520 research outputs found

    Water confined in nanopores: spontaneous formation of microcavities

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    Molecular Dynamics simulations of water confined in nanometer sized, hydrophobic channels show that water forms localized cavities for pore diameter ~ 2.0 nm. The cavities present non-spherical shape and lay preferentially adjacent to the confining wall inducing a peculiar form to the liquid exposed surface. The regime of localized cavitation appears to be correlated with the formation of a vapor layer, as predicted by the Lum-Chandler-Weeks theory, implying partial filling of the pore

    Olive oils protected by the EU geographical indications: creation and distribution of the value-adding within supply chains

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    The world olive oil market is characterized by a growing price competition on the supply side. Economy of scales and low production costs from both traditional and more recent producing Countries determine an increasing pressure on European Union (EU) olive farmers that suffer lower revenues. Product differentiation, driven by higher quality and consumer expectations, is one of the most powerful competitive strategies that EU farmers may adopt to face this challenge. Geographical indications established by the EU (PDO and PGI) can be successful marketing levers to ensure olive oil differentiation based on high quality standards and geographical origin of production. These EU quality certification schemes were designed to respond to consumer demand, to ensure intellectual property protection for the most qualifying products, and to provide farmers with a fair share of the added value. There is a wide literature about the PDOs’ economic and social impacts, but only few studies analyze their benefits and costs along the supply chain. By investigating the added value generation process within an Italian PDO olive-oil supply chain (“Terra di Bari” PDO), this work aims to evaluate the effectiveness of PDO certification schemes in improving farm’s profitability. The study was performed directly interviewing a sample of the most representative farmers, manufacturers and stakeholders of the PDO olive oil supply chain localized in the Province of Bari (Puglia, Italy).olive oil, protected designation of origin, supply chain, value-chain., Agricultural and Food Policy,

    The International Olive Oil Trade A network analysis

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    Aim of this paper is to test weather or not the Network Analysis (NA) could possibly help to grasp Country level competitiveness in the International Trade Network (ITN) of a specific commodity. We focus over the positions that each Country occupies within the net of international trade exchanges assuming this could lead to competitive advantage. Starting from Ronald Burt's structural holes theory, we move forward analyzing the whole network evolution in the last years. We apply NA to the world network of valued exchange relationships of virgin olive oils building a 12 years time series of weighted directed networks (WDN)

    La trasmissione del prezzo nella filiera dell’uva da tavola: il caso del bacino di produzione del Sud-Est barese

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    Fresh food markets are affected by asymmetric price transmission along the value chain, from retail to producers and vice versa. The following paper explores the price generation mechanisms in Fresh table grape TG local market in S-E Bari (Southern Italy) to disclose asymmetric price transmission in one of the largest markets for TG worldwide using the Fuzzy Cognitive Maps (FCM) method. The FCM is an innovative analytical tool that helps digging expert and locally based market knowledge on price generation dynamics. Results showed as traders and farmers are both affected by ex-ogenous or endogenous shocks. Nonetheless, the distribution of the effects is unevenly distributed between these two agents

    Fungal communities living in the wood of different cultivars of young Vitis vinifera plants

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    The fungal communities associated with fi ve Vitis vinifera cultivars grown in Switzerland (‘Humagne’, ‘Chasselas’, ‘Arvine’, ‘Gamaret’ and ‘Gamay’) were examined. Of the 703 fungal isolates obtained in pure culture, 66 operational taxonomic units (OTUs) were defi ned. The results show that: the great majority of the fungi isolated in this study were ascomycetes, with a high proportion of Sordariomycetes (mainly Hypocreales, Sordariales and Diaporthales); different fungal OTUs were associated with different cultivars; graft and rootstock contributed equally to the fungal community composition; Esca- or Petri-related species occurred sporadically in the different cultivars, with some of them occupying specifi c tissues or parts of the plant (e.g.: Botryosphaeriaceous species, Phaeomoniella chlamydospora and Phomopsis viticola); almost 25% of OTUs occurred in different plant parts in most cultivars, which suggests an easy spread outwards from the infected material (graft or rootstock), which might be explained by the fungal propagules being transported through the xylem vessels

    Gene silencing of endothelial von Willebrand Factor attenuates angiotensin II-induced endothelin-1 expression in porcine aortic endothelial cells.

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    Expression of endothelin (ET)-1 is increased in endothelial cells exposed to angiotensin II (Ang II), leading to endothelial dysfunction and cardiovascular disorders. Since von Willebrand Factor (vWF) blockade improves endothelial function in coronary patients, we hypothesized that targeting endothelial vWF with short interference RNA (siRNA) prevents Ang II-induced ET-1 upregulation. Nearly 65 ± 2% silencing of vWF in porcine aortic endothelial cells (PAOECs) was achieved with vWF-specific siRNA without affecting cell viability and growth. While showing ET-1 similar to wild type cells at rest, vWF-silenced cells did not present ET-1 upregulation during exposure to Ang II (100 nM/24 h), preserving levels of endothelial nitric oxide synthase activity similar to wild type. vWF silencing prevented AngII-induced increase in nicotinamide adenine dinucleotide phosphate (NADPH) oxidase (NOX) activity and superoxide anion (O2-) levels, known triggers of ET-1 expression. Moreover, no increase in O2- or ET-1 levels was found in silenced cells treated with AngII or NOX-agonist phorbol ester (PMA 5 nM/48 h). Finally, vWF was required for overexpression of NOX4 and NOX2 in response to AngII and PMA. In conclusion, endothelial vWF knockdown prevented Ang II-induced ET-1 upregulation through attenuation of NOX-mediated O2- production. Our findings reveal a new role of vWF in preventing of Ang II-induced endothelial dysfunction

