Conformational Selection in Glycomimetics: Human Galectin‐1 Only Recognizes syn‐Ψ‐Type Conformations of β‐1,3‐Linked Lactose and Its C‐Glycosyl Derivative

The human lectin galectin‐1 (hGal‐1) translates sugar signals, that is, β‐galactosides, into effects on the level of cells, for example, growth regulation, and has become a model for studying binding of biopharmaceutically relevant derivatives. Bound‐state conformations of Galβ‐C‐(1→3)‐Glcβ‐OMe ( 1 ) and its βGal‐(1→3)‐βGlc‐OMe disaccharide parent compound were studied by using NMR spectroscopy (transferred (TR)‐NOESY data), assisted by docking experiments and molecular dynamics (MD) simulations. The molecular recognition process involves a conformational selection event. Although free C‐glycoside access four distinct conformers in solution, hGal‐1 recognizes shape of a local minimum of compound 1 , the syn‐Φ/syn‐Ψ conformer, not the structure at global minimum. MD simulations were run to explain, in structural terms, the observed geometry of the complex.     

Joaquin Sorolla's pigment characterisation of the paintings ‘Vision of Spain’ by means of EDXRF portable system

In this work, portable energy dispersive X‐ray fluorescence (EDXRF) spectrometry was employed to the characterisation of the palette used by the Spanish artist Joaquín Sorolla (1863–1923) in the paintings ‘Vision of Spain’, a set of 14 oils on canvas painted by Sorolla between 1911 and 1919 by order of Mr Archer Huntington to decorate the library of the Hispanic Society of America (HSA) in New York. The analyses, sponsored by BANCAJA and provided by the HSA, were carried out in situ, prior to the cleaning and restoration process, while the paintings hanging on the walls of the library of the HSA. The results revealed that the paintings were made over different priming layers containing, respectively, lead white, zinc and barium compounds, lead white mixed with zinc white or lead white mixed with zinc and barium compounds. The EDXRF analyses of coloured zones identified up to 29 inorganic pigments and, in some cases, the probable use of organic pigments. Sorolla used traditional pigments as earth pigments, lead white, vermillion, etc., and modern pigments as cadmium yellow, zinc white, cobalt‐based blue, chromium‐based green, manganese‐based violet, etc. These results provide valuable information about the Sorolla's palette during the last stage of his life. Copyright © 2011 John Wiley & Sons, Ltd.     

New Advances in Protection Against Solar Ultraviolet Radiation in Textiles for Summer Clothing

Clothing is considered one of the most important tools for photoprotection against harmful solar ultraviolet radiation (UVR). The standard for sun‐protective clothing is based on erythema despite other biological effects of UVR on the skin. We analyzed the potential protection against UVR in fabrics destined for summer clothing based on several action spectra. We examined 50 garments classified by type of fabric composition, structure of the fiber yarn and color. The ultraviolet protection factor was calculated based on fabric ultraviolet transmittance corrected for erythema according to the EU standard E‐13758 as well as the UVA transmittance of fabrics. UVR protection was also analyzed in base of different action spectra as for previtamin D3, nonmelanoma skin cancer, photoimmunosuppression and photoaging. Most knitted fabrics used for sports T‐shirts offered excellent ratings for ultraviolet protection while normal shirts showed very low ratings, particularly against photoaging. The cover is the most influential variable in fabric photoprotection, having an exponential relationship with the UPF. The relation between cover and UVA protection was linearly negative. Information about ultraviolet protection in textiles used for summer clothing should be included in labeling as some types of fabrics, especially those used for shirts, offer very low UVR protection.     

Density functional studies of coinage metal nanoparticles: scalability of their properties to bulk

Density functional plane-wave calculations have been carried out for series of Cu _n ,Ag _n and Au _n particles containing up to 146 (Cu, Ag) and 225 (Au) atoms. Full geometry optimization has been performed for all particles starting from the structures created by cuts from the bulk. In line with previous studies, calculated average nearest-neighbour distances and cohesive energies of the particles linearly depend on such size-derived parameters as the average coordination number of metal atoms and the inverse of the mean particle radius, respectively. Rather accurate linear extrapolation of the observables under scrutiny to the bulk values has been achieved. However, we show that the scalability for particles made of various elements of the same d¹⁰s¹ electron configuration differs, e.g. for bond lengths in Au _n species it is noticeably less perfect than that for Cu _n and Ag _n ones. Implications of encountered structural peculiarities of the nanoparticles for their reactivity are outlined.     

Line transversals to blown up closed balls

The number ?? _d (k) is defined as the minimum ???>?0 such that the following holds: For any finite family ${\mathcal {F}=\{B_1,B_2, \ldots , B_n\}}$ of closed balls in ${{\mathbb{R}}^d}$ such that every k elements of ${\mathcal {F}}$ have a common line transversal, the elements of the blown up family ${\lambda\mathcal {F}=\{\lambda B_1,\lambda B_2, \ldots , \lambda B_n\}}$ have a common line transversal. In this paper we show that ${\lambda_d(d+1)\leq4, \lambda_2(4)\leq 2\sqrt 2}$ and ??₂(3)?<?2.88.     

Line Transversals to Translates of a Convex Body

Let K be a convex body in the plane. Define λ(K,t) as the smallest number satisfying the following: if F\mathcal{F} is any family of translates of K such that every t members of F\mathcal{F} have a common transversal, then all the members of l(K,t)F\lambda(K,t)\mathcal{F} have a common transversal. We give bounds for λ(K,3) and λ(K,4) for a general convex figure K. In particular, we obtain that λ(K,3)≤1.79 when K is the Euclidean disc.     

Assessment of terahertz spectroscopy to detect antibiotic residues in food and feed matrices

We report the use of terahertz (THz) spectroscopy to explore the spectral properties of eleven antibiotics commonly used in livestock production. Eight of the eleven antibiotics showed specific fingerprints in the frequency range between 0.1 and 2 THz. The main spectral features of two antibiotics (doxycycline and sulfapyridine) were still detectable when they were mixed with three food matrices (feed, milk, and egg powder). These preliminary results indicate that THz spectroscopy could be suitable for screening applications to detect the presence of antibiotic residues in the food industry, with the prospect to allow inspections directly on the production lines. THz spectroscopy is a non-destructive, non-contact, and real-time technique that requires very little sample preparation. Moreover, THz radiation can penetrate plastic and paper, which enables the detection of antibiotics in packaged food.     

Control of nitrogen insertion during the growth of nitrogen-containing carbon nanofibers on cordierite monolith walls

A well attached coating of nitrogen-functionalised carbon nanofibers (N-CNFs) has been prepared on the walls of cordierite monolith channels. It is formed via concurrent decomposition of ethane and ammonia catalysed by nickel nanoparticles dispersed on alumina coated cordierite monolith. N-CNF/monoliths synthesis employing several growth temperatures and NH(3) compositions was exhaustively characterised by Raman, XPS, elemental analysis and TEM. Synthesis conditions affected profoundly content and type of nitrogen functionality, enabling its fine tuning. N-CNFs surface chemistry and microstructure differed remarkably from its N-free counterparts.