101,993 research outputs found
Breve storia dei refrattari
No full textRassegna della evoluzione storica dei refrattari per applicazioni metallurgich
Aggregation-Induced Emission in Electrochemiluminescence: Advances and Perspectives
No full textThe discovery of aggregation-induced electrochemiluminescence (AIECL) in 2017 opened new research paths in the quest for novel, more efficient emitters and platforms for biological and environmental sensing applications. The great abundance of fluorophores presenting aggregation-induced emission in aqueous media renders AIECL a potentially powerful tool for future diagnostics. In the short time following this discovery, many scientists have found the phenomenon interesting, with research findings contributing to advances in the comprehension of the processes involved and in attempts to design new sensing platforms. Herein, we explore these advances and reflect on the future directions to take for the development of sensing devices based on AIECL. Graphic abstract: [Figure not available: see fulltext.]
Inspiratory drive is related to dynamic pulmonary hyperinflation in COPD patients
No full textBackground: Baseline high neuromuscular drive is present in chronic obstructive pulmonary disease (COPD). In moderate-to-very severe COPD patients both static and/or dynamic pulmonary hyperinflation have been demonstrated at rest.
Aim: To assess the influence of dynamic hyperinflation (DH) on neuromuscular drive at rest.
Methods: We recruited prospectively 22 patients with severe-to-very severe COPD showing resting dynamic pulmonary hyperinflation, as assessed by the baseline reduction of inspiratory capacity (IC) (< 80% of predicted). IC, occlusion pressure (P01), maximal inspiratory pressure (MIP) and their ratio was measured at end-expiratory lung volume (EELV) before and after acute inhalation of 400 mcg of albuterol (MDI plus spacer). In these patients the bronchodilator response was assessed also as lung volume changes.
Results: Only in COPD patients with a marked increase in IC (> 12% of baseline and at least 200 ml) after bronchodilator, resting P01 showed a clinically significant decrease, despite the EELV diminution (p<0.001). MIP was augmented following EELV reduction and therefore P01/MIP ratio was markedly decreased (p<0.001). In contrast, no changes in these indices were found after bronchodilator in COPD patients with insignificant variations of IC. Breathing pattern parameters did not vary in both sub-groups after albuterol.
Conclusion: Following bronchodilator, significant P01 decrease, MIP increase and reduction of P01/MIP ratio were found only in COPD patients with marked IC increase and these changes were closely related. These findings suggest that bronchodilators by decreasing DH may control exertional and/or chronic dyspnea partly through a reduction of central neuromuscular drive
Metabolic and circulatory responses to an isokinetic protocol
No full textThe metabolic demand and the cardiorespiratory responses to isokinetic rehabilitation protocol have been studied in 11 females (F) and 11 males (M; age: 25-30 years). The exercise consisted in 3 series of 5 maximal concentric knee extensions/flexions at 180, 120, 90, 120, 180°/s, with a 40 s pause between each series (total duration about 15 min). The work (extensors plus flexors) was determined; V̇E and V̇O2 were measured on a breath-by-breath basis. HR was continuously recorded and arterial pressure (AP) was measured during each pause. It resulted that: i) the work at 180°/s was 1170±400 J (mean±SD) in F and 1670±350 J in M, then changing according to the angular velocities (mean increase at 90°/s: 18% in F and 34% in M); ii) V̇O2, V̇E and HR increased in an exponential-like fashion, reaching constant values after about 2.5-3.5 min of exercise. V̇O2 was 0.8±0.2 L/min and 1.3±0.3 L/min, V̇E 30±6 L/min and 45±15 L/min and HR 153±13 b/min and 145±15 b/min in F and M, respectively; iii) systolic AP increased of about 20 mmHg for the entire exercise, while diastolic pressure was unchanged. Even if the exercise was intermittent, metabolic and cardiocirculatory steady states were reached, which indicate that the maximal isokinetic protocol of this study is comparable to a dynamic exercise of medium-high intensity
Critical Aspects and Challenges in the Design of Small Molecules for Electrochemiluminescence (ECL) Application
No full textElectrochemiluminescence (ECL) has gained renewed interest due to the strong parallel development of luminophores in the field of organic light emitting diodes (OLEDs) with which this technique shares several aspects. In this perspective review we discuss the most relevant advances of the past 15 years in the study of organic and organometallic compounds as ECL emitters, by dividing them in three different classes: i) fluorescent emitters, ii) phosphorescent emitters and iii) Thermally Activated Delayed Fluorescence (TADF) emitters; then, water-soluble organic luminophores will be also discussed. We focus on how their design, their photo- and electrochemical properties and, in particular, the nature of the emitter, affect their efficiency in ECL. Regardless of the type of luminophore or the photoluminescence quantum yield (PLQY), the literature converges on the fact that the most determining aspect is the stability of the oxidized/reduced form of the emitter. Even if phosphorescent emitters can show outstanding efficiency, this often requires the absence of oxygen. In the case of TADFs, there is also a strong dependence of photoluminescence both in terms of PLQY and emission energy on the polarity of the media, so compounds, that appear promising in organic solvents, may be very inefficient in aqueous media.In this perspective review, the most relevant progresses obtained in the last 15 years in the study of organic and organometallic luminophores as ECL emitters were discussed. Examples of fluorescent and phosphorescent emitters, Thermally Activated Delayed Fluorescence (TADF) emitters and finally, water-soluble organic luminophore were reported. imag
Aliprandi (L. et G.) et Pomella (M.). — Le Grandi Alpi nella Cartografia dei secoli passati (1482-1865). Con gli itinerari dei valichi tra la Val d'Aosta, la Savoia e il Valese e considerazioni sulla zona del Gran Paradiso.
No full textVeyret Paul. Aliprandi (L. et G.) et Pomella (M.). — Le Grandi Alpi nella Cartografia dei secoli passati (1482-1865). Con gli itinerari dei valichi tra la Val d'Aosta, la Savoia e il Valese e considerazioni sulla zona del Gran Paradiso. . In: Revue de géographie alpine, tome 63, n°1, 1975. pp. 152-153
Aliprandi (L. et G.) et Pomella (M.). — Le Grandi Alpi nella Cartografia dei secoli passati (1482-1865). Con gli itinerari dei valichi tra la Val d'Aosta, la Savoia e il Valese e considerazioni sulla zona del Gran Paradiso.
No full textVeyret Paul. Aliprandi (L. et G.) et Pomella (M.). — Le Grandi Alpi nella Cartografia dei secoli passati (1482-1865). Con gli itinerari dei valichi tra la Val d'Aosta, la Savoia e il Valese e considerazioni sulla zona del Gran Paradiso. . In: Revue de géographie alpine, tome 63, n°1, 1975. pp. 152-153
Establishment of Zeta Potential in Clays as an Alternative Indication for Viscosity and Plasticity
No full textProceedings of the XV Conference on Silicate Industry and Silicate Scienc
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