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4812. Choice and calibration of cyclic plasticity model with regard to subsequent fatigue analysis
- Creator:
- Halama, Radim, Šofer, Michal, and Fojtík, František
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- ratcheting, nonproportional hardening, consistent tangent modulus, low-cycle fatigue, and cyclic plasticity
- Language:
- English
- Description:
- Plasticity models, included in the most popular commercial FEM software, are not able to describe well such cyclic plasticity effects as multiaxial ratcheting or cyclic hardening caused by nonproportional loading. For example in the case of stainless steels it is necessary to use a robust cyclic plasticity model. This paper shows some iinteresting results from FE simulations of stress-strain behaviour of stainless steel 316L using new cyclic plasticity model with superposition of the kinematic hardening rule of AbdelKarim and Ohno [11] and the isotropic hardening rule of Calloch and Marquis [14]. On the basis of performed simulations, a fatigue study has been performed which shows the influence of material option in a FE computation on accuracy of life prediction. The conclusion presents recommendations for the calibration of cyclic plasticity models of Chaboche type. and Obsahuje seznam literatury
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
4813. Choleoeimeria salaselensis sp. n. (Apicomplexa: Eimeriidae) from the gall bladder of the horned viper Cerastes gasperettii (Serpentes: Viperidae) in Saudi Arabia
- Creator:
- Abdel-Baki, Abdel-Azeem S., Al-Quraishy, Saleh, and Duszynski, Donald W.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- Coccidia, oocysts, endogenous stages, taxonomy, and snakes
- Language:
- English
- Description:
- Oocyst morphology and endogenous developmental stages are described for Choleoeimeria salaselensis sp. n. from the gall bladder of 10 horned vipers, Cerastes gasperettii Leviton and Anderson, in Saudi Arabia. Sporulated oocysts are ellipsoidal, 23 × 15 (22-25 × 14-17) µm, length/width ratio (L/W) 1.5 (1.4-1.6), each with 4 sporocysts (Eimeria-like), but lack a micropyle, polar granules and oocysts residuum. Sporocysts are ellipsoidal, 8 × 5 (7-9 × 5-6) µm, L/W 1.5 (1.4-1.6), and Stieda, substieda and parasubstieda bodies are all absent, but a longitudinal suture, which divided the sporocysts into 2 plates, is present. Endogenous development is confined to epithelial cells in the bile duct and gall bladder; mature meronts were 11 × 7 µm, each with 10-16 merozoites, microgamonts were ~12 µm wide, and macrogamonts were ~16 µm wide with a prominent nucleus and wall-forming bodies. Given these two diagnostic features, sporocysts with a suture and composed of two plates and endogenous development limited to the biliary epithelium, we believe this coccidium is best classified as a member of Choleoeimeria Paperna et Landsberg, 1989. There are 5 known Eimeria species from vipers that have sporocysts somewhat similar in size to those of our new form, but all of them have much larger oocysts and larger sporocysts, some of which differ significantly in shape; there are not yet any Choleoeimeria species known from the Viperidae.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
4814. Cholesterol efflux and macrophage polarization in human adipose tissue
- Creator:
- Králová, Anna, Bartušková, Hana, Kauerová, Soňa, Janoušek, Libor, Froněk, Jiří, Králová Lesná, Ivana, and Poledne, Rudolf
- Format:
- počítač and online zdroj
- Type:
- model:article and TEXT
- Subject:
- cholesterol efflux, pro-inflammatory macrophages, conditioned media, visceral adipose tissue, and adipocyte size
- Language:
- English
- Description:
- The pro-inflammatory status of adipose tissue (AT) has been found to be related to reverse cholesterol transport (RCT) from peritoneal macrophages. However, this finding was made in experimental models using induced peritonitis and isolated peritoneal macrophages of animals. This experimental relationship is in agreement with RCT changes in man in two extreme situations, sepsis or cardiovascular complications. Given the above, we sought to test RTC in relationship to macrophage polarization in the visceral AT (VAT) of living kidney donors (LKDs) and the effect of conditioned media obtained from their AT. The influence of ATCM on CE capacity was first assessed in an experiment where standard plasma was used as cholesterol acceptor from [14C] cholesterol labeled THP-1 cells. Conditioned media as a product of LKDs’ incubated AT showed no effect on CE. Likewise, we did not find any effect of individual plasma of LKDs on CE when individual plasma of LKDs were used as acceptors. On the other hand, we documented an effect of LKDs’ adipose cell size on CE. Our results indicate that the pro-inflammatory status of human AT is not likely induced by disrupted RCT but might be influenced by the metabolic status of LKDs’ adipose tissue.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
4815. Cholesterol lowering and the vessel wall: new insights and future perspectives
- Creator:
- Tomáš Štulc and Richard Češka
- Format:
- print, bez média, and svazek
- Type:
- article, články, model:article, and TEXT
- Subject:
- Fyziologie člověka a srovnávací fyziologie, cholesterol, ateroskleróza, endoteliální dysfunkce, akutní koronární syndromy, atherosclerosis, endothelial dysfunction, acute coronary syndromes, cholesterol lowering, plaque stability, 14, and 612
- Language:
- English
- Description:
