Present state of investment casting technology - ceramic moulds

Tato bakalářská práce si klade za cíl shromáždit základní informace o současné problematice výroby keramických skořepinových forem. Je zaměřena na přehled základních materiálů a nejmodernějších zařízení používaných při jejich výrobě. Dále se práce zaobírá možnými problémy, popřípadě defekty, které při výrobě skořepiny mohou nastat.This bachelor thesis is focused to the production of ceramic moulds and connected problems during the shelling process. The survey of materials and equipment is given in this work and also possible defects and their causes in the ceramic shells.

Identification DNA of Plant and Animal Species in Food by Polymerase Chain Reaction

Na tři potravinové alergeny rostlinného původu – soju, pistácie a mandle – jsme vyvíjeli metody na jejich detekování v potravinách. Na detekci sóje (Glycine max) v potravinách jsme použili real-time PCR orientovanou na gen lec kódující lektin specifický pro sóju. Na tuto cílovou sekvenci byl orientovaný PCR systém s primery Le2F a Le2R a se sondou Le2P typu Taqman. Byla stanovena inkluzivita i exkluzivita systému, dále byl zjištěn detekční limit (2,75 pg) a praktický detekční limit (0,02 %). Celý navržený systém pak byl kvantifikován. Na detekci pisácií (Pistacia) byla použita real-time PCR založená na primerech a sondě orientované na gen COR kódující dehidrin. Byla stanovena inkluzivita i exkluzivita systému, dále byl zjištěn detekční limit (3,5 pg) a praktický detekční limit (0,002 %). Na detekci mandlí (Amygdalus) se nepodařilo vyvinout žadný systém, který by 100 % splňoval všechny kvalitativní parametry.We were developing detection methods for three food allergens of plant origin. We used real-time PCR for soy detection in food oriented on gene lec, that is coding lektine specific for soy. On this target sequence were oriented PCR system with primers Le2F and Le2R and TaqMan probe Le2P. Detection limit (2,75 pg), practical detection limit (0,02 %), inclusivity and exclusivity were determined. Whole system were quantified. Real-time PCR for pistachio detection were based on primers and probe for gene COR. Detection limit (3,5 pg), practical detection limit (0,002 %), inclusivity and exclusivity were determined. For almond detection we were not succeed system, that fulfil all qualitative parametres.

Prevalence of Atrial Fibrillation as a Risk Factor in Patients after Circulatory Arrest for Ventricular Fibrillation

Fibrilace síní je nejčastější arytmií vyskytující se v dospělé populaci a náhlé srdeční úmrtí patří mezi nejčastěji se vyskytující příčinu kardiovaskulárního úmrtí, na kterém se podílí až z 50%. V řadě studií byla sledována spojitost mezi fibrilací síní a dalšími onemocněními srdce včetně náhlého srdečního úmrtí. V populaci narůstá prevalence i incidence fibrilace síní a je spojována s vyšší morbiditou i mortalitou nemocných. Patofyziologické mechanismy u fibrilace síní jsou velmi komplexní a jsou propojeny s řadou dalších onemocnění, s nimiž mohou mít částečně společný základ a mohou se navzájem ovlivňovat. Vyšší výskyt fibrilace síní je popisován zejména u pacientů s ICHS, srdečním selháním, arteriální hypertenzí. Zvýšená mortalita či vyšší výskyt komorových arytmií včetně fibrilace komor jsou popsány i v pracích u nositelů ICD, ale i v běžné populaci, kde byla fibrilace síní prokázána jako nezávislý rizikový faktor spojený až s 3násobným rizikem fibrilační zástavy oběhu. Tato práce se snaží přinést ucelený obraz vztahu fibrilace síní a náhlého srdečního úmrtí. Přináší informace o základní anatomii, fyziologii elektrické aktivity srdce, epidemiologii výskytu a patofyziologii fibrilace síní a komorových arytmií. Cílem této práce bylo zanalyzovat výskyt fibrilace síní jako rizikového faktoru u...Atrial fibrillation is the most common arrhythmia occurring in the adult population. Sudden cardiac death is one of the most common causes of cardiovascular death, accounting for up to 50% of all cardiovascular deaths. A number of trials have investigated the association between atrial fibrillation and other heart diseases, including sudden cardiac death. Atrial fibrillation is increasing in prevalence and incidence in the population and is associated with higher morbidity and mortality in patients. The pathophysiological mechanisms in atrial fibrillation are very complex and are linked to a number of other diseases. With these diseases they may share a common background and may interact together. A higher incidence of atrial fibrillation is described especially in patients with coronary artery disease, heart failure, and arterial hypertension. Increased mortality or higher incidence of ventricular arrhythmias, including ventricular fibrillation, has been described in studies in ICD carriers, but also in the general population, where atrial fibrillation has been shown to be an independent risk factor associated with up to a 3-fold increased risk of AF. This paper want to provide a comprehensive picture of the relationship between atrial fibrillation and sudden cardiac death. It provides information...Kardiologická klinikaLékařská fakulta v PlzniFaculty of Medicine in Pilse

