28 research outputs found

    Renewable Electric Energy Integration: Quantifying the Value of Design of Markets for International Transmission Capacity

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    Integrating large quantities of supply-driven renewable electricity generation remains a political and operational challenge. One of the main obstacles in Europe to installing at least 200 GWs of power from variable renewable sources is how to deal with the insufficient network capacity and the congestion that will result from new flow patterns. We model the current methodology for controlling congestion at international borders and compare its results, under varying penetrations of wind power, with a model that simulates an integrated European network that utilises nodal/localised marginal pricing. The nodal pricing simulations illustrate that congestion - and price - patterns vary considerably between wind scenarios and within countries, and that a nodal price regime could make fuller use of existing EU network capacity, introducing substantial operational cost savings and reducing marginal power prices in the majority of European countries.Power market design, renewable power integration, congestion management, transmission economics

    Alzheimer's disease and gastrointestinal microbiota; impact of Helicobacter pylori infection involvement

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    Background: Alzheimer disease (AD) is a leading cause of global burden with great impact on societies. Although research is working intensively on promising therapy, the problem remains up-to-date. Among the various proposed hypotheses regarding causality and therapy, emerging evidence supports the hypothesis that gastrointestinal microbiota through the so-called 'gut-brain axis' interacts with immune system and brain and shape the balance between homeostasis and disease; the involvement of gastrointestinal microbiota in the pathophysiology of AD is less defined, even though the role of 'gut-brain axis' has been well verified for other neurodegenerative conditions.Methods: We performed a systematic review of PubMed/MEDLINE database from 1st^{st} January 1990 to 17th^{th} October 2018, to investigate the accessible literature regarding possible association between AD and gastrointestinal microbiota. Inclusion criteria were available full text in English language, original clinical papers implicating AD patients and any sort of gastrointestinal microbiota.Results: Through our query, an initial number of 241 papers has been identified. After removing duplicates and through an additional manual search, twenty-four papers met our inclusion criteria. The great majority of eligible publications supported a possible connection between AD and gastrointestinal microbiota. The most common investigated microorganism was Helicobacter pylori.Conclusion: Our own systematic review, showed a possible association between AD and gastrointestinal microbiota mainly including Helicobacter pylori, and thus further research is required for substantiation of causality as well as for the establishment of promising novel therapies

    Impact of nitric oxide's bidirectional role on glaucoma: focus on Helicobacter pylori-related nitrosative stress

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    Nitric oxide (NO), a small molecule generated ubiquitously, targets a plethora of tissues to regulate both physiological and pathophysiological functions. NO overproduction, stimulated by microenvironmental conditions, is the main component that dysregulates the tight balance between its beneficial and damaging roles in ocular homeostasis. Considering the protective functions of NO against glaucoma, its endogenous release facilitates aqueous humor drainage and regulates ocular blood flow, maintaining a normal intraocular pressure. NO overproduction generates free radicals, such as peroxynitrite, which induce a vicious circle of vascular disharmony and dysregulation, transient ischemia, nitrosative stress, neuronal degeneration, and permanent glaucomatic injury. Helicobacter pylori (Hp) is considered a burdening factor of glaucoma. NO overproduction and possible systematic dispersion in Hp infection (Hp-I) could suggest a potential pathophysiological bridge between these conditions. In this review, we aim to elucidate the role of NO in glaucoma with respect to Hp-I, with the aim to stimulate further studies

    Effect of add-on devices with projections on screening colonoscopy: a systematic review and meta-analysis

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    Background Add-on devices with projections, e.g., Endocuff, Endocuff Vision, EndoRings, and Wingcap, placed on the distal tip of the colonoscope promise to improve the detection of precancerous lesions. We performed a meta-analysis to evaluate the performance of these devices exclusively among individuals undergoing colonoscopy for screening purpose. Methods A computerized literature search was performed across MEDLINE and Cochrane Library databases for randomized controlled trials that compared standard colonoscopy (SC) to procedures using add-on devices. The primary outcome was adenoma detection rate (ADR), while secondary outcomes included polyp detection rate (PDR), advanced ADR (AADR), and sessile serrated lesion detection rate (SSLDR). The effect size on study outcomes was calculated using a random-effects model and presented as the risk ratio (RR) and 95% confidence interval (CI). Results Seven studies enrolling a total of 5785 patients were included. The use of add-on-devices with projections was associated with a higher ADR compared to SC: 45.9% vs. 41.1%; RR 1.18, 95%CI 1.02-1.37; P=0.03; & UIota;2=79%. Although PDR was higher in screening colonoscopies assisted by add-on devices as compared to SC, the difference failed to reach significance: 55.1% vs. 50.8%; RR 1.10, 95%CI 0.96-1.26; P=0.17; & UIota;2=75%. No difference was found between procedures assisted by add-on devices with projections and SC colonoscopies in terms of AADR (18.5% vs. 17.6%; RR 1.00, 95%CI 0.79-1.27; P=0.98; & UIota;2=56%) or SSLDR (6.8% vs. 5.8%; RR 1.17, 95%CI 0.95-1.44; P=0.15; I2=0%). Conclusion Colonoscopy assisted by add-on devices with projections achieves a better ADR compared to SC among individuals undergoing screening for bowel cancer

    Expression of integrin-linked kinase and its binding partners in chondrosarcoma: Association with prognostic significance

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    Integrin-linked kinase (ILK) and its binding partners alpha-parvin, beta-parvin, Mig-2 and Migfilin are important components of the cell-matrix adhesions implicated in cell motility, growth, survival and ultimately carcinogenesis. Herein, we investigated immunohistochemically the expression of these molecules in cartilaginous neoplasms and explored their involvement in chondrosarcoma pathobiology and behaviour. Our analyses revealed that ILK, alpha-parvin, beta-parvin and Mig-2 are expressed in the majority of chondrosarcomas but in a small proportion of enchondromas, implying that these proteins might have a role in the development and progression of chondrogenic neoplasms. moreover, our findings highlight the possibilities that ILK might serve as biological marker that could accurately predict a high-grade tumour and that Mig-2 may function as a promising prognostic indicator of high-risk patients. (C) 2008 Elsevier Ltd. All rights reserved
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