Terrain classification by cluster analisys

The digital terrain modelling can be obtained by different methods belonging to two principal categories: deterministic methods (e.g. polinomial and spline functions interpolation, Fourier spectra) and stochastic methods (e.g. least squares collocation and fractals, i.e. the concept of selfsimilarity in probability). To reach good resul ts, both the fi rst and the second methods need same initial suitable information which can be gained by a preprocessing of data named terrain classification. In fact, the deterministic methods require to know how is the roughness of the terrain, related to the density of the data (elevations, deformations, etc.) used for the i nterpo 1 at ion, and the stochast i c methods ask for the knowledge of the autocorrelation function of the data. Moreover, may be useful or very necessary to sp 1 it up the area under consideration in subareas homogeneous according to some parameters, because of different kinds of reasons (too much large initial set of data, so that they can't be processed togheter; very important discontinuities or singularities; etc.). Last but not least, may be remarkable to test the type of distribution (normal or non-normal) of the subsets obtained by the preceding selection, because the statistical properties of the normal distribution are very important (e.g., least squares linear estimations are the same of maximum likelihood and minimum variance ones)

Bisogna portare il pensiero della morte come i signori della epoca portavano il falcone sulla spalla.

Il titolo è tratto da un pensiero, forse un poco conturbante, ma certamente necessario, di Michel Eyquem de Montaigne e serve per fare un bilancio onesto. Infatti la scelta di essere agnostici qualifica coloro che scrivono come scettici e relativisti moderati, riducendo molti loro pensieri al solo strumentalismo operazionale, proposto da Percy Williams Bridgman. A riguardo, importante è la critica delle metodologie e procedure, comunemente impiegate, e come cautelarsi dagli errori grossolani, sempre possibili. Infatti una analisi approfondita della logica della ricerca scientifica, ma non solo, constata la mancanza di verità sicure ed assolute, ritrovando invece solo alcune certezze, spesso molto precarie e provvisorie. In questo contesto, la conoscenza scientifica si struttura costruendo una sua teoria, in accordo con il matematico e filosofo Federigo Enriques, e riconoscendo come la scienza dipenda dall’ambiente, secondo la lezione del matematico e fisico Erwin Schrödinger. Dopodiché ritornando al pensiero espresso dal titolo, in una postfazione a mo’ di commiato, le Tuscolane di Cicerone offrono l’occasione per una serena disamina dei limiti della esistenza umana

Amino acid content and nectar choice by forager honeybees (Apis mellifera L.)

Dual choice feeding tests were performed to determine a preference of forager honeybees for specific amino acids. Artificial nectar containing proline was preferred over those containing only sugars. Nectar containing alanine was preferred on the first day, but preference was no longer significant thereafter. On the contrary, a negative response was found for serine. When the bees were given the choice between two nectars enriched with different compounds, proline was preferred above both alanine and serine, and alanine above serine

Genetic relationships among local Vitis vinifera cultivars from Campania (Italy)

A total of 114 accessions putatively corresponding to 69 local grape cultivars from Campania (Southern Italy) were analysed with 8 microsatellite markers (VVS2, VVMD5, VVMD7, VVMD25, VVMD27, VVMD31, VrZAG62 and VrZAG79) in order to evaluate their genetic diversity and relationships. According to their unique genotype at SSR loci finally 56 varieties were found. Interesting cases of synonymy, i.e. Greco di Tufo and Asprinio, Palummina and Piedirosso, and homonymy were disclosed. Pairwise genetic distances were calculated between all cultivars. Clustering of cultivars did not reflect their current distribution and this suggests that grape cultivars of Campania might have been introduced from various and distinct geographic areas

HEBE, a novel positive regulator of senescence in Solanum lycopersicum

Leaf senescence and plant aging are traits of great interest for breeders. Senescing cells undergo important physiological and biochemical changes, while cellular structures such as chloroplasts are degraded with dramatic metabolic consequences for the whole plant. The possibility of prolonging the photosynthetic ability of leaves could positively impact the plant\u2019s life span with benefits for biomass production and metabolite accumulation; plants with these characteristics display a stay-green phenotype. A group of plant transcription factors known as NAC play a pivotal role in controlling senescence: here we describe the involvement of the tomato NAC transcription factor Solyc12g036480, which transcript is present in leaves and floral buds. Since its silencing delays leaf senescence and prevents plants from ageing, we renamed Solyc12g0364 H\u1e16B\u112, for the Greek goddess of youth. In this manuscript we describe how HEB downregulation negatively affects the progression of senescence, resulting in changes in transcription of senescence-promoting genes, as well as the activity of enzymes involved in chlorophyll degradation, thereby explaining the stay-green phenotype

