Innovative engineering training in a competitive educational environment

Introduction. The level of mastery of innovative engineering has always determined the qualifications of engineering personnel, who ensure the technological progress of society and the modern technological structure of its economy. In this regard, the problem of increasing the efficiency of preparation for such activities is relevant. To solve it, an appropriate educational environment is created. This educational environment involves a teaching, developmental, upbringing, control-diagnostic and reflective means, which allows various pedagogical conditions, including innovative activities, to be simulated. The most effective of them are competitive environments, due to the increased motivation of their subjects for learning, formed when the natural quality of a person, i.e. competitiveness, is developed in them. However, these environments do not fully disclose the mechanism of formation of motivation and its structure. This raises the dilemma of creating a new competitive educational environment based on the use of competitiveness.The aim of the present research is to increase the efficiency of university students' training for innovative engineering activities due to high motivation to master it through the use of competitiveness.Methodology and research methods. In the current research, the authors were guided by the concept of multi-level and multi-stage preparation of university students for innovative engineering activities. For its implementation, a methodological system was used, including: 1) approaches to learning (integrated, interdisciplinary, systemic, substrate and structured), aimed at creating a competitive educational environment with its specific hierarchy, structure and substrates; 2) methods (competitions - to provide increased motivation; hypothetical-deductive method - to put forward a hypothesis; morphology - to analyse and choose methods; pedagogy of cooperation - to create a comfortable environment); 3) principles (competitiveness, unity of fundamental and professional orientation, interdisciplinarity and interdisciplinarity, etc.).Results and scientific novelty. In the course of the research, a competitive educational environment was created as a system of interacting subjects and objects of educational activity, which has a multicomponent structure. During its developmental process, special attention was paid to the design of models of organisational forms of its implementation, common to which is the high personal motivation of the participants due to the presence of competition, competitive spirit and rivalry. One of them is the All-Russian Scientific Student Festival and related events, annually organised by the authors. The features of increased motivation formation to master innovative activities in these conditions among students, taking into account their psychological and behavioural characteristics, were considered as well. Its structure was revealed as a set of motives, which encourage the individual to be involved in a particular activity. The motives are determined not only by the ability to realise the student's personal quality of competitiveness, but also by other motives caused by emotions they experience at the stages of the competitive substrate of the festival (preparation - performance - analysis). This constitutes the scientific novelty of the research conducted by the authors.Practical significance. The methodological system of research is concretised. The methods have been created for organising and holding the festival, teaching innovative engineering activities in a competitive educational environment based on the involvement of students in all stages of innovative activities and increased motivation to master it. Methodological support for the functioning of the educational environment has been developed.

Trypanosoma cruzi synthesizes proline via a Δ1-pyrroline-5-carboxylate reductase whose activity is fine-tuned by NADPH cytosolic pools

In Trypanosoma cruzi, the etiological agent of Chagas disease, the amino acid proline participates in processes related to T. cruzi survival and infection, such as ATP production, cell differentiation, host-cell invasion, and in protection against osmotic, nutritional, and thermal stresses and oxidative imbalance. However, little is known about proline biosynthesis in this parasite. Δ1-Pyrroline-5-carboxylate reductase (P5CR, EC 1.5.1.2) catalyzes the biosynthesis of proline from Δ1-pyrroline-5-carboxylate (P5C) with concomitant NADPH oxidation. Herein, we show that unlike other eukaryotes, T. cruzi biosynthesizes proline from P5C, which is produced exclusively from glutamate. We found that TcP5CR is an NADPH-dependent cytosolic enzyme with a Kmapp for P5C of 27.7 μM and with a higher expression in the insect-resident form of the parasite. High concentrations of the co-substrate NADPH partially inhibited TcP5CR activity, prompting us to analyze multiple kinetic inhibition models. The model that best explained the obtained data included a non-competitive substrate inhibition mechanism (Kiapp=45±0.7μM). Therefore, TcP5CR is a candidate as a regulatory factor of this pathway. Finally, we show that P5C can exit trypanosomatid mitochondria in conditions that do not compromise organelle integrity. These observations, together with previously reported results, lead us to propose that in T. cruzi TcP5CR participates in a redox shuttle between the mitochondria and the cytoplasm. In this model, cytoplasmic redox equivalents from NADPH pools are transferred to the mitochondria using proline as a reduced metabolite, and shuttling to fuel electrons to the respiratory chain through proline oxidation by its cognate dehydrogenase.

