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Extraction of copper from the waste of the Karagayly concentrator under the action of an electric hydro-pulse discharge depending on the pH of the medium in the cell In the work, the waste of the Karagayly concentrator was processed at the experimental hydro pulse discharge (HPD) laboratory setup in order to transfer the copper contained in them (0.11-0.14 %) into the solution and then partially precipitate it in the process of pulsed electrolysis. Pulp from waste (waste + water 1:1) was poured into the cell, then an acidic medium was adjusted to the value pH = 1.0-3.0 using a mixture of reagents. Under the action of electro-hydro pulse the process of pulsed electrolysis occurs simultaneously. Then the lid was tightly closed and a hydro-pulse discharge (HPD) was performed for 5-20 minutes. Under the action of the discharge, all the metals contained in the pulp went into solution and simultaneously precipitated, except for copper ions, which remained in the solution and partially deposited on the cathode. As a result, after processing the pulp with HPD, 20 solutions with a precipitate were obtained. All solutions and precipitates were studied on a copper content by an atomic absorption spectrometer. The optimal conditions for the extraction of copper into solution, namely, the duration of discharge HPD for 20 minutes at pH = 1 and presence of silicate and phosphate ions, were established. All interfering ions of other metals remain in the sediment, since copper is to the right of other metals in the galvanic series.

Early embryonic development, the period from oocyte maturation until blastocyst formation, is the most critical period of mammalian development. It is well known that in vitro maturation, fertilization, and culture of bovine embryos is highly affected by culture conditions. However, the stage-specific effect of culture environment is poorly understood. Therefore, we aimed to examine the effect of in vitro culture conditions during oocyte maturation and fertilization on the transcriptome profile of the resulting blastocysts. Bovine oocytes were matured in vitro and then either directly transferred to synchronized recipients, fertilized, and cultured in vivo (Vitro_M), or transferred after in vitro fertilization (Vitro_F), or at zygote stage (Vitro_Z) and blastocysts were collected at Day 7 by uterine flushing. For in vivo or in vitro fertilization, the same frozen-thawed commercial bull semen has been used. Complete in vitro (IVP) and in vivo produced blastocysts were used as controls. Gene expression patterns between each blastocyst group and in vivo produced blastocyst group were compared using EmbryoGENE's bovine microarray (EmbryoGENE, Québec, QC, Canada) over six replicates of each group (10 blastocyst/replicate). Microarray data were statistically analysed using the Linear Models for Microarray Data Analysis (LIMMA) package under the R program (The R Project for Statistical Computing, Vienna, Austria). Results showed that, the longer the embryos spent under in vitro conditions, the higher was the number of differentially expressed genes (DEG, fold-change = 2 with adjusted P-value = 0.05) compared with in vivo control group. The Vitro_M group showed the lowest number of DEG (149); in contrast IVP group represented 841, DEG, respectively compared to in vivo control group. Ontological classification of DEG showed that lipid metabolism was the most significant function influenced by in vitro maturation conditions. More than 55% of DEG in the Vitro_M group were involved in the lipid metabolism process and most of them showed down-regulation compared to in vivo control group. On the other hand, Vitro_F and Vitro_Z groups showed nearly similar numbers of DEG (584 and 532, respectively) and the majority of these genes in both groups were involved in cell-death- and cell-cycle-related functions. Pathway analysis revealed that retinoic acid receptor activation pathways were the common ones in the Vitro_M and Vitro_F groups. However, different signalling pathways were commonly dominant in the Vitro_F and Vitro_Z groups. This study provides the transcriptome elasticity of bovine embryos exposed to different environments during maturation, fertilization, and culture periods of development.