Properties of the inner penumbral boundary and temporal evolution of a decaying sunspot

It was empirically determined that the umbra-penumbra boundaries of stable sunspots are characterized by a constant value of the vertical magnetic field. We analyzed the evolution of the photospheric magnetic field properties of a decaying sunspot belonging to NOAA 11277 between August 28 - September 3, 2011. The observations were acquired with the spectropolarimeter on-board of the Hinode satellite. We aim to proof the validity of the constant vertical magnetic-field boundary between the umbra and penumbra in decaying sunspots. A spectral-line inversion technique was used to infer the magnetic field vector from the full-Stokes profiles. In total, eight maps were inverted and the variation of the magnetic properties in time were quantified using linear or quadratic fits. We found a linear decay of the umbral vertical magnetic field, magnetic flux, and area. The penumbra showed a linear increase of the vertical magnetic field and a sharp decay of the magnetic flux. In addition, the penumbral area quadratically decayed. The vertical component of the magnetic field is weaker on the umbra-penumbra boundary of the studied decaying sunspot compared to stable sunspots. Its value seem to be steadily decreasing during the decay phase. Moreover, at any time of the shown sunspot decay, the inner penumbra boundary does not match with a constant value of the vertical magnetic field, contrary to what was seen in stable sunspots. During the decaying phase of the studied sunspot, the umbra does not have a sufficiently strong vertical component of the magnetic field and is thus unstable and prone to be disintegrated by convection or magnetic diffusion. No constant value of the vertical magnetic field was found for the inner penumbral boundary.Comment: Accepted for publication in Astronomy & Astrophysics, 6 pages, 7 figure

Plant immunity and beyond: Signals from proteins & peptides

Plants are the primary and most important source of food for human consumption, besides their ecological importance, since they define the diverse ecosystems worldwide. Because of their position in the ecological chain as primary supplier of biomass and food for other organisms, plants are also fundamental for animals, fungi and microorganisms, and some of them are also beneficial to other plants. Humans rely mostly on plant products for food, and many plants provide important non-food products, including wood, textiles, medicines, cosmetics, soaps, rubber, plastics, paints and other industrial chemicals. Moreover, plants are also fundamental for animal feeding, including not only mammals (e.g. cattle, sheep and goats), but also poultry and aquaculture (e.g., fish and shrimp farming)

Xtru3D: Single-View 3D Object Reconstruction from Color and Depth Data

D object reconstruction from single image has been a noticeable research trend in recent years. The most common method is to rely on symmetries of real-life objects, but these are hard to compute in practice. However, a large class of everyday objects, especially when manufactured, can be generated by extruding a 2D shape through an extrusion axis. This paper proposes to exploit this property to acquire 3D object models using a single RGB+Depth image, such as those provided by available low-cost range cameras. It estimates the hidden parts by exploiting the geometrical properties of everyday objects, and both depth and color information are combined to refine the model of the object of interest. Experimental results on a set of 12 common objects are shown to demonstrate not only the effectiveness and simplicity of our approach, but also its applicability for tasks such as robotic grasping.The research leading to these results has been funded by the HANDLE European project (FP7/2007-2013) under grant agreement ICT 231640-http://www.handle-project.eu.Publicad

Haem Accessibility in Monomeric Haemoglobins of Glycera dibranchiata and Petromyzon marinus, a Proton Magnetic Relaxation Study

The temperature dependence of the longitudinal magnetic relaxation rates of water protons in solutions of differently liganded monomeric haemoglobins from Petromyzon marinus (fraction V) and Glycera dibranchiata (fraction III) was measured. The results were compared with horse and bovine myoglobins and interpreted according to the model of chemical exchange of water molecules. This exchange takes place between a site within the haem-pocket (but non-identical to the sixth-ligand position) and the bulk of the solvent. Aquomethaemoglobin from Glycera dibranchiata only slightly enhances the relaxation rates of water protons between O 0c and 40 °c and pH between 5.85 and 7.0. This finding is compatible with tight protein packing around the distal side of the haem. In the solutions of aquomethaemoglobin from Petromyzon marinus up to 30 °c, the solvent-proton relaxation rates are determined by the rate of chemical exchange of water molecules. At higher temperatures the fast exchange mechanism takes place, an effect not observed in solutions of horse and bovine myoglobins. The distance of closest approach of water protons to the ferric ion of Petromyzon haemoglobin is at least 0.3 A longer than in mammalian myoglobins. Binding of fluoride to the ferric haem-irons of all the haemoglobins examined thus far enhances the proton relaxation rates relative to their aquomet forms, while in their nitrosyl complexes slightly lower rates were measured. These data indicate the sensitivity of the protein structure to the nature of the sixth ligand. The accessibility of the unpaired electron(s) in all the haemoglobins examined is in the order: NO-< aquomet- < fluoromet-forms. From our previous and present data and from that found in literature, a scale of accessibilities of the ferric haem-irons for the exchangeable water molecules is compiled

Hepatic Cytochrome P-450. A Proton Magnetic Relaxation Study of Microsomal, Solubilized and Partially Reconstituted Enzyme System

The longitudiJ:ial proton magnetic relaxation times, Ti, were measured from -5 to 40 °c for microsomal, solubilized and reconstituted cytochrome P-450 obtained from phenobarbital-induced rat livers. The paramagnetic contribution to the rates was derived by subtraction of the rates measured on dithionite-CO-reduced samples. The same values were obtained for microsomal P-450 on reduction with NADPH. PMR titratio.n by KCN yielded a dissociation constant of about 30 mM. This is three orders of magnitude larger than for metmyoglobin. It is concluded that the measured PMR rates are most likely due to the P-450 (and P-420) haem-iron while the 300/o non-haem iron found in both the microsomal and s olubilized P-450 is .ineffective for the PMR rates. These rates increase several times on isotopic dilution (D20 for H20) with the microsomes and diminish for the solubilized samples. Microsomes show 170/o residual, encaged, H20. Most of their paramagnetic PMR rate is due to the parama.gnetic iron located on the outside of microsomes. This is demonstrated by measurements with deuterated samples to which 190/o H20 had been added. Hence, the solubilized P-450 is homogeneous regarding PMR, but the microsomes are not

Five colour photometry of the RRd star V372 Ser

The first UBV(RI)_C time series photometry of the RRd star V372 Ser is presented to determine some parameters of the star. In April, May 2007 2812 U, B, V, R_C, I_C frames were obtained at Konkoly and Teide Observatories, 1508 V observations were collected from the literature. Fourier fitted light curves have been derived in all bands. The non-linearly coupled frequencies f_0=(2.121840+/-.000001) c/day, f_1=(2.851188+/-.000001) c/d, i.e. periods P_0=0.4712891+/-.0000002 days, P_1=0.3507310+/-.0000001 d, P_1/P_0=0.7441950, amplitudes A_0(V)=0.15399 mag, A_1(V)=0.20591 mag, and phases have been found. A_1/A_0=1.319+/-.008 has been found from averaging the amplitude ratio in the different bands i.e. the first overtone is the dominant pulsation mode. From the V observations upper limits are given for secular change of the Fourier parameters. The period ratio and period put V372 Ser among the RRd stars of the globular clusters M3 and IC 4499, mass, luminosity, and metallicity estimates are given.Comment: accepted by Astronomy and Astrophysics (5 pages, 3 figures, 4 tables