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11.
Glazed pottery with “negative decoration” samples, dating back to the twelfth to thirteenth century ad and coming from three sites along the Adriatic coast, Siponto, Egnatia and Trani (Southern Italy) were characterized from physical–chemical, mineralogical and morphological points of view. Optical microscopy, scanning electron microscopy with energy dispersive X-ray spectroscopy, inductively coupled plasma-mass spectroscopy, X-ray diffraction and micro-Raman spectroscopy investigations were carried out on ceramic bodies, pigments and glazes of the fragments. We aimed to outline the technological features, define the nature of decorations and coatings—glazes and engobes—and look for clues to hypothesize provenance. Results obtained show clear differences in raw materials and production technology between the impressed ceramic of Islamic tradition and the incised one of Byzantine tradition. Regarding the latter, evidences of a non-local origin can be found in the compositional diversity of raw materials used for the ceramic bodies of fragments decorated with spiral and pseudo-kufic motifs, which stressed the use of clays so far not recorded in Apulia. At the same time, at least in the case of Siponto, the compositional similarity of both ceramic bodies and materials used under the glaze for impressed ceramic and painted polychrome ceramics (RMR and protomaiolica), more likely local production, could suggest that both were produced in the same workshops.  相似文献   
12.
This study presents a fully automated membrane segmentation technique for immunohistochemical tissue images with membrane staining, which is a critical task in computerized immunohistochemistry (IHC). Membrane segmentation is particularly tricky in immunohistochemical tissue images because the cellular membranes are visible only in the stained tracts of the cell, while the unstained tracts are not visible. Our automated method provides accurate segmentation of the cellular membranes in the stained tracts and reconstructs the approximate location of the unstained tracts using nuclear membranes as a spatial reference. Accurate cell-by-cell membrane segmentation allows per cell morphological analysis and quantification of the target membrane proteins that is fundamental in several medical applications such as cancer characterization and classification, personalized therapy design, and for any other applications requiring cell morphology characterization. Experimental results on real datasets from different anatomical locations demonstrate the wide applicability and high accuracy of our approach in the context of IHC analysis.  相似文献   
13.
Donatello Materassi 《Physica A》2009,388(18):3866-3878
The paper deals with the problem of reconstructing the internal link structure of a network of agents subject to mutual dependencies. We show that standard multivariate approaches based on a correlation analysis are not well suited to detect mutual influences and dependencies, especially in the presence of delayed or propagative relations and when the sampling rate is sufficiently high to capture them. In particular, we develop and apply a metric based on the coherence function to take into account these dynamical phenomena. The effectiveness of the proposed approach is illustrated through numerical examples and through the analysis of a real complex networked system, i.e. a set of 100 high volume stocks of the New York Stock Exchange, observed during March 2008 and sampled at high frequency.  相似文献   
14.
Tanacetum parthenium (feverfew) has traditionally been employed as a phytotherapeutic remedy in the treatment of migraine. In this study, a commercial T. parthenium water extract was investigated to explore its anti-inflammatory and neuromodulatory effects. Isolated mouse cortexes were exposed to a K+ 60 mM Krebs-Ringer buffer and treated with T. parthenium water extract. The prostaglandin E2 (PGE2) level, brain-derived neurotrophic factor (BDNF), interleukin-10 (IL-10), and IL-1β gene expression were evaluated in the cortex. The effects on dopamine (DA) release and dopamine transporter (DAT) gene expression were assayed in hypothalamic HypoE22 cells. A bioinformatics analysis was conducted to further investigate the mechanism of action. The extract was effective in reducing cortex PGE2 release and IL-1β gene expression. In the same experimental system, IL-10 and BDNF gene expressions increased, and in HypoE22 cells, the extract decreased the extracellular dopamine level and increased the DAT gene expression due to the direct interaction of parthenolide with the DAT. Overall, the present findings highlight the efficacy of T. parthenium water extract in controlling the inflammatory pathways that occur during cortical-spreading depression. Additionally, the inhibition of the hypothalamic DA release observed in this study further supports the role of dopaminergic pathways as key targets for novel pharmacological approaches in the management of migraine attacks.  相似文献   
15.
