Technology of Gold Ores Dressing

Import 05/08/2014Téma této diplomové práce zní Technologie úpravy zlatonosných rud. První tři kapitoly teoretické části se zabývají obecným popisem významu zlata pro lidskou společnost, využitím zlata, charakteristikou zlata z chemického a mineralogického hlediska a jeho výskyt jako příměs v minerálech. Dále jsou zaměřeny na ložiska a těžbu zlata v České republice, ve světě a popis zkoumané lokality, ze které pochází materiál použitý v experimentální části. Čtvrtá kapitola obsahuje výčet možných metod úpravy zlata, které napomáhají získat kvalitní koncentráty ze zlatonosného ložiska. Experimentální část práce je orientovaná na laboratorní pokusy, které byly provedeny v rámci této diplomové práce. Cílem této kapitoly bylo vyhodnocení nejlepších flotačních sběračů, ověření vlivu otáček na výnos koncentrátu, přečistná flotace (získání nejkvalitnějšího koncentrátu), ověření hydrofobnosti zlata a doplňkové úpravnické metody – gravitační rozdružování pomocí odstředivých sil.The topic of this thesis was Technology of Gold Ores Dressing. The first three chapters of the theoretical part deals with a general description of the importance of gold for human society, gold usage, the chemical and mineralogical characterization characterization of gold and presence additive in minerals . Next part focuses on deposits and gold mining in the Czech Republic, in the world and a description of the investigated locality from which comes the material used for the experiments. The fourth chapter contains methods for processing of gold which help to get high quality concentrates from gold deposits. The experimental part of the work was focused on laboratory experiments that have been conducted in this thesis. The aims of this chapter were to evaluate the best flotation collectors, verification the effect of speed on the yield of concentrate, clearing flotation (gain the highest quality concentrate), verification hydrophobicity of gold and the gravity separation method using centrifugal forces.Prezenční542 - Institut hornického inženýrství a bezpečnostivýborn

Umbilical Cord Wharton’s Jelly Repeated Culture System: A New Device and Method for Obtaining Abundant Mesenchymal Stem Cells for Bone Tissue Engineering

<div><p>To date, various types of cells for seeding regenerative scaffolds have been used for bone tissue engineering. Among seed cells, the mesenchymal stem cells derived from human umbilical cord Wharton’s jelly (hUCMSCs) represent a promising candidate and hold potential for bone tissue engineering due to the the lack of ethical controversies, accessibility, sourced by non-invasive procedures for donors, a reduced risk of contamination, osteogenic differentiation capacities, and higher immunomodulatory capacity. However, the current culture methods are somewhat complicated and inefficient and often fail to make the best use of the umbilical cord (UC) tissues. Moreover, these culture processes cannot be performed on a large scale and under strict quality control. As a result, only a small quantity of cells can be harvested using the current culture methods. To solve these problems, we designed and evaluated an UC Wharton’s jelly repeated culture device. Using this device, hUCMSCs were obtained from the repeated cultures and their quantities and biological characteristics were compared. We found that using our culture device, which retained all tissue blocks on the bottom of the dish, the total number of obtained cells increased 15–20 times, and the time required for the primary passage was reduced. Moreover, cells harvested from the repeated cultures exhibited no significant difference in their immunophenotype, potential for multilineage differentiation, or proliferative, osteoinductive capacities, and final osteogenesis. The application of the repeated culture frame (RCF) not only made full use of the Wharton’s jelly but also simplified and specified the culture process, and thus, the culture efficiency was significantly improved. In summary, abundant hUCMSCs of dependable quality can be acquired using the RCF.</p></div

Immunophenotypic profiles of the T1-P3, T3-P3, and T5-P3 cells.

<p>Immunophenotypic profiles of the T1-P3, T3-P3, and T5-P3 cells.</p

The repeated culture frame and structure of umbilical cord.

<p>The repeated culture frame is shown in figures A and B, and figures C and D display in cultures. HE stained cross-section of an umbilical cord (E) shows the veins (F), arteries (G), amnion layer (H) and Wharton’s jelly (I), respectively. The right panel shows the IF staining of CD73 (J), CD90 (K), and CD105 (L) in the Wharton’s jelly. Figures M and N show uniform cell distribution in the suspended tissue block and cell distribution owards the bottom in adherent culture for 7 days, respectively. Scale bars: 2<b> </b>mm in E; 200 um in F–I; 20 um in J–L; and 200 um in M and N.</p

Primers Used for RT-PCR and Real-Time RT-PCR.

<p>ALP, alkaline phosphatase; RUNX2, runt-related transcription factor 2; ON, osteonectin; COL II, type II collagen; COL X, type X collagen; ACAN, aggrecan; LPL, lipoprotein lipase; PPAR-γ, peroxisome proliferator-activated receptor γ; OC, osteocalcin.</p><p>Primers Used for RT-PCR and Real-Time RT-PCR.</p