Systematika, fylogeneze a biogeografie gekonů rodu Hemidactylus (Reptilia, Gekkonidae) z Arábie a Blízkého východu.

(in English) Until relatively recently, the gecko genus Hemidactylus was considered to contain only several hard-to-distinguish species in the eastern Mediterranean and the Arabian Peninsula. This was mostly given by the apparent morphological uniformity of the geckos in combination with their often synanthropic lifestyle, which facilitated the dispersal of some of the species over large ranges. However, our understanding of the diversity of the genus was about to change with the onset of molecular phylogenetic methods that became extensively available and routinely applied to tackle the questions of systematics and phylogeny of all kinds of organisms. This thesis focuses on resolving the phylogeny, systematics, and biogeography of the Arabian Hemidactylus. Using an unprecedented sampling of over 500 samples of more than 40 Hemidactylus species from the eastern Mediterranean, Arabian Peninsula, Socotra, North and East Africa and Iran and sequencing up to six genes (two mitochondrial - 12S rRNA, cyt b; four nuclear - cmos, mc1r, rag1, rag2) I reconstructed the time-calibrated phylogeny of the arid clade of Hemidactylus, inferred its complex biogeographical history in the region, and detected seven potentially new species. The results of the biogeographic analyses indicate that the current...(in Czech) Donedávna byli gekoni rodu Hemidactylus vyskytující se v oblasti východního Mediteránu a na Arabském poloostrově považováni za relativně nediverzifikovanou skupinu. Jednak to bylo způsobeno jejich výraznou morfologickou uniformitou a zároveň jejich často synantropním způsobem života, díky kterému byly některé druhy rozšířeny na velké vzdálenosti. Nicméně s nástupem molekulárně-fylogenetických metod jakožto běžné techniky rutinně používané k odhalování fylogenetických vztahů mezi organismy se naše poznání diverzity tohoto rodu radikálně změnilo. Cílem této práce bylo odhalit fylogenetické a biogeografické vztahy a systematiku arabských zástupců rodu Hemidactylus. Analýzou přes 500 jedinců více než 40 druhů pocházejících z východního Mediteránu, Arabského poloostrova, Sokotry, severní a východní Afriky a Íránu a sekvencí šesti genů (dva mitochondriální - 12S rRNA, cyt b; čtyři jaderné - cmos, mc1r, rag1, rag2) se podařilo rekonstruovat kalibrovanou fylogenezi tzv. aridního kladu rodu Hemidactylus, odvodit jeho komplexní biogeografickou historii a odhalit sedm potenciálně nových druhů. Výsledky biogeografické analýzy naznačují, že současné rozšíření rodu bylo formováno jak vikariančními tak disperzními událostmi. Vikarianční události je možné dát do souvislosti s kontinentálním rozpadem v...Department of ZoologyKatedra zoologieFaculty of SciencePřírodovědecká fakult

