Use of antioxidants and time of cold storage: effects over viability parameters and enzymatic levels in semen of rainbow trout (Oncorhynchus mykiss, Walbaum, 1792).

The cold storage of milt implies potentials alterations in its quality because the storage generates as main process, free radicals that produce spermatozoa membrane lipids damage with the consequent motility and fertilising capacity disruptions. To decrease the damage generated by free radicals the cells have antioxidant defences (proteins, enzymes, and low molecular weight substances). The objective of the present study evaluated the time storage effect and different antioxidants prepared in spermatic diluents on sperm viability of O. mykiss milt stored at 4°C. The two-way ANOVA denoted that the time storage and antioxidant influence have significant effects separated or combined on viability parameters (sperm motility and viability, proteins concentrations and superoxide dismutase enzymatic activity in seminal plasma). In contrast, only the storage time affected the fertilising capacity and catalase enzymatic activity in seminal plasma. The resulting analysis can conclude that the antioxidant presence improves the viability of cold stored milt, especially the transport conditions and the antioxidants allow the fecundity despite motility decrease.

Real-Time Sensing of Output Polymer Flow Temperature and Volumetric Flowrate in Fused Filament Fabrication Process

In this paper we addressed key challenges in engineering an instrumentation system for sensing and signal processing for real-time estimation of two main process variables in the Fused-Filament-Fabrication process: (i) temperature of the polymer melt exiting the nozzle using a thermocouple; and (ii) polymer flowrate using extrusion width measurements in real-time, in-situ, using a microscope camera. We used a design of experiments approach to develop response surface models for two materials that enable accurate estimation of the polymer exit temperature as a function of polymer flowrate and liquefier temperature with a fit of 𝑅2=99.96% and 99.39%. The live video stream of the deposition process was used to compute the flowrate based on a road geometry model. Specifically, a robust extrusion width recognizer algorithm was developed to identify edges of the deposited road and for real-time computation of extrusion width, which was found to be robust to filament colors and materials. The extrusion width measurement was found to be within 0.08 mm of caliper measurements with an 𝑅2 value of 99.91% and was found to closely track the requested flowrate from the slicer. This opens new avenues for advancing the engineering science for process monitoring and control of FFF.

A Model of Catalytic Cracking: Catalyst Deactivation Induced by Feedstock and Process Variables

Changes in the quality of the feedstocks generated by involving various petroleum fractions in catalytic cracking significantly affect catalyst deactivation, which stems from coke formed on the catalyst surface. By conducting experimental studies on feedstocks and catalysts, as well as using industrial data, we studied how the content of saturates, aromatics and resins (SAR) in feedstock and the main process variables, including temperature, consumptions of the feedstock, catalyst and slops, influence the formation of catalytic coke. We also determined catalyst deactivation patterns using TG-DTA, N2 adsorption and TPD, which were further used as a basis for a kinetic model of catalytic cracking. This model helps predict the changes in reactions rates caused by coke formation and, also, evaluates quantitatively how group characteristics of the feedstock, the catalyst-to-oil ratio and slop flow influence the coke content on the catalyst and the degree of catalyst deactivation. We defined that a total loss of acidity changes from 8.6 to 30.4 wt% for spent catalysts, and this depends on SAR content in feedstock and process variables. The results show that despite enriching the feedstock by saturates, the highest coke yields (4.6–5.2 wt%) may be produced due to the high content of resins (2.1–3.5 wt%).

Comprehensive Identification and Profiling of miRNAs Involved in Terpenoid Synthesis of Gleditsia sinensis Lam.

