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We consider an inverse problem for Schrödinger operators on a connected equilateral graph G with standard matching conditions. The graph G consists of at least two odd cycles glued together at a common vertex. We prove an Ambarzumian-type result, i.e., if a specific part of the spectrum is the same as in the case of zero potential, then the potential must be equal to zero. [ABSTRACT FROM AUTHOR]

Lepidoptera is one of the most diverse orders of insects, their larvae are very abundant in many habitats, and frequent prey of various predators. To decrease predation risk, caterpillars developed several means of defence, among them timing their activity to avoid predators (seeking enemy-free time). Although the enemy-free time hypothesis is often invoked to explain caterpillar behaviour, empirical evidence for it is scarce. We tested whether such enemy-free time exists in a temperate forest by comparing predation pressure on artificial caterpillars during day and night on the ground in forest fragments in Denmark. We found a high predation rate, 23.9%d-1, and higher predation rate at night (30.9%d-0.5) than during the day (17.0%d-0.5), both by invertebrate (23.3%d-0.5 vs. 12.4%d-0.5) and vertebrate (8.5%d-0.5 vs. 3.3%d-0.5) predators. The most important predators were chewing insects (73.4% of all attacks) and small mammals (19.0%). Attack rates on red caterpillars were higher (30.0%d-1) than on green ones (19.5%d-1). Overall, these data do not support the idea that night activity can provide enemy-free time for solitary caterpillars on the temperate forest floor. [ABSTRACT FROM AUTHOR]

We consider an inverse eigenvalue problem for Dirac operators on finite intervals. We show that if for a $${\mu\in\mathbb{C}}$$ the system $${\{\exp{2i\lambda_nx}}$$ , $${\exp{2i\mu x}\}}$$ is closed in $${L^p[-\pi,\pi]}$$ , then there is at most one $${L^p}$$ -potential with the eigenvalues $${\lambda_n}$$ . The result corresponds to the case of Schrödinger operators. [ABSTRACT FROM AUTHOR]

Infrasound measurements are used to detect seismic waves and a large effort is devoted to eliminating the turbulence-related infrasound signal, usually considered as noise. Here we take a complementary approach, investigating whether infrasound can provide information on atmospheric turbulence. Microphone measurements of infrasound from an experimental campaign in Hungary in 2013 are used, together with data from a nearby sonic anemometer and a sodar. The comparison of infrasound integrated spectral energy to turbulent kinetic energy from the sonic provides a good match when turbulence is present near the ground. Moreover, on stable nights when the surface layer is strongly stratified and with turbulence absent, microphones sometimes recorded infrasound when the sodar showed a low-level jet above the surface inversion, indicating that microphones may be used as detectors of elevated turbulence. [ABSTRACT FROM AUTHOR]

In the 50 years since the advent of X-ray astronomy there have been many scientific advances due to the development of new experimental techniques for detecting and characterising X-rays. Observations of X-ray polarisation have, however, not undergone a similar development. This is a shortcoming since a plethora of open questions related to the nature of X-ray sources could be resolved through measurements of the linear polarisation of emitted X-rays. The PoGOLite Pathfinder is a balloon-borne hard X-ray polarimeter operating in the 25-240 keV energy band from a stabilised observation platform. Polarisation is determined using coincident energy deposits in a segmented array of plastic scintillators surrounded by a BGO anticoincidence system and a polyethylene neutron shield. The PoGOLite Pathfinder was launched from the SSC Esrange Space Centre in July 2013. A near-circumpolar flight was achieved with a duration of approximately two weeks. The flight performance of the Pathfinder design is discussed for the three Crab observations conducted. The signal-to-background ratio for the observations is shown to be 0.25 ±0.03 and the Minimum Detectable Polarisation (99 % C.L.) is (28.4 ±2.2) %. A strategy for the continuation of the PoGOLite programme is outlined based on experience gained during the 2013 maiden flight. [ABSTRACT FROM AUTHOR]

Thermal stability and internal dynamics of myosin head in psoas muscle fibres of rabbit in the intermediate state AM.ADP.Pi - mimicked by AM.ADP.Vi - of the ATP hydrolysis cycle was studied by differential scanning calorimetry and spin label electron paramagnetic resonance spectroscopy. Three overlapping endotherms were detected in rigor, in strongly binding ADP and weakly binding AM.ADP.Vi state of myosin to actin. The transition at 54.0°C can be assigned to the 50 k actin-binding domain. The transition at highest temperature (67.3°C) represents the unfolding of actin and the contributions arising from the nucleotide-myosin head interaction. The transition at 58.4°C reflects the melting of the large rod part of myosin. Nucleotide binding (ADP, ATP plus orthovanadate) induced shifts of the melting temperatures and produced changes in the calorimetric enthalpies. The changes of the EPR parameters indicated local rearrangements of the internal structure in myosin heads in agreement with DSC findings. [ABSTRACT FROM AUTHOR]

