17 research outputs found

    Opening of Ancillary Service Markets to Distributed Energy Resources: A Review

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    Electric power systems are moving toward more decentralized models, where energy generation is performed by small and distributed power plants, often from renewables. With the gradual phase out from fossil fuels, however, Distribution Energy Resources (DERs) are expected to take over in the provision of all regulation services required to operate the grid. To this purpose, the opening of national Ancillary Service Markets (ASMs) to DERs is considered an essential passage. In order to allow this transition to happen, current opportunities and barriers to market participation of DERs must be clearly identified. In this work, a comprehensive review is provided of the state-of-the-art of research on DER integration into ASMs. The topic at hand is analyzed from different perspectives. First, the current situation and main trends regarding the reformation processes of national ASMs are analyzed to get a clear picture of the evolutions expected and adjustment required in the future, according to the scientific community. Then, the focus is moved to the strategies to be adopted by aggregators for the effective control and coordination of DERs, exploring the challenges posed by the uncertainties affecting the problem. Coordination schemes between transmission and distribution system operators, and the implications on the grid infrastructure operation and planning, are also investigated. Finally, the review deepens the control capabilities required for DER technologies to perform the needed control actions

    Quantitative evaluation of erythropoietic activity in dysmyelopoietic syndromes.

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    Based on the morphological appearances of the bone marrow and peripheral blood, 43 patients with dysmyelopoietic syndromes were categorized into four types: refractory anaemia with excess of blasts, chronic myelomonocytic leukaemia, primary acquired sideroblastic anaemia and refractory anaemia with cellular marrow, without excess of blasts and/or ring sideroblasts. Ferrokinetics allowed three distinct groups of patients to be defined. All cases of refractory anaemia with excess of blasts and chronic myelomonocytic leukaemia were classified in the same group. They were characterized by relative marrow failure and had a high likelihood of developing acute leukaemia. At the other end of the spectrum, individuals with primary acquired sideroblastic anaemia had high erythropoietic activity which was largely ineffective. They had a benign clinical course without evidence of leukaemic transformation. In the middle group, in terms of erythropoietic activity, lay patients with refractory anaemia with cellular marrow and a few individuals with primary acquired sideroblastic anaemia. Their clinical course and risk of developing acute leukaemia were intermediate between the other two groups. These findings indicate that separate entities may exist within the spectrum of dysmyelopoietic syndromes. In clinical practice, they may be recognized by morphological studies and other simple laboratory means

    Dietary and circulating polyunsaturated fatty acids in Cystic Fibrosis : are they related to clinical outcomes?

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    Objective: To assess the relationship between dietary intakes, plasma phospholipid (PL) fatty acid profile and clin. parameters in children with cystic fibrosis (CF) in comparison to healthy controls. Patients and methods: A cross-sectional survey including 37 patients with CF (ages 8.0 +- 2.9 yrs) and a ref. group of 68 healthy children (ages 8.0 +- 0.7 yrs) was carried out by means of a food-frequency questionnaire. At enrolment, all subjects underwent blood sampling for plasma PL fatty acids (FA). In CF patients, pulmonary function tests (forced expiratory vol. in 1 s and forced vital capacity), anthropometric measurements and the Shwachman score were also detd. Results: In CF patients, mean z score for wt. and height (-0.35 +- 1.16 and -0.28 +- 0.99) were lower than controls (0.83 +- 1.73 and 0.55 +- 1.11, resp.). Patients with CF showed higher energy intakes (110 +- 43 kcal/d) compared with controls (75 +- 22 kcal/d; P < 0.0001), with higher intake of total (satd. and monounsatd.) fats and lower intake of polyunsatd. FA (3.9 +- 1.0% of total macronutrient intake vs 4.3 +- 1.2%, P= 0.05). In CF patients, plasma and PL levels of linoleic and docosahexaenoic acids were lower, whereas those of arachidonic acid were similar compared with controls. The Shwachman score showed significant pos. assocns. with plasma PL levels of arachidonic acid and total n-6 long-chain FA (r= 0.32, P= 0.05, and r= 0.35, P= 0.03, resp.). Conclusions: The data give suggestions that fat intake and CF-assocd. biomechanisms are bound in a vicious circle, concurring to create the clin. and biochem. picture of CF. The quantity and quality of fat supplementation in CF need careful attention to balance the fat supply with polyunsatd. FA

    Lack of efficacy of Lactobacillus GG in reducing pulmonary exacerbations and hospital admissions in children with cystic fibrosis: A randomised placebo controlled trial