Gleditsia sinensis Lam. is a tree with worldwide distribution and important economic and medicinal values; its pods contain terpenoids including gleditsioside, thiamine, and brassinosteroids. However, thus far, there are few studies on the terpenoid regulation of G. sinensis at the molecular level. microRNA (miRNA) is a class of small RNAs with conserved and crucial roles in the regulation of diverse biological processes during plant growth and development. To identify the miRNAs of G. sinensis and evaluate their involvement in terpenoid synthesis, this investigation quantified the content changes in saponins in pods at three developmental stages: May (pod-setting stage), July (elongation stage), and September (browning stage), and then we performed genome-wide miRNA profiles during the three development stages of the G. sinensis pods. A total of 351 conserved miRNAs belonging to 216 families were identified, among which 36 conserved miRNAs exist specifically in legumes. Through target analysis, 708 unigenes were predicted to be candidate targets of 37 differentially expressed miRNAs. The targets of miR838-3p and miR2093-5p were involved in the derived branches of monoterpenes and gleditsioside, in brassinosteroid biosynthesis (BRB), and in indole alkaloid biosynthesis (IAB). Intriguingly, the targets of miR829-3p.1 were predicted to take part in thiamine biosynthesis, and the targets of miR4414b and miR5037a were involved in the main process of cytokinin synthesis. The corresponding targets participated in BRB, IAB, and terpenoid backbone biosynthesis, which were enriched significantly, suggesting that miR2093-5p, miR4414b, miR5037a, miR829-3p.1, and miR838-3p play indispensable roles in the regulation of triterpenoid saponin and monoterpenoid biosynthesis. To date, this is the first report of miRNA identification in G. sinensis and miRNA expression profiles at different developmental stages of G. sinensis pods, which provides a basis for further uncovering the molecular regulation of terpenoid synthesis in G. sinensis and new insights into the role of miRNAs in legumes.

Effect of Process Parameters on the Surface Microgeometry of a Ti6Al4V Alloy Manufactured by Laser Powder Bed Fusion: 3D vs. 2D Characterization

The influence of the main process parameters, laser power, point distance and time exposure, on the surface microgeometry of Ti6Al4V specimens produced by a pulsed powder bed fusion process was investigated. A 3D characterization was carried out and collected data were elaborated to reconstruct the surface and to determine both the 3D and the 2D material ratio curves along different directions. The 3D material ratio curve gives a slightly lower material ratio of peak zone Mr1 and higher material ratio of valley zone Mr2, reduced peak height Rpk and reduced valley height Rvk than the 2D curves. Roughness is greater in the 3D analysis than in the 2D one, skewness is the same and kurtosis increases from <3 in 2D to >3 in 3D. Roughness and skewness increase on increasing point distance and decreasing time exposure and laser power. Within the investigated ranges (27.3–71.2 J/mm3), an increase in energy density reduces the surface roughness while skewness and kurtosis are not significantly affected. The results indicate that a 3D approach allows better characterization of the surface microgeometry than a 2D one.

The ISO/IEC 29110 Software Lifecycle Standard for Very Small Companies

For many small and start-up software companies, implementing controls and structures to properly manage their software development activity is a major challenge. It is commonly agreed that very small software companies, implementing management procedures, and controls to appropriately administer their software development activity is a significant challenge. To help meet the need for VSE-specific systems and software lifecycle profiles and guidelines, the ISO/IEC jointly published ISO/IEC 29110 “Lifecycle profiles for Very Small Entities” series of standards and guides, with the overall objective being to assist and encourage very small software organization in assessing and improving their software. The purpose of this chapter is to provide a primer on the ISO/IEC 29110 standard focusing on two main process areas of Project Management and Software Implementation.