    Non random distribution of genomic features in breakpoint regions involved in chronic myeloid leukemia cases with variant t(9;22) or additional chromosomal rearrangements

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    <p>Abstract</p> <p>Background</p> <p>The t(9;22)(q34;q11), generating the Philadelphia (Ph) chromosome, is found in more than 90% of patients with chronic myeloid leukemia (CML). As a result of the translocation, the 3' portion of the <it>ABL1 </it>oncogene is transposed from 9q34 to the 5' portion of the <it>BCR </it>gene on chromosome 22 to form the <it>BCR</it>/<it>ABL1 </it>fusion gene. At diagnosis, in 5-10% of CML patients the Ph chromosome is derived from variant translocations other than the standard t(9;22).</p> <p>Results</p> <p>We report a molecular cytogenetic study of 452 consecutive CML patients at diagnosis, that revealed 50 cases identifying three main subgroups: i) cases with variant chromosomal rearrangements other than the classic t(9;22)(q34;q11) (9.5%); ii) cases with cryptic insertions of <it>ABL1 </it>into <it>BCR</it>, or vice versa (1.3%); iii) cases bearing additional chromosomal rearrangements concomitant to the t(9;22) (1.1%). For each cytogenetic group, the mechanism at the basis of the rearrangement is discussed.</p> <p>All breakpoints on other chromosomes involved in variant t(9;22) and in additional rearrangements have been characterized for the first time by Fluorescence In Situ Hybridization (FISH) experiments and bioinformatic analyses. This study revealed a high content of <it>Alu </it>repeats, genes density, GC frequency, and miRNAs in the great majority of the analyzed breakpoints.</p> <p>Conclusions</p> <p>Taken together with literature data about CML with variant t(9;22), our findings identified several new cytogenetic breakpoints as hotspots for recombination, demonstrating that the involvement of chromosomes other than 9 and 22 is not a random event but could depend on specific genomic features. The presence of several genes and/or miRNAs at the identified breakpoints suggests their potential involvement in the CML pathogenesis.</p

    Cardiovascular Response to Intraneural Right Vagus Nerve Stimulation in Adult Minipig.

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    Objective: This study explored intraneural stimulation of the right thoracic vagus nerve (VN) in sexually mature male minipigs to modulate safe heart rate and blood pressure response. Material and methods: We employed an intraneural electrode designed for the VN of pigs to perform VN stimulation (VNS). This was delivered using different numbers of contacts on the electrode and different stimulation parameters (amplitude, frequency, and pulse width), identifying the most suitable stimulation configuration. All the parameter ranges had been selected from a computational cardiovascular system model. Results: Clinically relevant responses were observed when stimulating with low current intensities and relatively low frequencies delivered with a single contact. Selecting a biphasic, charge-balanced square wave for VNS with a current amplitude of 500 ΌA, frequency of 10 Hz, and pulse width of 200 Όs, we obtained heart rate reduction of 7.67 ± 5.19 beats per minute, systolic pressure reduction of 5.75 ± 2.59 mmHg, and diastolic pressure reduction of 3.39 ± 1.44 mmHg. Conclusion: Heart rate modulation was obtained without inducing any observable adverse effects, underlining the high selectivity of the intraneural approach

    Late plasma exosome microRNA-21-5p depicts magnitude of reverse ventricular remodeling after early surgical repair of primary mitral valve regurgitation

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    Introduction: Primary mitral valve regurgitation (MR) results from degeneration of mitral valve apparatus. Mechanisms leading to incomplete postoperative left ventricular (LV) reverse remodeling (Rev–Rem) despite timely and successful surgical mitral valve repair (MVR) remain unknown. Plasma exosomes (pEXOs) are smallest nanovesicles exerting early postoperative cardioprotection. We hypothesized that late plasma exosomal microRNAs (miRs) contribute to Rev–Rem during the late postoperative period. Methods: Primary MR patients (n = 19; age, 45–71 years) underwent cardiac magnetic resonance imaging and blood sampling before (T0) and 6 months after (T1) MVR. The postoperative LV Rev–Rem was assessed in terms of a decrease in LV end-diastolic volume and patients were stratified into high (HiR-REM) and low (LoR-REM) LV Rev–Rem subgroups. Isolated pEXOs were quantified by nanoparticle tracking analysis. Exosomal microRNA (miR)-1, –21–5p, –133a, and –208a levels were measured by RT-qPCR. Anti-hypertrophic effects of pEXOs were tested in HL-1 cardiomyocytes cultured with angiotensin II (AngII, 1 ÎŒM for 48 h). Results: Surgery zeroed out volume regurgitation in all patients. Although preoperative pEXOs were similar in both groups, pEXO levels increased after MVR in HiR-REM patients (+0.75-fold, p = 0.016), who showed lower cardiac mass index (–11%, p = 0.032). Postoperative exosomal miR-21-5p values of HiR-REM patients were higher than other groups (p &lt; 0.05). In vitro, T1-pEXOs isolated from LoR-REM patients boosted the AngII-induced cardiomyocyte hypertrophy, but not postoperative exosomes of HiR-REM. This adaptive effect was counteracted by miR-21-5p inhibition. Summary/Conclusion: High levels of miR-21-5p-enriched pEXOs during the late postoperative period depict higher LV Rev–Rem after MVR. miR-21-5p-enriched pEXOs may be helpful to predict and to treat incomplete LV Rev–Rem after successful early surgical MVR
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