Differential scanning calorimetry and electron paramagnetic resonance experiments were performed on glycerinated skeletal muscle fibres to study the effect of the binding of nucleotides and nucleotide analogues to myosin. The thermal unfolding of muscle fibres in rigor showed three discrete domain regions with thermal stability of 52.2, 58.8 and 67.8°C. AMP.PNP and ATP plus AlF3 or BeF2 affected markedly the transitions, which implies the strong interaction between AMP.PNP or nucleotide analogues and catalytic domain of myosin, and a partial dissociation of heads from actin. ADP.BeFx and states model the transition states of the ATP hydrolysis cycle which precede the powerstroke of the muscle fibres. Spectrum deconvolution on isothiocyanate-labelled fibres in AMP.PNP-state resulted in two populations; 50% of labels was highly ordered with respect to fibre axis, whereas the other 50% of labels was randomly oriented. The myosin heads which showed high degree of order were in the strongly binding ADP-state. The spectra in - and ADP.BeFx state reflected random orientation of labels with increased rotational mobility in comparison with rigor. The results suggest that myosin in muscle fibres in ADP.BeFx state exists in two forms. [ABSTRACT FROM AUTHOR]

The effect of free radicals obtained in hydroxyl and cerium(IV)-nitrilotriacetic acid free radical generating systems on contractile proteins (actin, myosin and their complexes in glycerinated muscle fibres) was studied using differential scanning calorimetry and spin trapping electron paramagnetic resonance technique. The analysis of spectra showed that selective attack of thiol groups – Cys-257 and Cys-374 residues of actin, and among others Cys-707 residue of myosin – and random attack of sidechains of the main proteins of muscle tissue produced structural and functional changes, which affected the ATP hydrolysis cycle and very likely the dynamics of actin. The melting curves obtained on protein systems support the view that global conformational changes accompany the local damage of free radicals. [ABSTRACT FROM AUTHOR]

Objective: Dithranol is highly effective in the treatment of psoriasis, however its mode of action is still not well known. Since interleukin-8 and interleukin-10 are involved in the pathogenesis of psoriasis, the aim of our study was to investigate the effect of dithranol on interleukin-8, interleukin-10 mRNA production and interleukin-10 receptor expression of the HaCaT keratinocyte cell line which is commonly used in experiments examining the effects of therapeutic drugs on keratinocytes.¶ Materials and Methods: Cultured HaCaT cells were treated with 0.1-0.5 μg/ml dithranol for 30 minutes. After 2 and 4 h total cellular RNA isolated from HaCaT cells was reverse transcribed (RT) to cDNA which was subjected to polymerase chain reaction (PCR) with specific primer pairs for interleukin-8, interleukin-10 and interleukin-10 receptor. For immunohistochemistry cultured HaCaT cells were stained with a monoclonal antibody against the human interleukin-10 receptor.¶ Results: Our results showed that dithranol treatment did not change the highly elevated level of interleukin-8 mRNA of HaCaT cells. Interleukin-10 mRNA signal with RT-PCR could not be detected in HaCaT cells. Depending on the concentration dithranol increased the mRNA production of interleukin-10 receptors in HaCaT cells. This dithranol induced dose dependent upregulation of IL-10 receptors in HaCaT cells was also observed on the protein level using immunohistochemistry.¶ Conclusions: Since the interleukin-10 receptor expression of keratinocytes in psoriatic lesional skin is downregulated, the dithranol induced upregulation of the receptor in our model system might help to reveal the therapeutic action of the drug.¶ [ABSTRACT FROM AUTHOR]

We report five patients with moyamoya associated with arterial anomalies, including five aneurysms, one with ectasia of the parent artery, a basilar artery fenestration and an arteriovenous malformation. Possible pathogenetic factors for moyamoya are discussed, and a prenatal origin is suggested. [ABSTRACT FROM AUTHOR]

In order to reveal the actual effects of common reed (Phragmites australis (Cav) Trin. ex Steudel) and its periphyton complex on the water quality, studies on the heavy metal contents of common reed and itsperiphyton are important. This paper discusses the results of studies on heavy metal contents of the host plant-periphyton complex carried out in Lake Balaton, Lake Velence, Lake Ferto and Kis-Balaton Reservoir. A second goal was to study the effects of reed stands in different condition (healthy, transitional, die-back) on the structure of its periphyton and their role in water quality indication. Simultaneously with the reed and periphyton sampling, water samples were taken for investigation. We determined the wet mass of periphyton and after drying at 105 deg. C; the dry mass was measured and ash contents of reed and its periphyton samples were also determined. The concentration of 27 (Na, Mg, Ca, K, Zn, Cu, Cd, Cr, Pb, Mo, etc.) cations was determined from the reed, periphyton and water samples by ICP-AES method. The heavy metal content of reed and periphyton was especially high at places impacted by high anthropogenic loadings. On the basis of our results, the biofilter role of periphyton-reed complex can be confirmed. Since the main reasons of reed decline have not been revealed, future research has to focus on involving reed-periphyton studies also, which may provide good basis to find the most appropriate ways to protect and restore the reed communities of shallow standing waters. [ABSTRACT FROM AUTHOR]