262 research outputs found

    Fluidized Bed Combustion of Liquid Bio-Fuels: Application of Integrated Diagnostics for Micro-Explosions Characterization

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    A novel integrated diagnostic technique has been developed for the analysis of the “regime with microexplosions” that may be established during the low-temperature (T < 800 °C) fluidized bed combustion of liquid fuels. It consists of the comparison among three analogue data series: (i) pressure signals measured in the freeboard and high-pass filtered, (ii) oxygen molar fractions measured by zirconia-based probes at two elevations in the bed and in the splash region, and (iii) video frames of the bed surface recorded and purposely worked out. The integrated technique has been applied to the combustion of biodiesel at minimum fluidization and has proven to be a valid tool to provide the fingerprints of the mechanism of the low-temperature fluidized combustion of liquid fuels. The time series generated from the measured data sets have been analyzed with the aid of the Hurst’s rescaled range analysis, the V-statistic, and the Lyapunov exponents’ evaluation. The issue of localizing micro-explosions throughout bed, bubbles, and splash zone has been tackled by the V-statistic analysis, which has proven that the location of micro-explosions is just at the bed surface when T = 650 °C and moves deeper and deeper into the bed when its temperature increased to about 800 °C. The values found for the largest Lyapunov exponent in the time series demonstrate that the investigated system is not only dynamic but also chaotic in its nature

    Identification of material properties and optimal design of magnetically shielded rooms

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    In this paper, we propose an optimal design procedure for magnetically shielded rooms. Focusing on multi-layer ferromagnetic structures, where inner layers operate at very low magnetic field, we propose an identification method of the magnetic material characteristic in the Rayleigh region. A numerical model to simulate the shielding efficiency of a multi-layer ferromagnetic structure is presented and experimentally tested on different geometries and layer configurations. The fixed point iterative method is adopted to handle the nonlinearity of the magnetic material. In conclusion, the optimization of the design parameters of a MSR is discussed, using the Vector Immune System algorithm to minimize the magnetic field inside the room and the cost of the structure. The results highlight that a linear magnetic characteristic for the material is sufficient to identify the suitable geometry of the shield, but the nonlinear model in the Rayleigh region is of fundamental importance to determine a realistic shielding factor

    Adjuvant benefit of a peptide-rich marine biology formula (LD-1227) in rheumatoid arthritis: a randomized, double-blind, controlled study

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    Introduction. There is a growing interest on non-chemical therapies among patients suffering from rheumatoid arthritis (RA), although safety, efficacy and properly designed studies are often lacking. Objective. The aim of the present investigation was to explore the clinical effectiveness of a marine nutraceutical, LD-1227, endowed by fine molecular biology studies, in the management of RA. Methods. The study design was a 12-week, randomized, double-blind study involving forty patients with stable longstanding RA who were randomized to receive either LD-1227 (n = 20) or Omega-3 (n = 20) on top of their established maintenance therapy. Results. At study recruitment and after 12 weeks of treatment, their Health Assessment Questionnaire (HAQ), erythrocyte sedimentation rate (ESR), visual analogue scale (VAS), and Disease Activity Score (DAS) 28, anxiety and depression analysis, C-reactive protein (CRP) levels, CXCL1, several pro-inflammatory interleukins levels and related gene expression, were compared between the two groups. Primary end point was the proportion of patients with response at weeks 12 as from the 20 % to 50% improvement criteria of the American College of Rheumatology (ACR20). At 12 weeks, ACR20 beneficial response was 81.0 % in LD-1227 group and 44 % in omega-3 group, (p&lt; 0.01). The superiority of LD-1227 appeared also when considering the ACR50 response at 12 weeks (62% in LD-1227 group as compared to 31 % in omega-3 group, p&lt; 0.01). The LD-1227-treated group displayed a significant improvement of VAS scale, HAQ score, morning stiffness and tender points (p &lt; 0.01 vs control and p &lt; 0.05 vs omega-3, respectively). From the biochemical viewpoint, patients in the LD-1227 group showed a lower level of CRP, IL-6, TNF-α, IL-1β, CXCL1, IFNγ, IL-15 and IP-10 and significant downregulation of related gene expressions. Unlike what observed in LD-1227 group, in the omega-3 group, CRP and DAS28 did not reach statistical difference. A substantial reduction of extra pain killer use was noted under LD-1227 treatment. Conclusion. One can conclude that LD-1227 may play a significant role on the management of RA and with a specrum and mechanisms of actions distinct from the canonical omega-3 while being devoid of any side effect or tolerability issues

    Studies on the potential antioxidant properties of Senecio stabianus Lacaita (Asteraceae) and its inhibitory activity against carbohydrate-hydrolysing enzymes

