter is a complex industrial process, where, due to the lack of exact mathematical (physical-chemical) models, the construction of a blackbox model based on noisy and imprecise data is required. To construct a good model, a large number of such input-output samples should be used, which calls for a method that is sparse, in the sense that the resulting model complexity is independent of the sample number, and robust to reduce the effects of noise. Lately, support vector machines (SVMs) have successfully been applied to a number of such problems. The main problem with traditional SYM is its high algorithmic complexity, which makes it infeasible for really large databases. The least-squares SVM (LS-SVM) solves this problem, but the resulting model is not sparse. Our solution uses a sparse and robust extension of LS-SVM that leads to good results compared to other methods (such as MLPs) applied to the same problem. [ABSTRACT FROM AUTHOR]

Abstract: In a paper published in J. ACM in 1990, Tobias Nipkow asserted that the problem of deciding whether or not an equation over a nontrivial functionally complete algebra has a solution is NP-complete. However, close examination of the reduction used shows that only a weaker theorem follows from his proof, namely that deciding whether or not a system of equations has a solution is NP-complete over such an algebra. Nevertheless, the statement of Nipkow is true as shown here. As a corollary of the proof we obtain that it is coNP-complete to decide whether or not an equation is an identity over a nontrivial functionally complete algebra. [Copyright &y& Elsevier]

Abstract: Aquatic insects and insects associated with water use horizontally polarized light (i.e., positive polarotaxis) to detect potential aquatic or moist oviposition sites. Mosquitoes lay their eggs onto wet substrata, in water, water-filled tree/rock holes, or man-made small containers/bottles/old tyres containing water. Until now it has remained unknown whether mosquitoes are polarotactic or not. The knowledge how mosquitoes locate water would be important to develop new control measures against them. Thus, we studied in dual-choice laboratory experiments the role of horizontally polarized light in the selection of oviposition sites in blood-fed, gravid females of the yellow fever mosquito, Aedes aegypti. On the basis of our results we propose that Ae. aegypti is not polarotactic. Thus the yellow fever mosquito is the first known water-associated insect species that does not detect water by means of the horizontally polarized water-reflected light. This can be explained by the reflection–polarization characteristics of small-volume water-filled cavities/containers preferred by Ae. aegypti as oviposition sites. [Copyright &y& Elsevier]

1. We observed that the dragonfly species Sympetrum flaveolum, S. striolatum, S. sanguineum, S. meridionale and S. danae were attracted by polished black gravestones in a Hungarian cemetery. 2. The insects showed the same behaviour as at water: (i) they perched persistently in the immediate vicinity of the chosen gravestones and defended their perch against other dragonflies; (ii) flying individuals repeatedly touched the horizontal surface of the shiny black tombstones with the ventral side of their body; (iii) pairs in tandem position frequently circled above black gravestones. 3. Tombstones preferred by the dragonflies were in the open and had an area of at least 0.5 m2 with an almost horizontal, polished, black surface and with at least one perch in their immediate vicinity. 4. Using imaging polarimetry, we found that the black gravestones, like smooth water surfaces, reflect highly and horizontally polarized light. 5. In double-choice field experiments with various test surfaces, we showed that the dragonflies attracted to shiny black tombstones display positive polarotaxis and, under natural conditions, detect water by means of the horizontally polarized reflected light. This, and the reflection-polarization characteristics of black gravestones, explain why these dragonflies are attracted to black tombstones. 6. If females attracted to the black gravestones oviposit on them, the latter constitute ecological traps for dragonflies that are not close to water. [ABSTRACT FROM AUTHOR]