cyclic processes
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2022 ◽  
Vol 20 (8) ◽  
pp. 2892
Author(s):  
O. M. Drapkina ◽  
A. V. Kontsevaya ◽  
A. V. Budnevsky ◽  
E. S. Ovsyannikov ◽  
E. S. Drobysheva ◽  
...  

Cardiovascular disease remains the most relevant public health problem. Most cardiovascular diseases are associated with an atherosclerosis, the development of which is associated with inflammation and endothelial dysfunction. Melatonin is a neurohormone that is synthesized mainly in the pineal gland and plays a central role in the regulation of sleep and some other body cyclic processes. For a long time, melatonin was perceived as a substance that is effective in the treatment of circadian cycle impairments. At the same time, a large number of studies have accumulated recently that demonstrate a wider range of its biological effects, including anti-inflammatory, antioxidant, antihypertensive and, possibly, hypolipidemic. The review includes current data from experimental and clinical studies demonstrating the cardioprotective effects of melatonin in atherosclerosis, myocardial ischemia, and heart failure.


Author(s):  
Liudmyla Zhuchenko

The production of carbon products is largely resource- and energy-intensive. That is why increasing the efficiency of this production is an urgent scientific and practical task, especially in modern conditions of constant growth of energy costs. An effective way to solve this problem is to create a modern process control system, taking into account possible failures of system components. A method for the synthesis of a fault-tolerant control system for the cyclic formation of carbon products has been developed, which takes into account control errors that are caused by malfunctions of controllers under conditions of unknown disturbances. According to the cyclic nature of the technological process under consideration, a control method with iterative learning was used in the synthesis of the control system. This method considers cyclic processes based on a two-dimensional model (2D model). The proposed control algorithm ensures the convergence of the control process with the task both in time and in each work cycle in order to promote the required quality of control even in the event of unknown disturbances and errors in the performance of controllers. The synthesis of the control system is based on the solution of a system of linear matrix inequalities. Based on the combination of a control method with iterative learning and a control method that takes into account failures in controllers, a method of constructing a fault-tolerant control system for the cyclic formation of carbon products has been synthesized to ensure acceptable operation of the control object in abnormal conditions. The control system has been synthesized by solving a system of linear matrix inequalities with the MATLAB software. In the future, it is necessary to consider optimal settings of the proposed control system and examine its effectiveness in comparison with conventional fault-tolerant systems for non-cyclic processes.


Geosciences ◽  
2021 ◽  
Vol 11 (12) ◽  
pp. 504
Author(s):  
Luca Cocchi ◽  
Fabio Caratori Tontini ◽  
Filippo Muccini ◽  
Cornel E. J. de Ronde

Volcanism is the most widespread expression of cyclic processes of formation and/or destruction that shape the Earth’s surface. Calderas are morphological depressions resulting from the collapse of a magma chamber following large eruptions and are commonly found in subduction-related tectono-magmatic regimes, such as arc and back-arc settings. Some of the most impressive examples of seafloor hydrothermal venting occur within submarine calderas. Here, we show the results of magnetic investigations at two hydrothermally active submarine calderas, i.e., Palinuro Seamount in the Southern Tyrrhenian Sea, Italy, and Brothers volcano of the Kermadec arc, New Zealand. These volcanoes occur in different geodynamic settings but show similarities in the development of their hydrothermal systems, both of which are hosted within calderas. We present a new integrated model based on morphological, geological and magnetic data for the Palinuro caldera, and we compare this with the well-established model of Brothers caldera, highlighting the differences and common features in the geophysical expressions of both hydrothermal systems. For consistency with the results at Brothers volcano, we build a model of demagnetised areas associated with hydrothermal alteration derived from 3D inversion of magnetic data. Both these models for Brothers and Palinuro show that hydrothermal up-flow zones are strongly controlled by caldera structures which provide large-scale permeability pathways, favouring circulation of the hydrothermal fluids at depth.


2021 ◽  
Vol 31 (12) ◽  
pp. 123129
Author(s):  
J. Newman ◽  
M. Lucas ◽  
A. Stefanovska
Keyword(s):  

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Saeko Kita ◽  
Heidi Houston ◽  
Suguru Yabe ◽  
Sachiko Tanaka ◽  
Youichi Asano ◽  
...  

