62 research outputs found
Clinical application of magnets in orthodontics and biological implications: a review
Over the last decade magnets have been used in orthodontic and dentofacial orthopaedics and attempts have been made to evaluate the biological implications of magnets and magnetic fields during clinical application. This review aims to indicate the advantages and disadvantages of magnets in orthodontics and dentofacial orthopaedics over traditional techniques, and update related clinical experiences. The treatment of impacted teeth and Class II malocclusions by means of magnetic force is favoured and the correction of Class III and open bite malocclusions involving the use of magnets also appears promising. The advantages of magnets over traditional force delivery systems are: frictionless mechanics, when the magnets are in attractive configuration; predictable force levels, no force decay over time and less patient co-operation. However, the size of the magnets can increase the bulk of the appliance and three-dimensional control is limited when the magnets are in a repulsive configuration. In addition magnets used in vivo require a coating to prevent corrosion and the possible side effects of corrosive product
Smoker's paradox in ST-elevation myocardial infarction: Role of inflammation and platelets.
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Serum uric acid may modulate the inflammatory response after primary percutaneous coronary intervention in patients with ST-elevation myocardial infarction
Prevalence and long-term outcomes of patients with coronary artery ectasia presenting with acute myocardial infarction
Coronary artery ectasia (CAE) is described in 5% of patients undergoing coronary angiography. Previous studies have shown controversial results regarding the prognostic impact of CAE. The prevalence and prognostic value of CAE in patients with acute myocardial infarction (AMI) remain unknown. In 4788 patients presenting with AMI referred for coronary angiography the presence of CAE (defined as dilation of a coronary segment with a diameter >= 1.5 times of the adjacent normal segment) was confirmed in 174 (3.6%) patients (age 62 + 12 years; 81% male), and was present in the culprit vessel in 79.9%. Multivessel CAE was frequent (67%). CAE patients were more frequently male, had high thrombus burden and were treated more often with thrombectomy and less often was stent implantation. Markis I was the most frequent angiographic phenotype (43%). During a median follow-up of 4 years (1-7), 1243 patients (26%) experienced a major adverse cardiovascular event (MACE): 282 (6%) died from a cardiac cause, 358 (8%) had a myocardial infarction, 945 (20%) underwent coronary revascularization and 58 (1%) presented with a stroke. Patients with CAE showed higher rates of MACE as compared to those without CAE (36.8% versus 25.6%; p <0.001). On multivariable analysis, CAE was associated with MACE (HR 1.597; 95% CI 1.238-2.060; p <0.001) after adjusting for risk factors, type of AMI and number of narrowed coronary arteries. In conclusion, the prevalence of CAE in patients presenting with AMI is relatively low but was independently associated with an increased risk of MACE at follow-up. (c) 2021 The Author(s). Published by Elsevier Inc. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/) (Am J Cardiol 2021;156:9-15)Cardiolog
Unsupervised system to classify SO2 pollutant concentrations in Salamanca, Mexico
Salamanca is cataloged as one of the most polluted cities in Mexico. In order to observe the behavior and clarify the influence of wind parameters on the Sulphur Dioxide (SO2) concentrations a Self-Organizing Maps (SOM) Neural Network have been implemented at three monitoring locations for the period from January 1 to December 31, 2006. The maximum and minimum daily values of SO2 concentrations measured during the year of 2006 were correlated with the wind parameters of the same period. The main advantages of the SOM Neural Network is that it allows to integrate data from different sensors and provide readily interpretation results. Especially, it is powerful mapping and classification tool, which others information in an easier way and facilitates the task of establishing an order of priority between the distinguished groups of concentrations depending on their need for further research or remediation actions in subsequent management steps. For each monitoring location, SOM classifications were evaluated with respect to pollution levels established by Health Authorities. The classification system can help to establish a better air quality monitoring methodology that is essential for assessing the effectiveness of imposed pollution controls, strategies, and facilitate the pollutants reduction
Time Course of Ischemic and Bleeding Burden in Elderly Patients With Acute Coronary Syndromes Randomized to Low-Dose Prasugrel or Clopidogrel
