Heart remodeling occurs as a compensation mechanism for the massive loss of tissue during initial heart failure and the consequent inflammation process. During heart remodeling fibroblasts differentiate to myofibroblasts activate their secretion functions and produce elevated amounts, of extracellular matrix (ECM) proteins, mostly collagen, that form scar tissue and alter the normal degradation of ECM. Scar formation does replace the damaged tissue structurally; however, it impedes the normal contractive function of cardiomyocytes (CMs) and results in longlasting effects after heart failure. Besides CMs and cardiac fibroblasts, endothelial cells (ECs) and circulating endothelial progenitor cells (cEPCs) contribute to heart repair. This review summarizes the current knowledge of EC-CM crosstalk in cardiac fibrosis (CF), the role of cEPCs in heart regeneration and the contribution of Endothelial-mesenchymal transition (EndoMT)., Barbara Šalingová, Zdenko Červenák, Andriana Adamičková, Nikola Chromanicová, Simona Valášková, Andrea Gažová, Ján Kyselovič., and Obsahuje bibliografii
The Three Gorges Reservoir region suffers from severe soil erosion that leads to serious soil degradation and eutrophication. Interrill erosion models are commonly used in developing soil erosion control measures. Laboratory simulation experiments were conducted to investigate the relationship between interrill erosion rate and three commonly hydraulic parameters (flow velocity V, shear stress τ and stream power W). The slope gradients ranged from 17.6% to 36.4%, and the rainfall intensities varied from 0.6 to 2.54 mm·min–1. The results showed that surface runoff volume and soil loss rates varied greatly with the change of slope and rainfall intensity. Surface runoff accounted for 67.2–85.4% of the precipitation on average. Soil loss rates increased with increases of rainfall intensity and slope gradient, Regression analysis showed that interrill erosion rate could be calculated by a linear function of V and W. Predictions based on V (R2 = 0.843, ME = 0.843) and W (R2 = 0.862, ME = 0.862) were powerful. τ (R2 = 0.721, ME = 0.721) did not seem to be a good predictor for interrill erosion rates. Five ordinarily interrill erosion models were analyzed, the accuracy of the models in predicting soil loss rate was: Model 3 (ME = 0.977) > Model 4 (ME = 0.966) > Model 5 (ME = 0.963) > Model 2 (ME = 0.923) > Model 1 (ME = 0.852). The interrill erodibility used in the model 3 (WEPP) was calculated as 0.332×106 kg·s·m–4. The results can improve the precision of interrill erosion estimation on purple soil slopes in the Three Gorges Reservoir area.
As stated by Korpáš and Tomori (1979), cough is the most
important airway protective reflex which provides airway
defensive responses to nociceptive stimuli. They recognized that
active expiratory efforts, due to the activation of caudal ventral
respiratory group (cVRG) expiratory premotoneurons, are the
prominent component of coughs. Here, we discuss data
suggesting that neurons located in the cVRG have an essential
role in the generation of both the inspiratory and expiratory
components of the cough reflex. Some lines of evidence indicate
that cVRG expiratory neurons, when strongly activated, may
subserve the alternation of inspiratory and expiratory cough
bursts, possibly owing to the presence of axon collaterals. Of
note, experimental findings such as blockade or impairment of
glutamatergic transmission to the cVRG neurons lead to the view
that neurons located in the cVRG are crucial for the production of
the complete cough motor pattern. The involvement of
bulbospinal expiratory neurons seems unlikely since their
activation affects differentially expiratory and inspiratory muscles,
while their blockade does not affect baseline inspiratory activity.
Thus, other types of cVRG neurons with their medullary
projections should have a role and possibly contribute to the fine
tuning of the intensity of inspiratory and expiratory efforts.
The purpose of the work is to establish the correlation between the change of absolute rotation poles of major tectonic plates based on continuous GNSS stations data. The work investigates 2804 continuous GNSS stations located on Pacific, North American, Eurasian, African, Antarctic, Australian and South American plates during 2002-2021. The components of recent horizontal displacements of continuous GNSS stations have been determined and a map of their distribution pattern has been constructed. The absolute rotation pole in ITRF2014/IGS14 reference frame of the studied tectonic plates has been determined. The obtained values are in good agreement with modern plate models. The definition of average annual rotation poles has been developed and their analysis has been carried out to research the dynamics of their change in time. It has been established that the change in the average annual rotation poles of the North American, African and South American plates occurs synchronously, while their change is asynchronous to the Pacific plate. Simultaneous changes in the average annual rotation poles of Antarctic and African plates were have also been identified.
