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Spouted beds are extensively used in different industries. The minimum spouting velocity is a critical hydrodynamic parameter needed for the design and scale-up of these systems. This study deals with an ensemble method involving Multi-Layer Perceptron (MLP) network, the Adaptive Neuro-fuzzy Inference System (ANFIS), the Gaussian Process Regression (GPR), and a Regression Tree (RT) model for predicting minimum spouting velocity for coarse particles in conical spouted beds equipped with nonporous draft tubes (CSBDTs) and conical-cylindrical spouted beds. Some dimensionless variables related to the physical properties of the conical bed and particles' material were constructed and used as model inputs. The proposed method was validated against the measured data. The results revealed that the ensemble method was capable of predicting the minimum spouting velocity with an average absolute relative error (AARE) of 10.52% and 10.35% for the testing data points in the case of CSBDTs and conventional spouted beds, respectively. It was also shown that the proposed ensemble method provided the best results in comparison with the other methods. Therefore, the ensemble method is a useful and powerful technique for predicting the minimum spouting velocity in spouted beds with and without the draft tube. [ABSTRACT FROM AUTHOR]

Introduction: In vitro maturation (IVM) of oocyte is an effective technique for avoiding ovarian hyperstimulation syndrome in patients with polycystic ovaries (PCOS) during in vitro fertilization (1VF). Pervious study indicated that more than 1000 children have been born from IVM technique, especially in patient with PCOS. However, IVM remains questions even today. Epigenetic reprogramming occurs in the periods of gametogenesis and embryogenesis, which regulates the gene activity without alteration of DNA sequences. This review discuss about effects of in vitro maturation (IVM) on epigenetic changes in oocytes and early embryos. Material and methods: This article presents result of a systematic review about effects of in vitro maturation (IVM) on epigenetic changes in oocytes and early embryos. Results: Different studies showed that IVM down regulated the protein expression of enzymes controlling histone acetylation such as histone acetyltransferase GCN5 (GCN5) and histone deacetylase 1 (HDAC1), as well as their common target, acetyl-histone H3 (Ac-H3), in metaphase II (Mil) oocytes and two-cell embryos. The significantly decreased HDAC1 mRNA levels in oocytes and early embryos from IVM strongly suggested that IVM technique down regulated the transcription of HDAC1 gene in oocytes before and after fertilization. Conclusion: Our studies indicated that IVM could affect the protein and gene expression level related to histone acetylation in oocytes and early embryos. Therefore, the impacts of IVM on epigenetic changes may be reasons for the lower rates of fertilization and early embryos in IVM. [ABSTRACT FROM AUTHOR]

Introduction: Impairment of human oocyte maturation during oocyte maturation is a cause of infertility in infertile women. Therefore, oocyte maturation is important in successful reproductive outcome of assisted reproduction technologies (ART). Mitochondria, which are the most organelle in the oocytes, have a critical role during oocyte maturation. Little is known about mitochondrial genomes during oocyte maturation. This study was to identity transcript expression level of mitochondrial transcription factor A (TFAM) gene, by using single-cell real-time PCR during human oocyte maturation. Materials and Methods: 27 consenting women, aged 21-35 years, with male factors infertility were selected for ovarian stimulation and ICSI procedures. The mRNA level of the oocytes identified using single-cell taqman real-time PCR. Results: There was a significant differences the relative expression levels of mitochondrial transcription factor A (TFAM) in stages of metaphase I (MI) and metaphase II (Mil) oocytes as compared to germinal vesicle (GV) stage (p<0.05). Conclusion: Human oocyte maturation is associated with the increased transcript expression level of nuclear (TFAM) encoded gene. Thus, any defect in the transcript expression level of nuclear transcriptional mitochondria (TFAM) gene leads to impaired developmental oocyte competence. [ABSTRACT FROM AUTHOR]