Reinvestigation of the tautomerism of some substituted 2-hydroxypyridines

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Functional consequences of mutations in CDKL5, an X-linked gene involved in infantile spasms and mental retardation

Mutations in the X-linked cyclin-dependent kinase-like 5 (CDKL5) gene have been identified in patients with Rett syndrome, West syndrome, and X-linked infantile spasms sharing the common features of generally intractable early seizures and mental retardation. Disease-causing mutations are distributed in both the catalytic domain and in the large COOH terminus. In this report, we examine the functional consequences of some Rett mutations of CDKL5 together with some synthetically designed derivatives useful to underline the functional domains of the protein. The mutated CDKL5 derivatives have been subjected to in vitro kinase assays and analyzed for phosphorylation of the TEY (Thr-Glu-Tyr) motif within the activation loop, their subcellular localization, and the capacity of CDKL5 to interact with itself. Whereas wild-type CDKL5 autophosphorylates and mediates the phosphorylation of the methyl-CpG-binding protein 2 (MeCP2) in vitro, Rett-mutated proteins show both impaired and increased catalytic activity suggesting that a tight regulation of CDKL5 is required for correct brain functions. Furthermore, we show that CDKL5 can self-associate and mediate the phosphorylation of its own TEY (Thr-Glu-Tyr) motif. Eventually, we show that the COOH terminus regulates CDKL5 properties; in particular, it negatively influences the catalytic activity and is required for its proper sub-nuclear localization. We propose a model in which CDKL5 phosphorylation is required for its entrance into the nucleus whereas a portion of the COOH-terminal domain is responsible for a stable residency in this cellular compartment probably through protein-protein interactions

Non-lethal effects of N-acetylcysteine on xylella fastidiosa strain De Donno biofilm formation and detachment

This study investigated in-vitro the non-lethal eects of N-acetylcysteine (NAC) on Xylella fastidiosa subspecies pauca strain De Donno (Xf-DD) biofilm. This strain was isolated fromthe olive trees aected by the olive quick decline syndrome in southern Italy. Xf-DD was first exposed to non-lethal concentrations of NAC from 0.05 to 1000 M. Cell surface adhesion was dramatically reduced at 500 M NAC (47%), hence, this concentration was selected for investigating the eects of pre-, postand co-treatments on biofilm physiology and structural development, oxidative homeostasis, and biofilm detachment. Even though 500 MNAC reduced bacterial attachment to surfaces, compared to the control samples, it promoted Xf-DD biofilm formation by increasing: (i) biofilm biomass by up to 78% in the co-treatment, (ii) matrix polysaccharides production by up to 72% in the pre-treatment, and (iii) reactive oxygen species levels by 3.5-fold in the co-treatment. Xf-DD biofilm detachment without and with NAC was also investigated. The NAC treatment did not increase biofilm detachment, compared to the control samples. All these findings suggested that, at 500 M, NAC diversified the phenotypes in Xf-DD biofilm, promoting biofilm formation (hyper-biofilm-forming phenotype) and discouraging biofilm detachment (hyper-attachment phenotype), while increasing oxidative stress level in the biofilm

A simple and reliable methodology to detect egg white in art samples

A protocol for a simple and reliable dot-blot immunoassay was developed and optimized to test work of art samples for the presence of specific proteinaceus material (i.e. ovalbumin-based). The analytical protocol has been extensively set up with respect, among the other, to protein extraction conditions, to densitometric analysis and to the colorimetric reaction conditions. Feasibility evaluation demonstrated that a commercial scanner and a free image analysis software can be used for the data acquisition and elaboration, thus facilitating the application of the proposed protocol to commonly equipped laboratories and to laboratories of museums and conservation centres. The introduction of method of standard additions in the analysis of fresh and artificially aged laboratory-prepared samples, containing egg white and various pigments, allowed us to evaluate the matrix effect and the effect of sample aging and to generate threshold density values useful for the detection of ovalbumin in samples from ancient works of art. The efficacy of the developed dot-blot immunoassay was proved testing microsamples from 13th–16th century mural paintings of Saint Francesco Church in Lodi (Italy). Despite the aging, the altered conditions of conservation, the complex matrix, and the micro-size of samples, the presence of ovalbumin was detected in all those mural painting samples where mass-spectrometry-based proteomic analysis unambiguously detected ovalbumin peptides