- The basis for most acute coronary events is either rupture or fissuring of unstable atherosclerotic plaques with subsequent thrombosis leading to coronary artery occlusion. The development of atherosclerotic plaques takes several decades, but the mechanical features determining its stability and the risk of rupture can change very rapidly depending on a number of internal factors. Unstable plaques have a large lipid core, a thin overlying fibrous cap and an abundance of inflammatory cells. The most important factor determining the plaque stability is the plasma level of atherogenic LDL particles. Increased levels of these particles cause endothelial dysfunction with impaired vasodilatation capacity and prevalence of vasoconstriction, maintain inflammatory infiltration of the plaque, impair the strength of the fibrous cap and facilitate aggregation and coagulation. Effective lowering of plasma cholesterol by pharmacological and non-pharmacological means can revert most of these processes and increase the plaque's mechanical stability within several hours to days. Lipid lowering therapy can therefore decrease the risk of acute coronary events within a very short space of time. Thus a radical decrease in lipid levels, along with modification of other risk factors, may become the cornerstone for treatment of acute coronary syndromes, in addition to being an effective treatment in primary and secondary prevention of coronary heart disease (CHD)., T. Štulc, R. Češka., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
4816. Cholesterol má tvár boha Janusa
- Creator:
- Ginter, Emil
- Type:
- article, model:article, and TEXT
- Language:
- Czech
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
4817. Chomout z plyše
- Creator:
- Komárek, Stanislav
- Type:
- article, model:article, and TEXT
- Language:
- Czech
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
4818. Chondracanthid copepod parasites of dories (Zeiformes: Zeidae) with the description of a new species of Chondracanthus from waters off northern Argentina
- Creator:
- Braicovich, Paola E., Lanfranchi, Ana L., Incorvaia, Inés S., and Timi, Juan T.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- Copepoda, taxonomy, South America, zeids, marine fish, host range, and zoogeographical distribution
- Language:
- English
- Description:
- A new species of parasitic copepod, Chondracanthus hoi sp. n. (Copepoda: Chondracanthidae), is described based on specimens of both sexes collected from the buccal cavity and gill arches of the silvery john dory, Zenopsis conchifer (Lowe) (Zeiformes: Zeidae), from waters off northern Argentina (35-36°S, 53-54°W). Female of C. hoi differs from its congeners by the following combination of characters: presence of five pairs of trunk processes, antennule with four knobs tipped with small setae and absence of denticles on the terminal process of maxilla. Chondracanthids and zeiform fishes have been proposed as an example of co-speciation; this assumption is derived from a series of analyses based on incomplete records of both geographical distribution and host range of some parasite species, as well as misidentification of fish hosts. These inconsistences observed during our bibliographical analyses are also discussed.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
4819. Chondroitinase ABC treatment and the phenotype of neural progenitor cells isolated from injured rat spinal cord
- Creator:
- Lucia Slovinská, Ivana Novotná, and Dáša Čížková
- Format:
- Type:
- article, články, model:article, and TEXT
- Subject:
- Fyziologie člověka a srovnávací fyziologie, poranění míchy, spinal cord injuries, enzyme chondroitinase ABC, neural progenitors cells, 14, and 612
- Language:
- English
- Description:
- The aim of the present study was to investigate whether enzyme chondroitinase ABC (ChABC) treatment influences the phenotype of neural progenitor cells (NPCs) derived from injured rat spinal cord. Adult as well as fetal spinal cords contain a pool of endogenous neural progenitors cells, which play a key role in the neuroregenerative processes follow ing spinal cord injury (SCI) and hold particular promise for therapeutic approaches in CNS injury or neurodegenerative diso rders. In our study we used in vitro model to demonstrate the differentiation potential of NPCs isolated from adult rat spinal cord after SCI, treated with ChABC. The intrathecal delivery of ChABC (10 U/ml) was performed at day 1 and 2 after SCI. The present findings indicate that the impact of SCI resulted in a decrease of all NPCs phenotypes and the ChABC treatment, on the contra ry, caused an opposite effect., L. Slovinská, I. Novotná, D. Čížková., and Obsahuje bibliografii a bibliografické odkazy
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
4820. Chondrostoma almacai, a new czprinid species from the southwest of Portugal, Iberian Peninsula
- Creator:
- Coelho, Maria M., Mesquita, Natacha, and Collares-Pereira, Maria J.
- Type:
- article and TEXT
- Subject:
- Chondrostoma lusitanicum, Cyprinidae, endangered, endemic, and morphological markers
- Language:
- English
- Description:
- A new species of Iberian cyprinid fish, Chondrostoma almacai, from the southwest of Portugal is described. Distribution area includes the Mira, Arade and Bensafrim drainages, previously considered to be inhabited by another phylogenetically related taxon, Chondrostoma lusitanicum. Chondrostoma almacai sp. nov. and C. lusitanicum present important morphological similarities, though significant differences were found for meristic and morphometric characters. The main diagnostic characters for C. almacai are the higher number of scales on the lateral line and above the lateral line, the lower number of right pharyngeal teeth, the longer snout and the smaller head depth. Furthermore, the new species has a small number of gill rakers and a larger predorsal distance, pelvic fin length and eye diameter. Previous molecular data, both mtDNA and nuclear markers (allozymes), suggested that C. almacai and C. lusitanicum are strongly differentiated sister-species. The morphological variability and geographic distribution of C. lusitanicum are reviewed and the most southerly populations from the southwest of Portugal are now recognized as the new species, C. almacai. It is recommended that both species be considered Critically Endangered according to the IUCN Red List Categories and Criteria [B1ab(ii,iii,iv)c(iv)+2ab(ii,iii,iv)c(iv) for C. almacai and A2ce+3ce+4ce for C. lusitanicum].
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/