•Geopolymer/graphene nanoplatelets composites show an electro-mechanical behaviour.•The value of the charge coefficient d33 is equal to 11.99 pC/N.•Graphene increases stiffness and ultimate strength ...of nanocomposites up to 0.5%wt.•Graphene clusters are observed at 1%wt.
In this work, authors report, for the first time, the evidence of an electro-mechanical behavior in geopolymer/graphene nanoplatelets (GNPs) composites, with the value of the charge coefficient d33, when 1%wt of GNPs is used, equal to 11.99 pC/N. The mechanical characterization of the nanocomposites is provided by using an innovative single test based on the combination of Brazilian disk test and Digital Image Correlation. The greatest increments in Young Modulus (E) and ultimate tensile strength (σT), with values of 17.44 ± 0.67 GPa and 6.26 ± 0.05 GPa respectively, were measured when 0.5%wt of GNPs was used.
Full text
Available for:
GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
While many questions remain unanswered in this challenging arena, the emerging status of biomarkers of inflammation provides an excellent illustration of how application of basic and clinical science ...of inflammation can lead to advances in clinical care. Yet we need to do better. We need to improve the number needed to treat. We should strive for further refinements in risk prediction to individualize interventions. Imaging and genetic biomarkers will likely find their place in clinical practice alongside traditional risk factors and biomarkers of inflammation in the years to come. We must aim to assure that individuals targeted for statin therapy do not lessen their adherence to a healthy lifestyle, believing that they enjoy pharmacological protection from unhealthy behaviours. At the other extreme, we need to counsel carefully certain patients to avoid creating a cohort of ‘cardiac neurotics’ with above median high-sensitivity C-reactive protein readings. We need to understand more about the mechanisms and clinical significance of unwanted actions of statins, including dysglycaemia. We need to devise measures to optimize lifestyle change at both a medical and societal level. For our individual patients, implementation of sustained lifestyle change has proved very challenging in practice, given the multiplicity of behaviours that require vigilance. The clinical use of biomarkers of inflammation may provide the practitioner with a tool to help gauge residual risk, and chart a course for its optimal management.
We concisely review clinical, autopsy, experimental and molecular data of 2019 coronavirus disease (COVID-19). Angiotensin-converting enzyme 2 disruption and thromboinflammatory microangiopathy ...emerge as distinctive features. Briefly, entry of the virus into microvessels can profoundly disrupt the local renin-angiotensin system, cause endothelial injury, activate the complement cascade and induce powerful thromboinflammatory reactions, involving, in particular, von Willebrand factor, that, if widespread, may lead to microvascular plugging, ischemia and, ultimately, organ failure. We believe the current COVID-19 data consolidate a widely unrecognised paradigm of potentially fatal thromboinflammatory microvascular disease.
•SARS-CoV-2 entry into microvessels can disrupt the local renin-angiotensin-system.•Complement and von Willebrand factor overexpression occur in COVID-19.•COVID-19 patients show widespread thromboinflammatory microvascular disease.•COVID-19 provides an important paradigm of potentially fatal microangiopathy.
Full text
Available for:
GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
To prospectively compare changes in myocardial blood flow (MBF) and myocardial flow reserve (MFR) in multivessel coronary artery disease (MVCAD) patients undergoing incomplete revascularization (IR) ...versus complete revascularization (CR) by coronary artery bypass grafting (CABG).
Seven male patients (age 68 ± 9 years) with MVCAD underwent myocardial perfusion PET/CT with 13Nammonia before and at least 4 months after CABG. Segmental resting and stress MBF as well as MFR were measured. Resting and during stress left ventricle ejection fraction (LVEF) were also calculated.
Three patients (43%) underwent CR and four (57%) IR. Among 119 myocardial segments, 101 (85%) were revascularized, and 18 (15%) were not. After CABG, stress MBF (mL/min/gr) and MFR are significantly increased in all myocardial segments, with a greater increase in the revascularized segments (p = 0.013). In both groups, LVEF significantly decreased during stress at baseline PET (p = 0.04), but not after CABG.
Stress MBF and MFR significantly improve after CABG in both revascularized and not directly revascularized myocardial segments. IR strategy may be considered in patients with high surgical risk for CR.
Full text
Available for:
EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
...a consensus document on the definition, classification, and management of patients with angina and normal coronary arteries would be very useful. Furthermore, in a recent study we found that ...spinal cord stimulation was associated with a notable improvement of symptoms and quality of life in about 50% of a small group of patients with syndrome X refractory to other forms of treatment, in the absence of major complications. ...this approach should be considered in patients with angina refractory to multi-drug treatment. 20 Stepwise approach In patients with angina and normal coronary arteries, the response to treatment is rather unpredictable.