The The Effect of Concentration of Citric Acid Solution on Extraction of Pectin from Watermelon Albedo

Watermelon albedo or the white flesh of watermelon rind contains pectin with high enough content. In this study was conducted the extraction of pectin from watermelon albedo by the liquid-solid extraction method. The citric acid solution was used as a solvent with concentrations varied by 4%, 7%, and 10%. The research steps include the pretreatment of raw material, the extraction, the posttreatment of extraction, and the analysis of pectin. The pretreatment aimed to reduce water content and reduce the size of raw material. The extraction process was the main process in which pectin dissolution occurred in the citric acid solvent. Furthermore, the posttreatment of extraction aimed to obtain pectin solid with the addition of ethanol. The final step was the analysis, including pectin yield, moisture content, methoxyl content, galacturonic acid content, and pectin functional group. Based on research obtained, an increase in the concentration of citric acid increased pectin yield, methoxyl content, and galacturonic acid content. The moisture content of pectin decreased with the increasing concentration of citric acid. Pectin yield, moisture content, methoxyl content, galacturonic acid content resulted from 10% concentration of citric acid solvent are 8.356%, 19.748%, 7.029%, and 69.048%, respectively. Based on FTIR analysis, the functional groups contained in pectin are hydroxyl group, methyl group, carbonyl group, and ether group. This functional groups are main constituents of pectin structure.

Removal of Mefenamic Acid from Aqueous Solution by Fenton Process: Optimization Using Response Surface Methodology with Central Composite Design

In the present study, the three main process parameters in the Fenton process for the removal of pharmaceutical compound Mefenamic acid from an aqueous solution were optimized using response surface methodology (RSM). Central composite design (CCD) was used for process optimization. The primary and secondary interaction effects of the selected parameters such as H2O2, Fe2+ and pH on the removal of mefenamic acid were examined. A mathematical model for the removal process based on the selected variables was developed. The interaction effect between the chosen parameters shows that the removal of mefenamic acid was enhanced in the acidic pH range at a high concentration of H2O2 and in a medium concentration level of the catalyst Fe2+. The removal efficiency of 81.24% was obtained for mefenamic acid at the optimized condition of variables such as 9.36 mM H2O2, 0.058 mM Fe2+and at a pH value of 2.1.

Study of Radiation Embitterment and Degradation Processes of Li2ZrO3 Ceramic under Irradiation with Swift Heavy Ions

The work is devoted to the study of radiation damage and subsequent swelling processes of the surface layer of Li2ZrO3 ceramics under irradiation with heavy Xe22+ ions, depending on the accumulation of the radiation dose. The samples under study were obtained using a mechanochemical synthesis method. The samples were irradiated with heavy Xe22+ ions with an energy of 230 MeV at irradiation fluences of 1011–1016 ion/cm2. The choice of ion types is due to the possibility of simulating the radiation damage accumulation processes as a result of the implantation of Xe22+ ions and subsequent atomic displacements. It was found that, at irradiation doses above 5 × 1014 ion/cm2, point defects accumulate, which leads to a disordering of the surface layer and a subsequent decrease in the strength and hardness of ceramics. At the same time, the main process influencing the decrease in resistance to radiation damage is the crystal structure swelling as a result of the accumulation of defects and disordering of the crystal lattice.

EFFECT OF WATER-SOLUBLE POLYMER NV-1A ON ELECTROCHEMICAL PARAMETERS OF SULFUR ELECTRODE

Studies have shown the possibility of a long cycle of sulfur electrode with a high content of active material. The use of water-soluble binder material NV-1A leads to the realization of high current loads in the Li-S battery. Impedance spectroscopy has shown that the low coulombic efficiency in the cycling of the sulfur electrode is primarily due to the spontaneous dissolution of sulfur in the electrolyte, which requires high energy consumption when charging the Li-S battery. The reduction of the specific capacity during cycling is associated with the formation and accumulation of non-conductive films of short-chain polysulfides. On the basis of the conducted researches and the review of the literature sources ways of overcoming of this problem are offered. The ability of cycling the sulfur electrodes at the high current loads has been shown. The discharge capacity values of the sulfur electrodes at the current load 790 mA∙cm-2 are 500 і 420 mAh∙g-1 on the 5-th and 100-th cycles, accordingly. Using the method of impedance spectroscopy, it has been supposed that the formation and accumulation of unconductive Li2S2 / Li2S phases is the main process, which induce the quick capacity reduction of Li - S batteries upon cycling.