Search results for "Dynamic"

Bivariate nonlinear prediction to quantify the strength of complex dynamical interactions in short-term cardiovascular variability.

2005

A nonlinear prediction method for investigating the dynamic interdependence between short length time series is presented. The method is a generalization to bivariate prediction of the univariate approach based on nearest neighbor local linear approximation. Given the input and output series x and y, the relationship between a pattern of samples of x and a synchronous sample of y was approximated with a linear polynomial whose coefficients were estimated from an equation system including the nearest neighbor patterns in x and the corresponding samples in y. To avoid overfitting and waste of data, the training and testing stages of the prediction were designed through a specific out-of-sampl…

General Relativistic Hydrodynamics and Magnetohydrodynamics: Hyperbolic Systems in Relativistic Astrophysics

2008

Bollettino di Matematica pura e applicata

2020

The paper emphasizes some the advances of knowledge in mathematics problems ad new applications. The Bollettino is open to the contribution of Italian or foreign researchers.

Blockchain Governance : A Dynamic View

2021

The governance of blockchain systems is unique due to its decentralized nature and automatically enforced rules and mechanisms. Moreover, blockchain governance is crucial in achieving success and sustainability. With this study, we aim to advance the theory of blockchain governance and support practitioners by defining blockchain governance from a holistic viewpoint and identifying its building blocks. As a result of a systematic literature review of 75 recent articles focusing on blockchain governance, we propose a dynamic model that deepens the researchers’ and practitioners’ understanding of blockchain governance. The conceptual model can serve as a reference framework and structured fou…

m.quadriceps statisku slodzi pavadošās hemodinamiskās reakcijas augšstilba maģistrālo artēriju gultnēs

2013

m.quadriceps statisku slodzi pavadošās hemodinamiskās reakcijas augšstilba maģistrālo artēriju gultnēs Pētījums veltīts perifēro artēriju un pretestības asinsvadu tonusa regulācijas īpatnību izpētei, reģionālai muskuļu asinsvadu gultnei iekļaujoties dažāda rakstura hemodinamiskās reakcijās. Promocijas darba pirmajā etapā tika veikti tālākā pētījumā izmantojamo metožu teorētiskā pamatojuma un praktiskās realizācijas pilnveidojumi: fotopletizmogrāfijas metodei – audu tilpuma pulsa un atsevišķas artērijas pulsa reģistrācijas metožu informativitātes salīdzinājums, artēriju ultrasonogrāfijas metodei – oriģinālas programmatūras izstrāde un aprobācija artērijas morfometrisko un asins plūsmas param…

Stable bioenergetic status despite substantial changes in blood flow and tissue oxygenation in a rat tumour.

1994

Experiments on s.c. rat tumours (DS sarcoma) were performed to determine whether chronic or acute changes in tumour perfusion necessarily lead to changes in tissue oxygenation and bioenergetic status since, as a rule, blood flow is thought to be the ultimate determinant of the tumour bioenergetic status. Based on this study, there is clear experimental evidence that growth-related or acute (following i.v. administration of tumour necrosis factor alpha) decreases in tumour blood flow are accompanied by parallel alterations in tissue oxygenation. In contrast, tumour energy status remains stable as long as flow values do not fall below 0.4-0.5 ml g-1 min-1, and provided that glucose as the mai…

Acute changes of systemic parameters in tumour-bearing rats, and of tumour glucose, lactate, and ATP levels upon local hyperthermia and/or hyperglyca…

1991

Arterial blood pressure and relevant parameters of the arterial blood (O2 and CO2 tensions, pH, haematocrit, serum electrolytes and osmolality) were determined in tumour-bearing rats upon local hyperthermia (HT) and/or hyperglycaemia (HG). Tumour heating was performed in a saline bath (44 degrees C) for 120 min; hyperglycaemia was induced by i.v. infusion of 40% glucose solution for 150 min [blood glucose levels: 35-40 mM during heating; total amount of glucose: 1.19 g/100 g body wt.; infusion rates: 0.31 ml (100 g body wt.)-1 min-1 for 2 min, 0.02 ml (100 g body wt.)-1 min-1 for 88 min, and 0.01 ml (100 g body wt.)-1 min-1 for 60 min]. Immediately after treatment, glucose, lactate and ATP …

The Impact of Amino Acids on Postprandial Glucose and Insulin Kinetics in Humans

2020

Different amino acids (AAs) may exert distinct effects on postprandial glucose and insulin concentrations. A quantitative comparison of the effects of AAs on glucose and insulin kinetics in humans is currently lacking. PubMed was queried to identify intervention studies reporting glucose and insulin concentrations after acute ingestion and/or intravenous infusion of AAs in healthy adults and those living with obesity and/or type 2 diabetes (T2DM). The systematic literature search identified 55 studies that examined the effects of l-leucine, l-isoleucine, l-alanine, l-glutamine, l-arginine, l-lysine, glycine, l-proline, l-phenylalanine, l-glutamate, branched-chain AAs (i.e., l-leucine, l-iso…

Effects of Strength Training and Reduced Training on Functional Performance and Metabolic Health Indicators in Middle-Aged Men

2007

Changes in muscular fitness and metabolic health indicators were examined in 22 men (57.9 +/- 6.6 years, BMI 24.5 +/- 2.6 kg/m (2)) and 21 control men (58.2 +/- 6.1 years, BMI 25.4 +/- 2.8 kg/m (2)) during two consecutive 21-week periods: 1) whole body progressive strength training (ST: twice a week), and 2) continued reduced training (CRT: 3 ST sessions/2 weeks, n = 17 + 17). After the 21-week ST period, maximal strength of leg extensors increased in the ST group by 19.6 +/- 7.6 % vs. 2.8 +/- 4.4 % (p < 0.001) and also 10-m walking time and 10-step stair-climbing time shortened by - 17.2 +/- 7.6 % vs. 4.1 +/- 3.9 % (p < 0.01) and by - 8.2 +/- 6.8 % vs. - 3.0 +/- 6.8 % (p < 0.05) compared t…

The sodium-glucose co-transporter 2 inhibitor empagliflozin improves diabetes-induced vascular dysfunction in the streptozotocin diabetes rat model b…

2014

Objective In diabetes, vascular dysfunction is characterized by impaired endothelial function due to increased oxidative stress. Empagliflozin, as a selective sodium-glucose co-transporter 2 inhibitor (SGLT2i), offers a novel approach for the treatment of type 2 diabetes by enhancing urinary glucose excretion. The aim of the present study was to test whether treatment with empagliflozin improves endothelial dysfunction in type I diabetic rats via reduction of glucotoxicity and associated vascular oxidative stress. Methods Type I diabetes in Wistar rats was induced by an intravenous injection of streptozotocin (60 mg/kg). One week after injection empagliflozin (10 and 30 mg/kg/d) was adminis…