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    Background: Intestinal dysbiosis has been described in Cystic Fibrosis (CF) and probiotics have been proposed to restore microbial composition. Aim of the study was to investigate the effects of Lactobacillus rhamnosus GG (LGG) on clinical outcomes in children with cystic fibrosis (CF). Methods: A multicentre, randomised double-blind, clinical trial was conducted in children with CF. After 6months of baseline assessment, enrolled children (2 to 16years of age) received Lactobacillus GG (6\uc3\u97109CFU/day) or placebo for 12months. Primary outcomes were proportion of subjects with at least one pulmonary exacerbation and hospitalisation over 12months. Secondary endpoints were total number of exacerbations and hospitalisations, pulmonary function, and nutritional status. Results: Ninety-five patients were enrolled (51/95 female; median age of 103. \uc2\ub1. 50. months). In a multivariate GEE logistic analysis, the odds of experiencing at least one exacerbation was not significantly different between the two groups, also after adjusting for the presence of different microbial organisms and for the number of pulmonary exacerbations within 6. months before randomisation (OR 0.83; 95% CI 0.38 to 1.82, p = 0.643). Similarly, LGG supplementation did not significantly affect the odds of hospitalisations (OR 1.67; 95% CI 0.75 to 3.72, p = 0.211). No significant difference was found for body mass index and FEV1. Conclusions: LGG supplementation had no effect on respiratory and nutritional outcomes in this large study population of children with CF under stringent randomised clinical trial conditions. Whether earlier interventions, larger doses, or different strains of probiotics may be effective is unknown

    SARS-CoV-2 infection in cystic fibrosis: A multicentre prospective study with a control group, Italy, February-July 2020

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    Objective To describe the symptoms and clinical course of SARS-CoV-2 infection in patients with cystic fibrosis (CF). Methods We carried out a prospective multicentre cohort study based on 32 CF centres and 6597 patients. Centres were contacted to collect baseline and follow-up data of patients who reported symptoms suggestive of COVID-19 or who had contact with a positive/suspected case between the end of February and July 2020. Symptoms and clinical course of the infection were compared between patients who tested positive by molecular testing (cases) and those who tested negative (controls). Results Thirty patients were reported from the centres, 16 of them tested positive and 14 tested negative. No differences in symptoms and outcome of the disease were observed between groups. Fever, cough, asthenia and dyspnea were the most frequently reported symptoms. Eight cases (50%) were hospitalized but none required ICU admission. Two adults with a history of lung transplant required non-invasive ventilation, none required ICU admission and all patients fully recovered without short-term sequelae. Conclusions The course of SARS-CoV-2 in our patients was relatively favorable. However, COVID-19 should not be considered a mild disease in CF patients, particularly for those with severely impaired respiratory function and organ transplant

    Long-term outcome of vesicoureteral reflux associated chronic renal failure in children : data from the ItalKid project

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    PURPOSE: The nephropathy associated with vesicoureteral reflux (VUR) is one of the leading causes of chronic renal failure (CRF) in children. We describe the clinical course of the disease based on information available in the ItalKid Project database, and analyze the predictive value of baseline renal function, age at VUR diagnosis and urinary protein excretion in relation to the risk of progressive renal failure. MATERIALS AND METHODS: As of December 31, 2001 the registry included a total of 343 patients (261 males) with a diagnosis of primary VUR, which was the leading single cause of CRF, accounting for 25.4% of all patients with CRF. RESULTS: The estimated risk of end stage renal disease (ESRD) by age 20 years was 56%. The patients with a creatinine clearance (Ccr) of less than 40 ml per minute at baseline had an estimated 4-fold greater risk of ESRD developing in comparison with those whose Ccr was 40 to 75 ml per minute. No significant difference in probability of disease progression to ESRD was found between subjects diagnosed with VUR at age 6 months or less and those diagnosed later (older than 6 months). Furthermore, children with normal urinary protein excretion (a urinary protein [uPr]/urinary creatinine [uCr] ratio of less than 0.2 in 36 patients) and low grade proteinuria (uPr/uCr 0.2 to 0.8 in 34 patients) at baseline showed a significantly slower decrease in mean Ccr than those with moderate proteinuria (uPr/uCr greater than 0.8 in 34 patients). Hypertension and/or antihypertensive treatment (including antiprogressive drugs) were reported in 29.1% of patients. CONCLUSIONS: The results of the present study define the long-term risk of ESRD in a large population of children with CRF and VUR, and provide some critical information for identifying the prognosis
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