Background Elderly patients have high ischemic and bleeding rates after acute coronary syndrome; however, the occurrence of these complications over time has never been studied. This study sought to characterize average daily ischemic rates ( ADIRs ) and average daily bleeding rates ( ADBRs ) over 1\ua0year in patients aged >74\ua0years with acute coronary syndrome undergoing percutaneous coronary intervention who were randomized in the Elderly ACS 2 trial, comparing low-dose prasugrel (5\ua0mg daily) with clopidogrel (75\ua0mg daily). Methods and Results ADIRs and ADBRs were calculated as the total number of events, including recurrent events, divided by the number of patient-days of follow-up and assessed within different clinical phases: acute (0-3\ua0days), subacute (4-30\ua0days), and late (31-365\ua0days). Generalized estimating equations were used to test the least squares mean differences for the pairwise comparisons of ADIRs and ADBRs and the pairwise comparison of clopidogrel versus prasugrel effects. Globally, ADIRs were 2.6 times (95% CI, 2.4-2.9) higher than ADBRs . ADIRs were significantly higher in the clopidogrel arm than in the low-dose prasugrel arm in the subacute phase ( Padj<0.001) without a difference in ADBRs ( Padj=0.35). In the late phase, ADIRs remained significantly higher with clopidogrel ( Padj<0.001), whereas ADBRs were significantly higher with low-dose prasugrel ( Padj<0.001). Conclusions Ischemic burden was greater than bleeding burden in all clinical phases of 1-year follow-up of elderly patients with acute coronary syndrome treated with percutaneous coronary intervention. Low-dose prasugrel reduced ischemic events in the subacute and chronic phases compared with clopidogrel, whereas bleeding burden was lower with clopidogrel in the late phase. Clinical Trial Registration URL : http://www.clinicaltrials.gov . Unique identifier: NCT 01777503
Processi di estrazione a basso impatto ambientale di biopolimeri da biomasse batteriche
In questo lavoro di tesi sono state condotte prove di estrazione e recupero di poliidrossialcanoati (PHA) da biomasse batteriche fotosintetiche (Rhodovulum sulfidophilum) utilizzando solventi non clorurati quali cicloesanone, liquidi ionici e Deep Euthetic Solvents (DESs) in alternativa ai processi di estrazione tradizionali a base di cloroformio. Sono state ottimizzate le condizioni di estrazione, precipitazione e purificazione dei biopolimeri in termini di temperatura e tempo di attacco, rapporto solvente/biomassa e scelta del non solvente per lo stadio di precipitazione in vista del successivo recupero e riciclo dei solventi impiegati.
I biopolimeri estratti sono stati caratterizzati mediante analisi calorimetrica differenziale a scansione (DSC), analisi termo-gravimetrica (TGA), spettroscopia infrarossa (FTIR) e spettroscopia di risonanza magnetica nucleare (H-NMR e C-NMR) al fine di valutarne la stabilità termica, la purezza, la distribuzione dei pesi molecolari e il contenuto di valerato presente nel biopolimero. I risultati delle analisi sono stati confrontati con quelli delle analisi condotte su PHA commerciali quali poliidrossibutirrato (PHB) e poliidrossibutirrato-co-idrossivalerato (PHB-HV).
I migliori risultati sono stati raggiunti operando a 125°C per 20 min con cicloesanone nella fase di attacco, seguita da filtrazione e precipitazione dei PHA mediante aggiunta di etanolo. In tali condizioni si sono ottenute rese di estrazione pressoché totali e i PHA ottenuti sono risultati PHB-HV di elevata purezza con 4% di valerato, aventi stabilità termica, cristallinità , distribuzione dei pesi molecolari del tutto simili a quelli del PHB-HV commerciale, usato come riferimento.
I liquidi ionici e i DES selezionati si sono comportati come non solventi dei PHA e in grado, nei rapporti solventi/biomassa investigati, di dissolvere solo in parte la membrana cellulare batterica portando così a ottenere PHA di bassa purezza (50-55%) che necessitano di ulteriori trattamenti di purificazione. Tale indagine preliminare su tali solventi necessità pertanto di ulteriori prove sperimentali per selezionare i liquidi ionici e/o DES più performanti e le condizioni operative ottimali di estrazione che verranno svolte in Tesi future
Novel Dental Restorative Solutions for Natural Teeth and Implants
: The long-term survival of restorations in the oral cavity has always been one of the most significant challenges in modern dental practice [...]
I dati metereologici per applicazioni energetiche e ambientali
Many energetic and environmental evaluations need appropriate meteorological data, as input to analysis and prevision softwares.
In Italy there aren't adeguate meteorological data because, in many cases, they are incomplete, incorrect and also very expensive for a long-term analysis (that needs multi-year data sets).
A possible solution to this problem is the use of a Typical Meteorological Year (TRY), generated for specific applications. Nowadays the TRYs have been created, using statistical criteria, just for the analysis of solar energy systems and for predicting the thermal performance of buildings, applying it also to the study of photovoltaic plants (PV), though not specifically created for this type of application.
The present research has defined the methodology for the creation of TRYs for different applications. In particular TRYs for environmental and wind plant analysis have been created. This is the innovative aspect of this research, never explored before. In additions, the methodology of the generation for the PV TRYs has been improved.
The results are very good and the TRYs generated for these applications are adeguate to characterize the climatic condition of the place over a long period and can be used for energetic and environmental studies
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