Possibilities of using modern methods in manufacturing of prototype castings

Úvod diplomové práce je zaměřen na přehled používaných technologií v oblasti slévárenství. Jsou zde také popsány principy jednotlivých metod, přičemž metoda FDM je rozebrána podrobněji. Tato metoda byla následně použita v praktické části k výrobě voskových modelů pomocí silikonové formy. Voskové modely byly poté použity k výrobě odlitků metodou vytavitelného lití. Výsledkem této práce je stanovení rozměrových změn v průběhu celé výroby od výkresové dokumentace po skutečný odlitek.The introduction part of the thesis focuses on the overview of rapid prototyping in foundry industry. Principles of the most important RP methods are described and the FDM method is analyzed in more detail. This method was used in the practical part for the production of wax patterns with silicone moulds. The wax patterns were used for the production of castings using the lost wax method. The result of this work is determination of dimensional changes during the whole process of casting manufacture from the drawing to the final casting.

Karst and Caves in Salt Diapirs, SE Zagros Mts. (Iran)

Na področju Perzijskega zaliva je znanih okoli 200 solnih diapirjev, med njimi mnogo aktivnih. Kraške kamnine predstavljajo največ kamena sol in redkeje sadra ter anhidrid. Kraške oblike, popolnoma primerljive z oblikami v “klasičnih” karbonatnih kamninah, so najbolje razvite v ostankih uravnanih površij. Tako so škraplje, “solution pipes”, vrtače, udorne vrtače, depresije podobne uvalam in poljem, slepe doline, soteske, ponori, izviri in jame. Tod sta bili odkriti in raziskani dve izmed najdaljših jam v soli na svetu. Daljše jame so nastale predvsem v piezometrični gladini, večje pa v diapirjih ob morski obali. Jame pogosto predstavljajo odtok iz depresij, podobnih poljem. V dnu udornih vrtač in v ponorih so tudi strme, skoraj navpične jame. Kraški procesi so omejeni predvsem na sol, redkeje na sadro. Predvsem gre za raztapljanje in odnašanje soli izpod neprepustnega pokrova (gypcrete). V nekaterih diapirjih je dokazano globoko kroženje padavinske vode.About 200 salt diapirs (plugs) have been known in the region of the Persian Gulf. numerous are still active. Karst rocks are represented by a rock salt, less frequently by gypsum and anhydrite. Karst developed especially in relics of planated surfaces. Karst forms are completely comparable with karsts in classical carbonate rocks. Different forms can be distinguished: karren, solution pipes, solution dolines, solution-collapse dolines, uvalalike to polje-like depressions, blind valleys, canyon-like forms, ponors, springs and caves. Two World longest caves in salt were discovered and explored here. Long caves are developed especially in a watertable, large ones in plugs near the seacoast. Caves are often outlets of closed depressions (polje-like). Some caves at bottoms of collapse-solution dolines or swallow holes are subvertical. Karst processes are caused dominantly by dissolution of salt, less frequently of gypsum. The process of subrosion of halite under gypcretes plays the main role. Deep circulation of meteoric waters was proved in some plugs

Two newly recognized species of Hemidactylus (Squamata, Gekkonidae) from the Arabian Peninsula and Sinai, Egypt

