The essential oil of Thymbra capitata and its application as a biocide on stone and derived surfaces

Many chemicals used nowadays for the preservation of cultural heritage pose a risk to both human health and the environment. Thus, it is desirable to find new and eco-friendly biocides that can replace the synthetic ones. In this regard, plant essential oils represent effective alternatives to synthetic substances for the preservation of historical monuments. Thymbra capitata (syn. Thymus capitatus) is a medicinal and aromatic plant growing in the Mediterranean area and endowed with important pharmacological properties related to its essential oil. Among them, the antimicrobial ones make the T. capitata essential oil an ideal candidate for industrial applications; for instance, as biocide for the inhibition and elimination of biological patinas of cyanobacteria and green algae on historical monuments. In the present work, we studied the chemical composition of the essential oil from T. capitata growing in Malta by gas chromatography-mass spectrometry (GC/MS). The major volatile component is the phenolic monoterpene carvacrol (73.2%), which is capable of damaging the cytoplasmic membrane and to interfere both in the growth curve and in the invasive capacity, though the contribution of minor components γ-terpinene and p-cymene cannot be disregarded. For the oil application on the stone surface, Pickering emulsions systems were prepared with an essential oil/water 1:3 mass ratio stabilized with kaolinite at 4 mass% in the presence of Laponite®; this allowed to limit the fast volatility of the oil and guaranteed a better application and an easier removal from the artefacts attacked by biodeteriogens both indoor and outdoor. This formulation caused the elimination of biodeteriogens from treated surfaces without residuals or films on artworks surface, and the effect was retained up to four months

Clashes and Compromises: Investment Policies in Tourism Destinations

The authors solve a linear problem where a potential conflict between two agents (Destination manager and Firm) arises in a tourism destination. The Destination manager has to choose how to allocate limited resources (capital and land) between either second homes or hotels. This conflict stems from the assumption of agents who have different linear preferences with respect to the allocation of limited resources. As a solution to this policy problem the authors consider three different policies: no intervention (laissez faire), taxation and temporary de-taxation policy. Comparing these different policies, they show that a compromise solution (internal solution), which results from the de-taxation policy, may be preferred by both agents over the clash of interests outcomes (corner solutions). Thus, the authors show that in a framework of \u201cconflict\u201d between agents a compromise solution may be preferable to both the absence of public intervention and the imposition of a tax by a public policy maker who has the discretionary \u201cpower to regulate\u201d conflicts

Optical Properties of Graphene Nanoflakes: Shape Matters

In recent years there has been significant debate on whether the edge type of graphene nanoflakes (GNF) or graphene quantum dots (GQD) are relevant for their electronic structure, thermal stability and optical properties. Using computer simulations, we have proven that there is a fundamental difference in the calculated absorption spectra between samples of the same shape, similar size but different edge type, namely, armchair or zigzag edges. These can be explained by the presence of electronic structures near the Fermi level which are localized on the edges. These features are also evident from the dependence of band gap on the GNF size, which shows three very distinct trends for different shapes and edge geometries.Comment: 8 pages, 9 figures. Submitted to The Journal of Chemical Physic

Nonparametric Bayesian Mixed-effect Model: a Sparse Gaussian Process Approach

Multi-task learning models using Gaussian processes (GP) have been developed and successfully applied in various applications. The main difficulty with this approach is the computational cost of inference using the union of examples from all tasks. Therefore sparse solutions, that avoid using the entire data directly and instead use a set of informative "representatives" are desirable. The paper investigates this problem for the grouped mixed-effect GP model where each individual response is given by a fixed-effect, taken from one of a set of unknown groups, plus a random individual effect function that captures variations among individuals. Such models have been widely used in previous work but no sparse solutions have been developed. The paper presents the first sparse solution for such problems, showing how the sparse approximation can be obtained by maximizing a variational lower bound on the marginal likelihood, generalizing ideas from single-task Gaussian processes to handle the mixed-effect model as well as grouping. Experiments using artificial and real data validate the approach showing that it can recover the performance of inference with the full sample, that it outperforms baseline methods, and that it outperforms state of the art sparse solutions for other multi-task GP formulations.Comment: Preliminary version appeared in ECML201