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    This study showed for the first time the antioxidant and hypoglycaemic properties of the methanol, n-hexane and ethyl acetate extracts from Senecio stabianus Lacaita, a plant that belongs to the Asteraceae family. The antioxidant activities were carried out using two different in vitro assays, namely 2,2-diphenyl-1-picrylhydrazyl (DPPH) test and 2,2\u2032-azinobis(3- ethylbenzthiazoline-6-sulphonate) (ABTS) test. The ethyl acetate extract showed the highest activity with inhibitory concentration 50% (IC 50) values of 35.5 and 32.7 \u3bcg mL -1 on DPPH test and ABTS test, respectively. This activity may be related to a good total phenol and flavonoid content. All extracts were also tested for their potential inhibitory activity of \u3b1-amylase and \u3b1-glucosidase digestive enzymes. The n-hexane extract exhibited the highest \u3b1-amylase inhibition with an IC 50 value of 0.21 mg mL -1. Through bioassay-guided fractionation processes seven fractions (A-G) were obtained and tested. Based on the phytochemical analysis, the activity of n-hexane extract may be related to the presence of monoterpenes and sesquiterpenes

    A randomized, controlled trial on the effectiveness of a proprietary marine lipo-peptide formula vs omega-3 on cytokines profile, anxiety, and pain symptoms in patients with fibromyalgia

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    Objective: The aim of the present study in an RCT manner (physicians and patients) a novel lipo-peptide marine compound, LD-1227, on physical-, emotional- and functional-related symptomatic complaints in fibromyalgia patients as well as inflammatory cytokines profile and gene expression while using omega-3 as a control group. Methods: The following questionnaire-based or clinical evaluation-based parameters were evaluated: widespread pain index [WPI] patient global impression of change, total tender points [TTP], fibromyalgia impact questionnaire, Beck depression inventory, fatigue severity ratings, cognitive symptom severity, symptom severity score [SSS] and weekly pain intensity ratings. Additional biochemical and gene expression analysis of cytokines (IL6, TNF-α, IL-1β, MCP-1, IL-8, IL-13, IL-1α, and GM-CSF) was performed as well. Data were analyzed with either a paired t-test or the Wilcoxon signed rank test depending on the parametric or non-parametric distribution. Results: Comparing the data from before and after treatment for Group B indicated a statistically significant reduction (p=0.05) in TTP, WPI score, and SSS score. These data suggest a positive effect of a 3-month treatment with the LD-1227 but not omega-3 treatment on Fibromyalgia pain and related anxiety/depressive symptoms. Inspections of HRV and Cytokines found a statistically significant improvement after LD1227 treatment. Unlike the group supplemented with omega-3, the treatment with LD-1227 brought about a decrease in WPI and weekly pain intensity symptoms for the majority of participants. The pre-and post-treatment data for Group B indicated a statistically significant reduction (p=0.05) in TPC, WPI, and SSS scores. No adverse events were reported. Conclusion: These results provide the first indications that the LD-1227 treatment has a statistically significant effect on the recognized fibromyalgia diagnosis metrics of WPI, TTP, and SSS as well on inflammatory markers and parasympathetic balance

    Improved procedural workflow for catheter ablation of paroxysmal AF with high-density mapping system and advanced technology: Rationale and study design of a multicenter international study

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    The antral region of pulmonary veins (PV)s seems to play a key role in a strategy aimed at preventing atrial fibrillation (AF) recurrence. Particularly, low-voltage activity in tissue such as the PV antra and residual potential within the antral scar likely represent vulnerabilities in antral lesion sets, and ablation of these targets seems to improve freedom from AF. The aim of this study is to validate a structured application of an approach that includes the complete abolition of any antral potential achieving electrical quiescence in antral regions.The improveD procEdural workfLow for cathETEr ablation of paroxysmal AF with high density mapping system and advanced technology (DELETE AF) study is a prospective, single-arm, international post-market cohort study designed to demonstrate a low rate of clinical atrial arrhythmias recurrence with an improved procedural workflow for catheter ablation of paroxysmal AF, using the most advanced point-by-point RF ablation technology in a multicenter setting. About 300 consecutive patients with standard indications for AF ablation will be enrolled in this study. Post-ablation, all patients will be monitored with ambulatory event monitoring, starting within 30 days post-ablation to proactively detect and manage any recurrences within the 90-day blanking period, as well as Holter monitoring at 3, 6, 9, and 12 months post-ablation. Healthcare resource utilization, clinical data, complications, patients' medical complaints related to the ablation procedure and patient's reported outcome measures will be prospectively traced and evaluated.The DELETE AF trial will provide additional knowledge on long-term outcome following a structured ablation workflow, with high density mapping, advanced algorithms and local impedance technology, in an international multicentric fashion. DELETE AF is registered at ClinicalTrials.gov (NCT05005143).© 2022 The Authors. Clinical Cardiology published by Wiley Periodicals LLC
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