scholarly journals Influence of physical exercise on cardiovascular parameters in students with different types of blood flow autoregulation

2021 ◽  
pp. 138-145
Author(s):  
S. N. Melnik ◽  
L. A. Belaya

Objective: to assess cardiovascular parameters in medical students depending on the type of blood flow autoregulation during physical exercise.Material and methods. We examined 58 students whose average age was 19 ± 1.13 years. During the examination, we recorded electrocardiograms (ECG), registered the parameters of central hemodynamics and determined systolic and diastolic blood pressure and heart rate. We performed the comparison of the parameters of the cardiovascular system (CVS) in students with different types of blood flow autoregulation (BFA) (cardiac, cardiovascular and vascular) during physical exercise.Results. The study has identified the dynamics of electrocardiographic and rheographic parameters during physical exercise expressed in excessive activation of energy resources and strain of the CVS functioning in young men with the cardiac type of BFA, which provides adaptation to short-term effects of disturbing environmental factors. On the contrary, the vascular type of BFA is the most economical, and this type of CVS has a wide range of the function mobilization to long-term physical activity.Conclusion. The study has found statistically significant differences in the cardiovascular parameters in the students with different types of blood flow autoregulation during physical activity.

Polymers ◽  
2021 ◽  
Vol 13 (10) ◽  
pp. 1598
Author(s):  
Chih-Yu Chung ◽  
Yu-Ju Chen ◽  
Chia-Hui Kang ◽  
Hung-Yun Lin ◽  
Chih-Ching Huang ◽  
...  

Carbon quantum dots (CQDs) are emerging novel nanomaterials with a wide range of applications and high biocompatibility. However, there is a lack of in-depth research on whether CQDs can cause acute or long-term adverse reactions in aquatic organisms. In this study, two different types of CQDs prepared by ammonia citrate and spermidine, namely CQDAC and CQDSpd, were used to evaluate their biocompatibilities. In the fish embryo acute toxicity test (FET), the LD50 of CQDAC and CQDSpd was about 500 and 100 ppm. During the stage of eleutheroembryo, the LD50 decreased to 340 and 55 ppm, respectively. However, both CQDs were quickly eliminated from embryo and eleutheroembryo, indicating a lack of bioaccumulation. Long-term accumulation of CQDs was also performed in this study, and adult zebrafish showed no adverse effects in 12 weeks. In addition, there was no difference in the hatchability and deformity rates of offspring produced by adult zebrafish, regardless of whether they were fed CQDs or not. The results showed that both CQDAC and CQDSpd have low toxicity and bioaccumulation to zebrafish. Moreover, the toxicity assay developed in this study provides a comprehensive platform to assess the impacts of CQDs on aquatic organisms in the future.


2021 ◽  
Vol 141 (3) ◽  
pp. 527-533
Author(s):  
P. Moog ◽  
M. Dozan ◽  
J. Betzl ◽  
I. Sukhova ◽  
H. Kükrek ◽  
...  

Abstract Introduction Although the WALANT technique’s long-term safeness has been demonstrated in many studies, there are only few data investigating its short-term effects on tissue perfusion and oxygen levels. It was hypothesized that, temporarily, critical levels of tissue perfusion may occur. Methods Seventeen patients, who were scheduled for different procedures in WALANT technique, were injected with 5–7 ml of 1% Articain containing 1:200,000 epinephrine at the finger base. Capillary-venous oxygen saturation, hemoglobin volume in the capillaries, and relative blood flow in the fingertips were recorded once per second by white light spectrometry and laser Doppler flowmetry before, during and after injection for an average of 32 min. Results Clinically, no persistent tissue malperfusion was observed, and there were no postoperative complications. Capillary-venous oxygen saturation was reduced by ≥ 30% in seven patients. Critical levels of oxygen saturation were detected in four patients during 13 intervals, each lasting for 132.5 s on average. Oxygen saturation returned to noncritical values in all patients by the end of the observation period. Blood flow in the fingertips was reduced by more than 30% in nine patients, but no critical levels were observed, as with the hemoglobin. Three patients demonstrated a reactive increase in blood flow of more than 30% after injection. Conclusions Injection of tumescent local anesthesia containing epinephrine into finger base may temporarily cause a substantial reduction in blood flow and lead to critical levels of oxygen saturation in the fingertips. However, this was fully reversible within minutes and does not cause long-term complications.