DERIVAZIONE DI IDROGRAMMI DI PIENA ATTRAVERSO L\u2019ACCOPPIAMENTO DI MODELLI STOCASTICI BIVARIATI DELLE PRECIPITAZIONI E E MODELLI AFFLUSSI - DEFLUSSI DISTRIBUTI

In questo studio viene presentata una procedura di tipo Monte Carlo per la derivazione delle curve di frequenza delle portate al colmo e dei volumi corrispondenti basata sull\u2019accoppiamento di un modello di generazione delle forzanti pluviometriche tramite copule e un modello di trasformazione afflussideflussi di tipo distribuito. Tale procedura \ue8 stata applicata ad un caso di studio siciliano; i risultati ottenuti hanno mostrato la bont\ue0 del modello a riprodurre le statistiche complesse delle grandezze idrologiche a fronte di un basso numero di parametri modellistici e di un ridotto sforzo computazionale

Optimal Surface Drainage Inlets Positioning Using Stochastic Pluvial Flooding Analysis

Source: ICHE Conference Archive - https://mdi-de.baw.de/icheArchive

Hsp70 localizes differently from chaperone Hsc70 in mouse mesoangioblasts under physiological growth conditions.

Mouse A6 mesoangioblasts express Hsp70 even in the absence of cellular stress. Its expression and its intracellular localization were investigated under normal growth conditions and under hyperthermic stress. Immunofluorescence assays indicated that without any stress a fraction of Hsp70 co-localized with actin microfilaments, in the cell cortex and in the contractile ring of dividing cells, while the Hsc70 chaperone did not. Hsp70 immunoprecipitation assays confirmed that a portion of Hsp70 binds actin. Immunoblot assays showed that both proteins were present in the nucleus. After heat treatment Hsp70 and actin continued to co-localize in the leading edge of A6 cells but not on microfilaments. Although Hsp70 and Hsc70 are both basally synthesized they showed different cellular distribution, suggesting an Hsp70 different activity respect to the Hsc70 chaperone. Moreover, we found Hsp70 in the culture medium as it has been described in other cell types

Interstitial gas and density-segregation in vertically-vibrated granular media

We report experimental studies of the effect of interstitial gas on mass-density-segregation in a vertically-vibrated mixture of equal-sized bronze and glass spheres. Sufficiently strong vibration in the presence of interstitial gas induces vertical segregation into sharply separated bronze and glass layers. We find that the segregated steady state (i.e., bronze or glass layer on top) is a sensitive function of gas pressure and viscosity, as well as vibration frequency and amplitude. In particular, we identify distinct regimes of behavior that characterize the change from bronze-on-top to glass-on-top steady-state.Comment: 4 pages, 5 figures, submitted to PRL; accepted in PRE as rapid communication, with revised text and reference

Evans Syndrome: A case report

Evans syndrome, a combined clinical condition of autoimmune haemolytic anaemia (AHA) and idiopathic thrombocytopaenic purpura (ITP) and has non-specific pathogenesis. The clinical cases are extremely rare, since only 4% of AHA or ITP are incorporated with Evans. It is distinguished from differentials, such as lupus, IgA deficiency, and acquired immunodeficiency, by peripheral blood film, bone marrow, Coombs test, and coagulation profile. A case of adult female from Pabna, Bangladesh is documented in this report. She complained of high grade intermittent fever, exertional dyspnea, icteric skin and sclera. Other features included mild splenomegaly, dark urine, and profuse sweating after fever. Investigation reports were consistent with AHA and ITP, with normal coagulation and viral profile. However, the patient was treated with corticosteroids, platelet and blood transfusion. And in follow-up visits, there was a pattern of gradual decline in erythrocyte sedimentation rate (ESR) and reticulocyte count, with normalization of haemoglobin, red cell, and white cell count. No association with other diseases was found in this case. Bangladesh Med J. 2018 Jan; 47 (3): 37-4