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30992. Ten years of our translational research in the field of veno-arterial extracorporeal membrane oxygenation
- Creator:
- Kittnar, Otomar
- Format:
- počítač and online zdroj
- Type:
- model:article and TEXT
- Subject:
- translational medicine, extracorporeal life support, VA ECMO, and heart failure
- Language:
- English
- Description:
- Extracorporeal life support is a treatment modality that provides prolonged blood circulation, gas exchange and can substitute functions of heart and lungs to provide urgent cardio-respiratory stabilization in patients with severe but potentially reversible cardiopulmonary failure refractory to conventional therapy. Generally, the therapy targets blood pressure, volume status, and end-organs perfusion. As there are significant differences in hemodynamic efficacy among different percutaneous circulatory support systems, it should be carefully considered when selecting the most appropriate circulatory support for specific medical conditions in individual patients. Despite severe metabolic and hemodynamic deterioration during prolonged cardiac arrest, venoarterial extracorporeal membrane oxygenation (VA ECMO) can rapidly revert otherwise fatal prognosis, thus carrying a potential for improvement in survival rate, which can be even improved by introduction of mild therapeutic hypothermia. In order to allow a rapid transfer of knowledge to clinical medicine two porcine models were developed for studying efficiency of the VA ECMO in treatments of acute cardiogenic shock and progressive chronic heart failure. These models allowed also an intensive research of adverse events accompanying a clinical use of VA ECMO and their possible compensations. The results indicated that in order to weaken the negative effects of increased afterload on the left ventricular function the optimal VA ECMO flow in cardiogenic shock should be as low as possible to allow adequate tissue perfusion. The left ventricle can be also unloaded by an ECG-synchronized pulsatile flow if using a novel pulsatile ECMO system. Thus, pulsatility of VA ECMO flow may improve coronary perfusion even under conditions of high ECMO blood flows. And last but not least, also the percutaneous balloon atrial septostomy is a very perspective method how to passively decompress overloaded left heart.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
30993. Tendency and consequences of superparasitism for the parasitoid Ooencyrtus pityocampae (Hymenoptera: Encyrtidae) in parasitizing a new laboratory host, Philosamia ricini (Lepidoptera: Saturniidae)
- Creator:
- Tunca, Hilal, Buradino, Maurane, Colombel Etty-Ambre, and Tabone, Elisabeth
- Format:
- print, počítač, and online zdroj
- Type:
- article, články, journal articles, model:article, and TEXT
- Subject:
- Zoologie, blanokřídlí, motýli, Hymenoptera, butterflies, Encyrtidae, Ooencyrtus pityocampae, Lepidoptera, Saturniidae, Philosamia ricini, self-superparasitism, host density, female age, offspring fitness, 2, and 59
- Language:
- English
- Description:
- The tendency for self-superparasitism and it's effects on the quality of the parasitoid Ooencyrtus pityocampae (Mercet) (Hymenoptera: Encyrtidae) in parasitizing a new laboratory host, Philosamia ricini (Danovan) (Lepidoptera: Saturniidae), were investigated. In this study, female parasitoids of various ages (1-, 3- and 5-day-old) were tested individually. Parasitoids were provided with 1-day-old P. ricini eggs at ratios of 5, 10, 20, 30 and 40 host eggs per wasp. The tendency to superparasitize was dependent on the female's age and host density. Five-day-old females showed a strong tendency to superparasitize at low host densities. The development time of wasps in superparasitized eggs was longer than that of wasps in singly parasitized eggs. The size and longevity of adult parasitoids decreased significantly with superparasitism. This work contributes to the development of an efficient mass rearing and laboratory rearing of the parasitoid O. pityocampae using a new host., Hilal Tunca, Maurane Buradino, Etty-Ambre Colombel, Elisabeth Tabone., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
30994. Tenké vrstvy a povrchy
- Creator:
- Kočka, Jan, Cháb, Vladimír, and Chvoj, Zdeněk
- Format:
- print, bez média, and svazek
- Type:
- model:article and TEXT
- Subject:
- fyzika, dějiny, physics, history, 6, and 53
- Language:
- Czech and English
- Description:
- Jan Kočka, Vladimír Cháb, Zdeněk Chvoj.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
30995. Tenké vrstvy a tenkovrstvové nanoštruktúry pre kryoelektroniku a senzoriku
- Creator:
- Plecenik, A., Gregor, M., and Kúš, P.
