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A study was carried out at an organic buffalo dairy farm in order to investigate the effect of feeding protein peas (Pisum sativum L.) as an alternative protein source for buffalo cow diets. Two concentrates were formulated to contain (as fed basis) either 350 g/kg of soybean cake (SC) or 450 g/kg of peas (PC) as the main protein sources. The two concentrates were formulated to be almost isonitrogenous (on average crude protein 240 g/kg DM). Two groups of 10 buffalo cows were used in a 100-day lactation study (from 10 days in milk onwards). Cows were blocked into two groups according to lactation number and previous milk yield and were assigned to one of two dietary treatments: control group was offered in the milking parlour 3 kg of SC, while treatment group was offered the same quantity of PC. All cows were fed a total mixed ration containing 3 kg of SC. Daily milk yield was not affected by treatment, as well as, milk fat and protein percentages, somatic cell count, urea content and fatty acid composition.

This paper compares the performance of three novel biodegradable films having different gas and water vapour permeabilities to the performance of a multilayer film made of polyethylene and EVOH and having high barrier properties. As model food C. Pugliese cheese was chosen. The samples were stored for 28 days and, once a week, they were analysed using sensory and instrumental tests. Sensory data showed samples packed in high permeable biodegradable film were different from fresh cut samples after only 7 days of storage, whereas the other biodegradable films having intermediate water vapour permeability allowed the cheese to keep its sensory properties unchanged for 21 days. The only film which maintained the sensory properties of cheese, with except for texture, during all the investigated time, was the high barrier film. The sensory data are confirmed by acceptability scores.

We analyze from a computational viewpoint the conformational and dynamical properties of the interesting oligopeptide that is reported to bind specifically to titania surfaces. First-principles simulations based on Density Functional Theory (DFT) and classical Molecular Dynamics (MD) are carried out to investigate both the structure and the stability of single amino acids and of the full peptide on the (101) surface of TiO2 in the anatase crystalline structure. Moreover the strength of the adhesion is estimated by pulling the peptide away from the surface. Our results shed light on the role played by some amino acids that are known to be essential in selective adsorption on TiO2, as well as on the peptide structural conformation upon the surface.Copyright © 2013 American Scientific Publishers.

The structural and electronic properties of both inorganic and hybrid organic-inorganic perovskites based on tin halides are investigated from the first principles. In particular, we contrast the inorganic ${\text{CsSnCl}}_{3}$ and ${\text{CsSnI}}_{3}$ to their hybrid counterparts $({\text{CH}}_{3}{\text{NH}}_{3}){\text{SnCl}}_{3}$, $({\text{CH}}_{3}{\text{NH}}_{3}){\text{SnI}}_{3}$, and $({\text{NH}}_{2}\text{CH}={\text{NH}}_{2}){\text{SnI}}_{3}$, which were obtained by substituting the inorganic Cs cation with the methylammonium ${\text{CH}}_{3}{\text{NH}}_{3}$ and the formamidinium ${\text{NH}}_{2}\text{CH}={\text{NH}}_{2}$ cations. The comparison between the hybrid perovskites and the inorganic counterparts sheds light on the effects of the filling molecule on the structural and electronic properties of the compound. We show that the stability against the distortion of the perovskitic cage strongly depends on the embedded cation. The electronic properties (in particular, the band gap) can be tuned by a suitable choice of the organic molecule, and, in particular, of its size.

Well-oriented thin films of methyl-ammonium trihalogenostannates CH3NH3SnX3 compounds (X=Cl,Br) are grown by the single source thermal ablation technique. Optical absorption and structural analysis of CH3NH3SnX3 thin films are combined with ab initio calculations in order to clarify their electronic properties and the role of the organic cation. The structural calculations reproduce well the measured lattice parameters, and optical measurements reveal a direct gap absorption onset for both compounds, in agreement with the calculated band structures. It turns out from projected density of states analysis that the valence and conduction bands take negligible contribution from the methylammonium. It is inferred that the band gap mainly depends on the ionicity and size of the inorganic cage SnX3.

The effect of organic adsorbates on the silicon (001) surface is investigated using first-principles calculations. Ethylene and a class of cyclopentene derivatives, containing different functional groups, are considered, all anchoring to the surface through the same $[2+2]$ cycloaddition mechanism. Because they all show similar bonding properties, any variation in the surface properties must be related to the functional group. The structural relaxation induced by the adsorption is discussed, elucidating the effect of both the adsorbate species and coverage. It turns out that different distortions occur in the molecular geometry, depending on both the species and the surface coverage, while molecule-to-surface bonding does show very similar features for all the considered molecules. We show that the presence of the adsorbate can modify the surface charge density, thus giving rise to an induced dipolar layer that modifies the electrostatic potential outside the surface. Such a dipole layer can, in turn, be related to surface electron affinity and work function changes. A careful analysis of the dipole moment and of the electrostatic potential changes is carried out discussing the correlations with the properties of the isolated molecules. All the results indicate how the surface properties can be tuned through a suitable choice of the adsorbate.