A hexagonal-BN target was ablated by high-fluence (6 and 12 J/cm2) KrF excimer laser pulses in low-pressure (5 Pa) N2 atmosphere, without any aid of ion bombardment and heating of the Si substrate. Investigations of the deposited films show that the cubic-BN phase was deposited. The film deposited at 6 J/cm2 appears to contain a higher cubic phase content with respect to the one deposited at 12 J/cm2.  相似文献   
16.
Some emission spectra of diatomic molecules were calculated by a semi-automatic programme package in order to infer the rotational and vibrational temperatures in Boltzmann distribution by comparing them with the corresponding experimental ones. The calculation procedure was applied in the case of CN radical and C2 molecule whose optical emission spectra were recorded during pulsed excimer laser ablation of a graphite target in low-pressure nitrogen environment. Computed similar or dissimilar values of rotational and vibrational temperatures let to verify the existence or not of local thermodynamic equilibrium and to hypothesise the temporal range necessary to establish it in such experiments.  相似文献   
17.
Osteoarthritis (OA) is a complex disease, source of pain and disability that affects millions of people worldwide. OA etiology is complex, multifactorial and joint-specific, with genetic, biological and biomechanical components. Recently, several studies have suggested a potential adjuvant role for natural extracts on OA progression, in terms of moderating chondrocyte inflammation and following cartilage injury, thus resulting in an overall improvement of joint pain. In this study, we first analyzed the phenylethanoid glycosides profile and the total amount of polyphenols present in a leaf aqueous extract of Verbascum thapsus L. We then investigated the anti-inflammatory and anti-osteoarthritic bioactive potential of the extract in murine monocyte/macrophage-like cells (RAW 264.7) and in human chondrocyte cells (HC), by gene expression analysis of specifics inflammatory cytokines, pro-inflammatory enzymes and metalloproteases. Six phenylethanoid glycosides were identified and the total phenolic content was 124.0 ± 0.7 mg gallic acid equivalent (GAE)/g of extract. The biological investigation showed that the extract is able to significantly decrease most of the cellular inflammatory markers, compared to both control cells and cells treated with Harpagophytum procumbens (Burch.) DC. ex Meisn, used as a positive control. Verbascum thapsus leaf aqueous extract has the potential to moderate the inflammatory response, representing an innovative possible approach for the inflammatory joint disease treatment.  相似文献   
18.
Natural dyes have been used extensively in the past for many purposes, such us to colour fibers and to produce inks, watercolours and paints, but their use declined rapidly after the discovery of synthetic colours. Nowadays we witness a renewed interest, as natural dyes are neither toxic nor polluting.  相似文献   
19.
Vitis vinifera (grape) contains various compounds with acknowledged phytochemical and pharmacological properties. Among the different parts of the plant, pomace is of particular interest as a winemaking industry by-product. A characterization of the water extract from grape pomace from Montepulciano d’Abruzzo variety (Villamagna doc) was conducted, and the bioactive phenolic compounds were quantified through HPLC-DAD-MS analysis. HypoE22, a hypothalamic cell line, was challenged with an oxidative stimulus and exposed to different concentrations (1 µg/mL−1 mg/mL) of the pomace extract for 24, 48, and 72 h. In the same conditions, cells were exposed to the sole catechin, in a concentration range (5–500 ng/mL) consistent with the catechin level in the extract. Cell proliferation was investigated by MTT assay, dopamine release through HPLC-EC method, PGE2 amount by an ELISA kit, and expressions of neurotrophin brain-derived neurotrophic factor (BDNF) and of cyclooxygenase-2 (COX-2) by RT-PCR. The extract reverted the cytotoxicity exerted by the oxidative stimulus at all the experimental times in a dose-dependent manner, whereas the catechin was able to revert the oxidative stress-induced depletion of dopamine 48 h and 72 h after the stimulus. The extract and the catechin were also effective in preventing the downregulation of BDNF and the concomitant upregulation of COX-2 gene expression. In accordance, PGE2 release was augmented by the oxidative stress conditions and reverted by the administration of the water extract from grace pomace and catechin, which were equally effective. These results suggest that the neuroprotection induced by the extract could be ascribed, albeit partially, to its catechin content.  相似文献   
20.
A new class of models based on hysteresis functions is developed to describe the operation of dynamic mode atomic force microscopy. Such models can account for dissipative phenomena affecting the interaction between the probe and the sample. The model analysis, which is developed using frequency domain techniques, provides a insights into experimentally observed behavior. Experimental data corroborates the models developed.  相似文献   
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