This is an open access article distributed under the terms of the Creative Commons Attribution License 3.0 (CC-BY), which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.A recent molecular phylogeny of the Arid clade of the genus Hemidactylus revealed that the recently described H. saba and two unnamed Hemidactylus species from Sinai, Saudi Arabia and Yemen form a well-supported monophyletic group within the Arabian radiation of the genus. The name 'Hemidactylus saba species group' is suggested for this clade. According to the results of morphological comparisons and the molecular analyses using two mitochondrial (12S and cytb) and four nuclear (cmos, mc1r, rag1, rag2) genes, the name Hemidactylus granosus Heyden, 1827 is resurrected from the synonymy of H. turcicus for the Sinai and Saudi Arabian species. The third species of this group from Yemen is described formally as a new species H. ulii sp. n. The phylogenetic relationships of the members of 'Hemidactylus saba species group' are evaluated and the distribution and ecology of individual species are discussed. © Jiří Šmíd et al.The study was supported by the NAKI project of the Ministry of Culture of the Czech Republic (# DF12P01OVV021 MKČR to JŠ and JM), by grant CGL2012-36970 to SC from the Ministerio de Economía y Competitividad, Spain (co-funded by FEDER). We are thankful to the Deanship of academic research at Taif University for funding the sample collection in Saudi Arabia (Grant no. 1-433-2108) and to Omer Baeshen, Environment Protection Agency, Sana'a, Republic of Yemen for issuing the collecting permit (Ref 10/2007).Peer Reviewe

Contributions to ophiology in Zootaxa 2001–2020: patterns and trends

There are currently 3,900 recognized, extant snake species belonging to 529 genera globally (Uetz et al. 2021; this study), making snakes one of the most diverse major groups of squamates. Of the 665 currently recognized species that were described between 2001 and 2020 (a ~17% increase in total species), ~34% of these (226 species) were described in Zootaxa. This number does not include species resurrected from synonymy. The other ~66% (439) species were described in 105 other journals, bulletins or books (Fig.1a). Overall, the number of new snake species described every year is gradually increasing, and 40% of the new species described since 2011 were published in Zootaxa. Following Zootaxa, the second ranked journal, with 37 described species since 2001, is Herpetologica (Fig. 2). Anecdotally, the choice of Zootaxa as a publication outlet for new species descriptions by most authors is based on speed of publication post-acceptance, publication free of charge, relatively unconstrained number of papers published per year, relatively unconstrained manuscript length, expert section editors and reviewers, and consolidated scientometric parameters.Peer reviewe

Diversity, distribution and conservation of the terrestrial reptiles of Oman (Sauropsida, Squamata)