Author(s):  
Vidhi Shah

Abstract: This research was conducted to gather data and understand the perception what the Indian population holds when it comes to investing in cryptocurrency. To do so, a survey was designed using the UTAUT model and was circulated by the means of google forms. A wide range of parameters were considered to avail the maximum possible accuracy for the data collected. Parameters like, the ease of investing crypto, short term and long term benefits, monetary benefits, social benefits were considered. All of these parameters were supposed to be answered on a scale of 5. After collecting all the data, the results were analyzed and evaluated using which the hypothesis made were proved. Keywords: Cryptocurrency, UTAUT, performance expectancy, effort expectancy, perceived monetary benefits, perceived safety, social influence, adoption intension.


1996 ◽  
Vol 39 (2) ◽  
Author(s):  
G. Asch ◽  
K. Wylegalla ◽  
M. Hellweg ◽  
D. Seidl ◽  
H. Rademacher

During the Proyecto de Investigaciòn Sismològica de la Cordillera Occidental (PISCO '94) in the Atacama desert of Northern Chile, a continuously recording broadband seismic station was installed to the NW of the currently active volcano, Lascar. For the month of April, 1994, an additional network of three, short period, three-component stations was deployed around the volcano to help discriminate its seismic signals from other local seismicity. During the deployment, the volcanic activity at Lascar appeared to be limited mainly to the emission of steam and SO2. Tremor from Lascar is a random, «rapid-fire» series of events with a wide range of amplitudes and a quasi-fractal structure. The tremor is generated by an ensemble of independent elementary sources clustered in the volcanic edifice. In the short-term, the excitation of the sources fluctuates strongly, while the long-term power spectrum is very stationary.


1978 ◽  
Vol 54 (1) ◽  
pp. 69-74 ◽  
Author(s):  
R. Wootton ◽  
J. Reeve ◽  
E. Spellacy ◽  
M. Tellez-Yudilevich

1. Blood flow to the skeleton was measured by the 18F clearance method of Wootton, Reeve & Veall (1976) in 24 patients with untreated Paget's disease. In every patient but one, resting skeletal blood flow was increased. There was a significant positive correlation between skeletal blood flow and serum alkaline phosphatase and between skeletal blood flow and urinary total hydroxyproline excretion. 2. Fourteen patients were re-studied after they had received short-term (7 days or less) or long-term (7 weeks or more) calcitonin. Skeletal blood flow, alkaline phosphatase and urinary hydroxyproline excretion fell towards normal in every case. There was some evidence from the short-term studies that calcitonin produced a more rapid fall in skeletal blood flow than in alkaline phosphatase. 3. Glomerular filtration rate appeared to increase transiently in response to calcitonin.


2008 ◽  
Vol 80 (2) ◽  
pp. 301-309 ◽  
Author(s):  
Pâmela Billig Mello ◽  
Fernando Benetti ◽  
Martín Cammarota ◽  
Iván Izquierdo

Here we study the effect of acute and chronic physical exercise in a treadmill and of daily stress (because forced exercise involves a degree of stress) during 2 or 8 weeks on different types of memory in male Wistar rats. The memory tests employed were: habituation in an open field, object recognition and spatial learning in the Morris water maze. Daily foot-shock stress enhanced habituation learning after 2 but not after 8 weeks; it hindered both short- (STM) and long-term memory (LTM) of the recognition task at 2 weeks but only STM after 8 weeks and had no effect on spatial learning after either 2 or 8 weeks. Acute but not chronic exercise also enhanced habituation in the open field and hindered STM and LTM in the recognition task. Chronic exercise enhanced one important measure of spatial learning (latency to escape) but not others. Our findings indicate that some care must be taken when interpreting effects of forced exercise on brain parameters since at least part of them may be due to the stress inherent to the training procedure.