AbstractSlow slip phenomena deep in subduction zones reveal cyclic processes downdip of locked megathrusts. Here we analyze seismicity within a subducting oceanic slab, spanning ~50 major deep slow slip with tremor episodes over 17 years. Changes in rate, b-values, and stress orientations of in-slab seismicity are temporally associated with the episodes. Furthermore, although stress orientations in the slab below these slow slips may rotate slightly, in-slab orientations 20–50 km updip from there rotate farther, suggesting that previously-unrecognized transient slow slip occurs on the plate interface updip. We infer that fluid pressure propagates from slab to interface, promoting episodes of slow slip, which break mineral seals, allowing the pressure to propagate tens of km further updip along the interface where it promotes transient slow slips. The proposed methodology, based primarily on in-slab seismicity, may help monitor plate boundary conditions and slow slip phenomena, which can signal the beginning stages of megathrust earthquakes.


Cells ◽  
2021 ◽  
Vol 10 (10) ◽  
pp. 2661
Author(s):  
Paweł Kordowitzki ◽  
Roswitha Merle ◽  
Pascal-Kolja Hass ◽  
Johanna Plendl ◽  
Juliane Rieger ◽  
...  

Worldwide, dairy cows of the type of high-producing cattle (HPC) suffer from health and fertility problems at a young age and therefore lose productivity after an average of only three lactations. It is still contentious whether these problems are primarily due to genetics, management, feeding or other factors. Vascularization plays a fundamental role in the cyclic processes of reproductive organs, as well as in the regeneration of tissues. In a previous study, HPC were shown to have a greater ovarian corpus luteum vascularization compared to dual-purpose breeds. We hypothesize that this activated angiogenesis could likely lead to an early exhaustion of HPC′s regenerative capacity and thus to premature reproductive senescence. The objective of this study was to investigate if a HPC breed (Holstein-Friesian, HF) exhibits higher ovarian angiogenesis than a dual-purpose breed (Polish Red cow, PR) and if this is related to early ovarian aging and finally reproductive failure. For this purpose, we assessed the degree of vascularization by means of ovarian blood vessel characterization using light microscopy. As indicators for aging, we measured ovarian mitochondrial size and telomere length in peripheral leukocytes. We report in this study that in both breeds the distance between capillaries became smaller with increasing age and that the mean telomere length decreased with increasing age. The only difference between the two breeds was that PR developed larger capillaries than HF. Neither a relationship between telomere length, nor the morphology of the mitochondrial apparatus and nor angiogenesis in HF was proven. Although the data trends indicated that the proportion of shortened telomeres in HF was higher than in the PR, no significant difference between the two breeds was detected.


Nanomaterials ◽  
2021 ◽  
Vol 11 (10) ◽  
pp. 2476
Author(s):  
Brindha Ramasubramanian ◽  
M. V. Reddy ◽  
Karim Zaghib ◽  
Michel Armand ◽  
Seeram Ramakrishna

Metal-ion batteries are capable of delivering high energy density with a longer lifespan. However, they are subject to several issues limiting their utilization. One critical impediment is the budding and extension of solid protuberances on the anodic surface, which hinders the cell functionalities. These protuberances expand continuously during the cyclic processes, extending through the separator sheath and leading to electrical shorting. The progression of a protrusion relies on a number of in situ and ex situ factors that can be evaluated theoretically through modeling or via laboratory experimentation. However, it is essential to identify the dynamics and mechanism of protrusion outgrowth. This review article explores recent advances in alleviating metal dendrites in battery systems, specifically alkali metals. In detail, we address the challenges associated with battery breakdown, including the underlying mechanism of dendrite generation and swelling. We discuss the feasible solutions to mitigate the dendrites, as well as their pros and cons, highlighting future research directions. It is of great importance to analyze dendrite suppression within a pragmatic framework with synergy in order to discover a unique solution to ensure the viability of present (Li) and future-generation batteries (Na and K) for commercial use.