All authors: Salvador Carranza , Meritxell Xipell, Pedro Tarroso, Andrew Gardner, Edwin Nicholas Arnold, Michael D. Robinson, Marc Simó-Riudalbas, Raquel Vasconcelos, Philip de Pous, Fèlix Amat, Jiří Šmíd, Roberto Sindaco, Margarita Metallinou †, Johannes Els, Juan Manuel Pleguezuelos, Luis Machado, David Donaire, Gabriel Martínez, Joan Garcia-Porta, Tomáš Mazuch, Thomas Wilms, Jürgen Gebhart, Javier Aznar, Javier Gallego, Bernd-Michael Zwanzig, Daniel Fernández-Guiberteau, Theodore Papenfuss, Saleh Al Saadi, Ali Alghafri, Sultan Khalifa, Hamed Al Farqani, Salim Bait Bilal, Iman Sulaiman Alazri, Aziza Saud Al Adhoobi, Zeyana Salim Al Omairi, Mohammed Al Shariani, Ali Al Kiyumi, Thuraya Al Sariri, Ahmed Said Al Shukaili, Suleiman Nasser Al Akhzami.In the present work, we use an exceptional database including 5,359 records of 101 species of Oman’s terrestrial reptiles together with spatial tools to infer the spatial patterns of species richness and endemicity, to infer the habitat preference of each species and to better define conservation priorities, with especial focus on the effectiveness of the protected areas in preserving this unique arid fauna. Our results indicate that the sampling effort is not only remarkable from a taxonomic point of view, with multiple observations for most species, but also for the spatial coverage achieved. The observations are distributed almost continuously across the two-dimensional climatic space of Oman defined by the mean annual temperature and the total annual precipitation and across the Principal Component Analysis (PCA) of the multivariate climatic space and are well represented within 17 out of the 20 climatic clusters grouping 10% of the explained climatic variance defined by PC1 and PC2. Species richness is highest in the Hajar and Dhofar Mountains, two of the most biodiverse areas of the Arabian Peninsula, and endemic species richness is greatest in the Jebel Akhdar, the highest part of the Hajar Mountains. Oman’s 22 protected areas cover only 3.91% of the country, including within their limits 63.37% of terrestrial reptiles and 50% of all endemics. Our analyses show that large areas of the climatic space of Oman lie outside protected areas and that seven of the 20 climatic clusters are not protected at all. The results of the gap analysis indicate that most of the species are below the conservation target of 17% or even the less restrictive 12% of their total area within a protected area in order to be considered adequately protected. Therefore, an evaluation of the coverage of the current network of protected areas and the identification of priority protected areas for reptiles using reserve design algorithms are urgently needed. Our study also shows that more than half of the species are still pending of a definitive evaluation by the International Union for Conservation of Nature (IUCN).This work was funded by grants CGL2012-36970, CGL2015-70390-P from the Ministerio de Economía y Competitividad, Spain (cofunded by FEDER) to SC, the project Field study for the conservation of reptiles in Oman, Ministry of Environment and Climate Affairs, Oman (Ref: 22412027) to SC and grant 2014-SGR-1532 from the Secretaria d'Universitats i Recerca del Departament d'Economia i Coneixement de la Generalitat de Catalunya to SC. MSR is funded by a FPI grant from the Ministerio de Economía y Competitividad, Spain (BES-2013-064248); RV, PT and LM were funded by Fundação para a Ciência e Tecnologia (FCT) through post-doc grants (SFRH/BPD/79913/2011) to RV, (SFRH/BPD/93473/2013) to PT and PhD grant (SFRH/BD/89820/2012) to LM, financed by Programa Operacional Potencial Humano (POPH) – Quadro de Referência Estrategico Nacional (QREN) from the European Social Fund and Portuguese Ministerio da Educação e Ciência

Reductive Evolution of the Mitochondrial Processing Peptidases of the Unicellular Parasites Trichomonas vaginalis and Giardia intestinalis

Mitochondrial processing peptidases are heterodimeric enzymes (α/βMPP) that play an essential role in mitochondrial biogenesis by recognizing and cleaving the targeting presequences of nuclear-encoded mitochondrial proteins. The two subunits are paralogues that probably evolved by duplication of a gene for a monomeric metallopeptidase from the endosymbiotic ancestor of mitochondria. Here, we characterize the MPP-like proteins from two important human parasites that contain highly reduced versions of mitochondria, the mitosomes of Giardia intestinalis and the hydrogenosomes of Trichomonas vaginalis. Our biochemical characterization of recombinant proteins showed that, contrary to a recent report, the Trichomonas processing peptidase functions efficiently as an α/β heterodimer. By contrast, and so far uniquely among eukaryotes, the Giardia processing peptidase functions as a monomer comprising a single βMPP-like catalytic subunit. The structure and surface charge distribution of the Giardia processing peptidase predicted from a 3-D protein model appear to have co-evolved with the properties of Giardia mitosomal targeting sequences, which, unlike classic mitochondrial targeting signals, are typically short and impoverished in positively charged residues. The majority of hydrogenosomal presequences resemble those of mitosomes, but longer, positively charged mitochondrial-type presequences were also identified, consistent with the retention of the Trichomonas αMPP-like subunit. Our computational and experimental/functional analyses reveal that the divergent processing peptidases of Giardia mitosomes and Trichomonas hydrogenosomes evolved from the same ancestral heterodimeric α/βMPP metallopeptidase as did the classic mitochondrial enzyme. The unique monomeric structure of the Giardia enzyme, and the co-evolving properties of the Giardia enzyme and substrate, provide a compelling example of the power of reductive evolution to shape parasite biology