Beerkan infiltration runs could provide an incomplete description of infiltration with reference to either the near steady-state or the transient stages. In particular, the process could still be in the transient stage at the end of the run or some transient infiltration data might be loss. The Wu1 method and the BEST-steady algorithm can be applied to derive soil hydrodynamic parameters even under these circumstances. Therefore, a soil dataset could be developed using two different data analysis methods. The hypothesis that the Wu1 method and BEST-steady yield similar predictions of the soil parameters when they are applied to the same infiltration curve was tested in this investigation. For a sandy-loam soil, BEST-steady yielded higher saturated soil hydraulic conductivity, Ks, microscopic pore radius, λm, and depth of the wetting front at the end of the run, dwf, and lower macroscopic capillary length, λc, as compared with the Wu1 method. Two corresponding means differed by 1.2–1.4 times, depending on the variable, and the differences appeared overall from moderate to relatively appreciable, that is neither too high nor negligible in any circumstance, according to some literature suggestions. Two estimates of Ks were similar (difference by < 25%) when the gravity-driven vertical flow and the lateral capillary components represented the 71–89% of total infiltration. In conclusion, the two methods of data analysis do not generally yield the same predictions of soil hydrodynamic parameters when they are applied to the same infiltration curve. However, it seems possible to establish what are the conditions making the two methods similar.
Obesity increases the incidence of hypogonadism in men, and hypogonadism in turn plays a role in obesity. One of the first mechanisms proposed to explain this was a hypothesis based on the principle that obese men have higher estrogen levels, and that increased estrogens provide feedback to the hypothalamicpituitary-testicular axis, reducing the secretion of gonadotropins and leading to a decrease of overall testosterone levels. This concept has since been questioned, though never completely disproven. In this study we compared hormone levels in three groups of men with differing BMI levels (between 18-25, 25-29, and 30-39), and found correlations between lowering overall testosterone, SHBG and increased BMI. At the same time, there were no significant changes to levels of free androgens, estradiol or the gonadotropins LH and FSH. These findings are in line with the idea that estrogen production in overweight and obese men with BMI up to 39 kg/m2 does not significantly influence endocrine testicular function., Luboslav Stárka, Martin Hill, Hana Pospíšilová, Michaela Dušková., and Obsahuje bibliografii
Regarding the fact that gay men leave less offspring than straight men, it is appropriate to raise a question by which means is male homosexuality maintained in a population and what could eventually be its evolutionary role. The aim of this paper is to summarize theories that try to explain male homosexuality within the framework of evolution. Furthermore, it aims to critically evaluate the results of empirical research that support particular theories or give evidence against them. In the first part, the paper provides a review of knowledge about the genetic and immunological origins of male homosexuality which consequently serves as a theoretical base for the main part of the paper that pursues the five most influential evolutionary theories of male homosexuality. and Homosexuální orientace se vyznačuje trvalou citovou a sexuální náklonností k jedincům stej-ného pohlaví. Vzhledem k tomu, že homosexu-álně orientovaní muži zanechávají méně potom-stva než heterosexuálně orientovaní muži, je na místě si položit otázku, jakými mechanismy je mužská homosexualita v populaci udržována a jaký by případně mohl být její evoluční vý-znam – tedy zda a případně komu (když ne ho-mosexuálnímu jedinci) přináší výhodu ve smy-slu vyššího reprodukčního úspěchu. Cílem této přehledové studie je shrnout teorie, jež se snaží mužskou homosexualitu vysvětlit v evolučním rámci, a kriticky zhodnotit výsledky empiric-kých výzkumů, které podporují jednotlivé teo-rie, či svědčí proti nim. Úvodní část článku po-skytuje přehled poznatků o genetickém a imu-nologickém původu homosexuality u mužů, rovněž však slouží jako teoretický základ pro hlavní část, která se věnuje pěti nejvlivnějším evolučním teoriím mužské homosexuality.