2020 ◽  
pp. 336-362
Author(s):  
Peter Ferdinand

This chapter focuses on democracies, democratization, and authoritarian regimes. It first considers the two main approaches to analysing the global rise of democracy over the last thirty years: first, long-term trends of modernization, and more specifically economic development, that create preconditions for democracy and opportunities for democratic entrepreneurs; and second, the sequences of more short-term events and actions of key actors at moments of national crisis that have precipitated a democratic transition — also known as ‘transitology’. The chapter proceeds by discussing the different types of democracy and the strategies used to measure democracy. It also reviews the more recent literature on authoritarian systems and why they persist. Finally, it examines the challenges that confront democracy in the face of authoritarian revival.


2019 ◽  
Vol 219 (3) ◽  
pp. 2148-2164
Author(s):  
A M Lombardi

SUMMARY The operational earthquake forecasting (OEF) is a procedure aimed at informing communities on how seismic hazard changes with time. This can help them live with seismicity and mitigate risk of destructive earthquakes. A successful short-term prediction scheme is not yet produced, but the search for it should not be abandoned. This requires more research on seismogenetic processes and, specifically, inclusion of any information about earthquakes in models, to improve forecast of future events, at any spatio-temporal-magnitude scale. The short- and long-term forecast perspectives of earthquake occurrence followed, up to now, separate paths, involving different data and peculiar models. But actually they are not so different and have common features, being parts of the same physical process. Research on earthquake predictability can help to search for a common path in different forecast perspectives. This study aims to improve the modelling of long-term features of seismicity inside the epidemic type aftershock sequence (ETAS) model, largely used for short-term forecast and OEF procedures. Specifically, a more comprehensive estimation of background seismicity rate inside the ETAS model is attempted, by merging different types of data (seismological instrumental, historical, geological), such that information on faults and on long-term seismicity integrates instrumental data, on which the ETAS models are generally set up. The main finding is that long-term historical seismicity and geological fault data improve the pseudo-prospective forecasts of independent seismicity. The study is divided in three parts. The first consists in models formulation and parameter estimation on recent seismicity of Italy. Specifically, two versions of ETAS model are compared: a ‘standard’, previously published, formulation, only based on instrumental seismicity, and a new version, integrating different types of data for background seismicity estimation. Secondly, a pseudo-prospective test is performed on independent seismicity, both to test the reliability of formulated models and to compare them, in order to identify the best version. Finally, a prospective forecast is made, to point out differences and similarities in predicting future seismicity between two models. This study must be considered in the context of its limitations; anyway, it proves, beyond argument, the usefulness of a more sophisticated estimation of background rate, inside short-term modelling of earthquakes.


Sports ◽  
2019 ◽  
Vol 7 (1) ◽  
pp. 10 ◽  
Author(s):  
Sascha Leisterer ◽  
Darko Jekauc

Physical education (PE) can be the starting point for many students to be physically active throughout their lives. Positive emotional experiences in PE are discussed as beneficial for long-term physical activity, however, triggers of students’ emotions are still unclear. The purpose of this study is to explore, from a student’s perspective, emotions and their triggers, which occur in PE classes. N = 12 students (male: six, female: six, ø-age: 15.6 ± 1.2 years) have been interviewed using a focused semi-structured interview to identify their emotions in PE and to explore the situations in which they occurred. An inductive approach with elements of the Grounded Theory Method was implemented to analyze the data. Students reported a wide range of positive and negative emotions. Furthermore, four crucial triggers were identified: (I) Attractiveness of the task, (II) social belonging, (III) competence and (IV) autonomy. Parallels to existing theories, especially the Self-Determination Theory (SDT), will be discussed. These results can be used to improve teachers’ knowledge about students’ emotions in PE in order to build a basis for lifelong physical activity.


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