Aims In patients recovering from acute coronary syndromes (ACS) the role of oral anticoagulation (and its intensity) in addition to aspirin remains controversial. We conducted a specific ...meta-analysis of randomized trials comparing aspirin plus warfarin (A+W) with aspirin alone in such patients. Methods and results MEDLINE and Cochrane databases yielded 14 (of 148 potentially relevant) articles enrolling 25 307 patients. Follow-up ranged from 3 months to 5 years. Irrespective of International normalized ratio (INR), A+W did not significantly affect the risk of major adverse events (MAE: all cause death, non-fatal myocardial infarction, and non-fatal thrombo-embolic stroke) when compared with aspirin alone OR 0.96 (0.90–1.03), P=0.30, but increased the risk of major bleeds (MB): OR 1.77 (1.47–2.13), P<0.00001. However, in studies with INR of 2–3, A+W was associated with a significant reduction of MAE OR 0.73 (0.63–0.84), P<0.0001, number needed to treat to avoid one MAE=33, albeit at an increased risk of MB OR 2.32 (1.63–3.29), P<0.00001; number needed to harm by causing one MB=100. In both analyses, intracranial bleeding was not significantly increased by A+W when compared with aspirin alone. Conclusion For patients recovering from ACS, a combined strategy of A+W at INR values of 2–3 doubles the risk of MB, but is nonetheless superior to aspirin alone in preventing MAE. Whether this combined regimen is also superior to a ‘double’ anti-platelet strategy or to newer evolving treatments warrants further investigation.
Landfill leachate is a multicomponent aqueous matrix generated by the percolation of rainwater into the body of a landfill. Considering its content of natural and xenobiotic components, it must be ...considered as a waste, whose composition depends on type of waste, biodegradation processes, rainwater, composition and compaction of waste and their age; these factors influence the transport, absorption, toxicity, bioaccumulation of the contaminants. Leachates sampled from landfill and downhill piezometers, in periods characterized by different rainfall, were studied by ATR-FTIR and SEM-EDX techniques; analyses were carried out on dried and calcinated residues obtained at T = 383 and 923 K, respectively. The chemical-physical characterization of all the leachates was carried out by using the official methods of analysis, obtaining for many metals and some organic contaminants exceedance of the concentrations with respect to the limits established by the Italian Legislative Decree 152/2006. From potentiometric titrations carried out at T = 298.15 K in NaCl(aq) and applying the Polyprotic Like model, each leachate resulted to have a different composition in terms of COOH and OH groups and various acid-base properties. The interacting ability of leachates with metal cations (Cd2+, Zn2+, Cu2+) was studied by potentiometric and voltammetric (only for Pb2+) techniques in NaCl (NaNO3 for Pb2+) aqueous solutions, at I = 0.15 mol dm−3 and T = 298.15 K, obtaining diverse speciation models and complexes of very different stability. The leachates sequestering ability towards the metal cations was quantified at various pH values using the pL0.5 parameter, proving that each leachate has a different strength of interaction towards the metals, that tends to increase with the pH and confirming that they behave as carriers of contaminants through the soil and towards groundwater, with the consequent problems of contamination and/or environmental disaster and risks for the human health.
Display omitted
•Contaminant concentrations depend on the rainfall and are inversely proportional to the quantity of water infiltrating.•The SEM-EDX and ATR-FTIR analyses highlight the presence of organic and inorganic functional groups.•The most present organic functional groups are the carboxylic and phenolic groups.•For the same leachate, the acid-base properties determined by using the Polyprotic Like Model vary during the year.•The different leachates have clearly different acid-base and complexing properties.
Full text
Available for:
GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Aims Thrombectomy in patients with ST-elevation myocardial infarction (STEMI) undergoing percutaneous coronary intervention (PCI) is associated to better myocardial reperfusion. However, no single ...trial was adequately powered to asses the impact of thrombectomy on long-term clinical outcome and to identify patients at higher benefit. Thus, we sought to assess these issues in a collaborative individual patient-data pooled analysis of randomized studies (study acronym: ATTEMPT, number of registration: NCT00766740). Methods and results Individual data of 2686 patients enrolled in 11 trials entered the pooled analysis. Primary endpoint of the study was all-cause mortality. Major adverse cardiac events (MACE) were considered as the occurrence of all-cause death and/or target lesion/vessel revascularization and/or myocardial infarction (MI). Subgroups analysis was planned according to type of thrombectomy device (manual or non-manual), diabetic status, IIb/IIIa-inhibitor therapy, ischaemic time, infarct-related artery, pre-PCI TIMI flow. Clinical follow-up was available in 2674 (99.6%) patients at a median of 365 days. Kaplan–Meier analysis showed that allocation to thrombectomy was associated with significantly lower all-cause mortality (P = 0.049). Thrombectomy was also associated with significantly reduced MACE (P = 0.011) and death + MI rate during the follow-up (P = 0.015). Subgroups analysis showed that thrombectomy is associated to improved survival in patients treated with IIb/IIIa-inhibitors (P = 0.045) and that the survival benefit is confined to patients treated in manual thrombectomy trials (P = 0.011). Conclusion The present large pooled analysis of randomized trials suggests that thrombectomy (in particular manual thrombectomy) significantly improves the clinical outcome in patients with STEMI undergoing mechanical reperfusion and that its effect may be additional to that of IIb/IIIa-inhibitors.
PDF