2021 ◽  
pp. 80-84
Author(s):  
S. L. Tsenteradze ◽  
M. G. Poluektov

The results of multicenter clinical trials show the broad potential of melatonin since discovery of this adaptogen to the present day. Melatonin is a neuropeptide that is synthesized mainly in the small brain gland, the pineal gland, and has a unique effect in humans and animals. Using melatonin, the pineal gland participates in the organization of circadian periodism and regulation of cyclic processes, acting as an intermediary between the pacemaker mechanism of the suprachiasmatic nuclei (SCN) and peripheral organs. The pineal gland and the SCN of the hypothalamus form part of the system of the so-called biological clock of the body, which plays a key role in the mechanisms of regulation of the biological clock via circadian rhythms and ageing. Initially, melatonin was only considered a hormone involved in the synchronization of the mechanisms of the circadian rhythm, but later it was found that, in addition to this hormonal function, it takes part in the regulation of the seasonal cycle in animals and humans.At present, melatonin drugs have shown high efficacy and safety in various sleep-wake disorders regardless of their genesis, disorganization of circadian rhythms, stress adjustment disorders, rapid change of time zones, shift work and in complex therapy of patients with cerebrovascular diseases.The article considers the multimodal capabilities of melatonin, including adaptogenic, biorhythmogenic, hypnotic, immunostimu-lating, antioxidant effects. The role of melatonin in the treatment of various central nervous system disorders, including neurodegenerative diseases, has been determined.The review emphasizes the wide-ranging effects of melatonin and offers great opportunities for measuring melatonin as a biomarker for early detection and follow-up of various diseases.


Author(s):  
Verma Dr. Amit Kumar

Vorticella stalk is the storehouse of two types of novel proteins, known with the names of spasmins and batonnets. On the basis of nature of proteins and the arrangements of amino acid residues of these proteins, the repeated consequential cyclic processes of contraction dynamics worked by neutralizing the negatively charged amino acid residues as per the laws obeyed by Heber-Weiss, Nernst and Fenton reactions. H+-integrated physiological performances in combination with pCa (partial pressure of calcium ion concentrations) and DNFB (2,4 – dinitrofluorobenzene/Sanger’s reagent) concentration gradients at the range of 1mM to 5mM represented velocity inclination in acidic medium which were more actively pronounced if it was compared with alkaline medium where permeabilized stalk exaggerated potential biochemical-shift-perturbation if it was in respect of non-permeabilized live specimens in both artificial as well as in natural medium in different experimental trials under controlled electro-physiological instrumental setup conditions. On the basis of these experimental designs it was confirmed that spasmins and batonnets are two different types of novel proteins with multitudes of potential applications in the favour of biomedical engineering devices formulation, then their construction at the nano-scale where H+-integrated pCa dependent electrophysiological nature of recommended proteins were found more ROS (reactive oxygen species) resistant if there was the introduction of DNFB in fixed concentrations than in the acto-myosin as well as tubulin-dynein systems being exclusively controlled under post-translational biochemical reactions catalysed in the light of software based modern bioinformatics’ tools and techniques. In live as well as permeabilized specimens, different types of biochemical reaction kinetics of amino acid residues were performed at different rates among the sequentially determined spasmins and batonnets like novel proteins where molecular orientations and motive-force generation in measurable parameters per millisecond confirmed the electrophysiological significance of Vorticella stalks’ on the basis of colligative nature of novel proteins of saccular compartments of spasmoneme, the well explained active contractile organelle of the stalk in relation with other resembling proteins found in Protein Data Bank (PDB) as centrins, calmodulins and others significantly pronounce their life saving and medicinal properties. This present statement/study was aimed to know the biochemical behaviour of spasmins and batonnets like novel proteins in the light of electrochemical behavior of the Vorticella stalk under some selective chemical stress conditions, that’s why this research helped us to know the ROS resistance properties of novel protein polymers found in stalk. On the basis of which reference proteins as described in this paper can be used as a diagnostic tools in pharmaceutical industries in the favour of molecular medicines and drugs’ designing.


Author(s):  
W. Muschik

AbstractNon-equilibrium processes in Schottky systems generate by projection onto the equilibrium subspace reversible accompanying processes for which the non-equilibrium variables are functions of the equilibrium ones. The embedding theorem which guarantees the compatibility of the accompanying processes with the non-equilibrium entropy is proved. The non-equilibrium entropy is defined as a state function on the non-equilibrium state space containing the contact temperature as a non-equilibrium variable. If the entropy production does not depend on the internal energy, the contact temperature changes into the thermostatic temperature also in non-equilibrium, a fact which allows to use temperature as a primitive concept in non-equilibrium. The dissipation inequality is revisited, and an efficiency of generalized cyclic processes beyond the Carnot process is achieved.


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