- Format:
- print, bez média, and svazek
- Type:
- model:article and TEXT
- Subject:
- Univerzita Komenského v Bratislave., Katedra experimentálnej fyziky, experimentální fyzika, nanotechnologie, tenké vrstvy, experimental physics, nanotechnology, thin films, 6, and 53
- Language:
- Czech
- Description:
- A. Plecenik, M. Gregor, P. Kúš a kol.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
30996. Tenké vrstvy PZT připravené iontovým naprašováním z vícesložkového terče
- Creator:
- Hlubuček, Jiří, Vápenka, David, Horodyská, Petra, and Václavík, Jan
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- PZT, multicomponent target, ion beam sputtering, control of stoichiometry, naprašování iontovým svazkem, vícesložkový terč, řízení chemického složení, and přebytek olova
- Language:
- Czech
- Description:
- Lead zirconatetitanate (PZT) is widely used for its ferroelectric and piezoelectric properties. Its unique properties are conditioned by perovskite structure. Crystallization into this phase is determined among others by a proper stoichiometry, where the lead concentration is a crucial parameter. That is why this paper is devoted to the control of chemical composition of PZT thin films deposited via ion beam sputtering (IBS). Our study showed that the determinative lead content in PZT films prepared by ion-beam sputtering from a multicomponent target can be easily controlled by the power of primary ion source. At the same time, the composition is also dependent on the substrate temperature and the power of assistant ion source. and Olovo zirkonát-titanát (PZT) je široce používaný pro svoje feroelektrické a piezoelektrické vlastnosti, které jsou podmíněny perovskitovou strukturou. Krystalizace PZT do této preferované fáze je podmíněna mimo jiné také správným stechiometrickým složením, kde koncentrace olova je kritickým parametrem. Samotný proces krystalizace probíhá při vysokoteplotním žíhání, při kterém ovšem dochází k nežádoucímu snížení obsahu olova v deponované vrstvě. Proto je dobré připravit vrstvu s přebytkem olova, a tím tak kompenzovat jeho úbytek při žíhání. Z toho důvodu je tento článek zaměřen na řízení chemického složení tenkých filmů PZT pomocí naprašování iontovým svazkem (IBS). Vrstvy nanesené pomocí IBS by měly teoreticky vykazovat stejné chemické složení jaké má terč, z kterého jsou nanášeny. Nicméně, v případě PZT je vhodné mít možnost kontrolovaně měnit chemické složení naprašovaných tenkých filmů pro dosažení vysokého perovskitového podílu. Naše studie odhalila, že určující obsah olova v PZT vrstvách, připravených pomocí jednoduché a duální iontové depozice z vícesložkového terče, může být snadno řízen výkonem primárního iontového zdroje. Složení je také závislé na teplotě substrátu a na energii iontů asistenčního iontového zdroje. Tenké PZT vrstvy byly připraveny s více než 30% přebytkem ze stechiometrického vícesložkového terče (tj. terč bez přebytku olova). Můžeme tedy navrhnout několik možných setů depozičních parametrů vhodných pro depozici PZT pomocí IBS pro dosažení vysokého perovskitového podílu.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
30997. Tensegritní struktury
- Creator:
- Wegenkittlová, Pavla and Vochozka, Vladimír
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Language:
- Czech
- Description:
- At first glance, tensegrity structures give the impression of levitation, but, of course, they do not deny gravity. They are a beautiful example of the application of basic physical laws and applying physical principles in practice. The term tensegrity refers to structures formed by rigid bodies under pressure in a network formed by mechanical tension.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
30998. Tensile and erosive strength of soil macro-aggregates from soils under different management system
- Creator:
- Urbanek, Emilia, Horn, Rainer, and Smucker, Alwin J.M.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- tensile strength, erosive strength, exterior/interior aggregate region, aggregate, concentric layers, dry aggregate stability, and reduced tillage
- Language:
- Slovak
- Description:
- Reduced soil tillage practices are claimed to improve soil health, fertility and productivity through improved soil structure and higher soil organic matter contents. This study compares soil structure stability of soil aggregates under three different tillage practices: conventional, reduced and no tillage. The erosive strength of soil aggregates has been determined using the abrasion technique with the soil aggregate erosion chambers (SAE). During abrasion soil aggregates have been separated into the exterior, transitional and interior regions. The forces needed to remove the material from the aggregate were calculated as erosive strength and compared with the tensile strength of the aggregates derived from crushing tests. The relationship between aggregate strength and other soil properties such as organic carbon and hydrophobic groups’ content has also been identified. The results show that erosive and tensile strength of soil aggregates is very low in topsoil under conventional and reduced tillage comparing with the subsoil horizons. Negative correlation was found between the content of organic carbon, hydrophobic compounds and erosive aggregate strength which suggests that the stabilising effect of soils organic carbon may be lost with drying. The positive relationship between the tensile strength and erosive strength for aggregates of 8–5 mm size suggests that the total strength of these aggregates is controlled by the sum of strength of all concentric layers.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
30999. Teologie, ekologie a smích Petra Ondoka: K nedožitým osmdesátinám
- Creator:
- Rejmánek, Marcel
- Type:
- article, model:article, and TEXT
- Language:
- Czech
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
31000. Teorém Cauchyho-Kowalevské a teorém Noetherové: Jak se jako žena (ne)proslavit ve světě matematiky?: Věnováno 100. výročí teorému Noetherové
- Creator:
- Beránková, Eliška
- Format:
- print, bez média, and svazek
- Type:
- model:article and TEXT
- Subject:
- Kovalevskaja, Sof‘ja Vasil‘jevna, 1850-1891, Noetherová, Emmy, 1882-1935, fyzika, matematika, dějiny vědy, physics, mathematics, history of science, 6, and 53
- Language:
- Czech
- Description:
- Tento článek se věnuje historickému kontextu vzniku a přijetí teorému Cauchyho-Kowalevské a teorému Noetherové, dvou jedinečných výsledků, které zásadně ovlivnily moderní matematiku i matematickou a teoretickou fyziku. Autorkami těchto teorémů jsou dvě ženy, Sofie Kowalevská a Emmy Noetherová, které si v době, kdy ženy jen stěží dosahovaly vyššího vzdělání, svým talentem, houževnatostí a úsilím dokázaly vybojovat místo ve vědeckém světě a navždy se zapsaly do historie přírodních věd., The article covers the historical context ot the establishment and recognition of the Cauchy-Kowalevsky theorem and Noether theorem, two unique research results, which have essentially influenced modern mathematics, and mathematical and theoretical physics. The authors of theorems are two women, Sofie Kowalevsky and Emmy Noether who in a time when women barely reached higher education, achieved positions in the scientific world and forever influenced the history of natural sciences., Eliška Beránková., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public