Model kinetika inhibisi substrat pada pertumbuhan Kluyveromyces lactis

Substrat inhibition kinetic model of Kluyveromyces lactis growthFood industry waste such as whey may be utilized as substrates in fermentation processes. Kluyveromyces lactis is yeast that can metabolize the lactose content of whey. In fermentation process design, the kinetics data and growth model of the microorganism are essential. This research was done to identify the growth kinetic model of Kluyveromyces lactis FNCC 3024 in lactose, glucose, and galactose substrates. Substrate concentration was varied as 5, 10, 20, 50, 100, and 150 g/L. Yeast growth profile in glucose and lactose substrates indicated substrate inhibition effect, while the growth profile in galactose substrate did not. Non-competitive substrate inhibition kinetic model was more suitable for glucose and lactose models, with a relatively small sum of squares of errors, namely 9.956 x 10-3 for glucose and 3.777 x 10-3 for lactose. Monod kinetic model for galactose substrate produced the lowest sum of squares of errors, namely 1.358 x 10-3. The maximum specific growth rate obtained from the modeling for glucose, lactose, and galactose substrates were 0.295, 0.265, and 0.147 hour-1.Keywords: kinetics, growth, inhibition, substrate, Kluyveromyces lactis Abstrak Limbah industri makanan seperti whey dapat dimanfaatkan sebagai substrat dalam proses fermentasi. Kluyveromyces lactis adalah salah satu ragi yang dapat memetabolisme kandungan laktosa dari whey. Pada perancangan proses fermentasi sangat diperlukan data kinetika dan model pertumbuhan dari mikroorganisme. Penelitian ini dilakukan untuk mengetahui model kinetika pertumbuhan batch Kluyveromyces lactis FNCC 3024 pada substrat laktosa, glukosa dan galaktosa. Konsentrasi substrat divariasi sebesar 5, 10, 20, 50, 100 dan 150 g/L. Profil pertumbuhan ragi pada substrat glukosa dan laktosa menunjukkan adanya inhibisi substrat sedangkan profil pertumbuhan pada substrat galaktosa inhibisi substrat tidak tampak. Model kinetika inhibisi subtrat non-kompetitif lebih tepat digunakan untuk substrat glukosa dan laktosa dengan kuadrat beda yang cukup kecil yaitu 9,956 x 10-3 untuk glukosa dan 3,777 x 10-3 untuk laktosa. Model kinetika Monod untuk substrat galaktosa memberikan jumlah kuadrat residual terkecil yaitu 1,358 x 10-3. Laju pertumbuhan spesifik maksimum yang dihasilkan dan pemodelan untuk substrat glukosa, laktosa dan galaktosa berturut-turut adalah 0,295, 0,265 dan 0,147 jam-1.Kata kunci : kinetika, pertumbuhan, inhibisi, substrat, Kuyveromyces lactis

Microbial methanogenesis in the sulfate-reducing zone in sediments from Eckernförde Bay, SW Baltic Sea

The presence of surface methanogenesis, located within the sulfate-reducing zone (0–30 centimeters below seafloor, cmbsf), was investigated in sediments of the seasonally hypoxic Eckernförde Bay, southwestern Baltic Sea. Water column parameters like oxygen, temperature and salinity together with porewater geochemistry and benthic methanogenesis rates were determined in the sampling area ''Boknis Eck'' quarterly from March 2013 to September 2014, to investigate the effect of seasonal environmental changes on the rate and distribution of surface methanogenesis and to estimate its potential contribution to benthic methane emissions. The metabolic pathway of methanogenesis in the presence or absence of sulfate reducers and after the addition of a non-competitive substrate was studied in four experimental setups: 1) unaltered sediment batch incubations (net methanogenesis), 2) 14C-bicarbonate labeling experiments (hydrogenotrophic methanogenesis), 3) manipulated experiments with addition of either molybdate (sulfate reducer inhibitor), 2-bromoethane-sulfonate (methanogen inhibitor), or methanol (non-competitive substrate, potential methanogenesis), 4) addition of 13C-labeled methanol (potential methylotrophic methanogenesis). After incubation with methanol in the manipulated experiments, molecular analyses were conducted to identify key functional methanogenic groups. Hydrogenotrophic methanogenesis in sediments below the sulfate-reducing zone (> 30 cmbsf) was determined by 14C-bicarbonate radiotracer incubation in samples collected in September 2013. Surface methanogenesis changed seasonally in the upper 30 cmbsf with rates increasing from March (0.2 nmol cm−3 d−1) to November (1.3 nmol cm−3 d−1) 2013 and March (0.2 nmol cm−3 d−1) to September (0.4 nmol cm−3 d−1) 2014, respectively. Its magnitude and distribution appeared to be controlled by organic matter availability, C / N, temperature, and oxygen in the water column, revealing higher rates in warm, stratified, hypoxic seasons (September/November) compared to colder, oxygenated seasons (March/June) of each year. The majority of surface methanogenesis was likely driven by the usage of non-competitive substrates (e.g., methanol and methylated compounds), to avoid competition with sulfate reducers, as it was indicated by the 1000–3000-fold increase in potential methanogenesis activity observed after methanol addition. Accordingly, competitive hydrogenotrophic methanogenesis increased in the sediment only below the depth of sulfate penetration (> 30 cmbsf). Members of the family Methanosarcinaceae, which are known for methylotrophic methanogenesis, were detected by PCR using Methanosarcinaceae-specific primers and are likely to be responsible for the observed surface methanogenesis. The present study indicated that surface methanogenesis makes an important contribute to the benthic methane budget of Eckernförde Bay sediments as it could directly feed into methane oxidation above the sulfate-methane transition zone.

Heterotrophic nitrification and aerobic denitrification by a novel groundwater origin cold-adapted bacterium at low temperatures

A novel cold-adapted aerobic denitrifyingP. migulaeAN-1 was isolated. Its nitrifying–denitrifying capability was determined. Nitrate removal of the strain was described by Monod kinetics with a non-competitive substrate inhibition and optimized.

Biodegradation Characteristics and Bioaugmentation Potential of an Efficient O-Cresol-Degrading Strain Isolated from Petrochemical Sewage Treatment Plant

O-cresol and its isomers are one of the major pollutants to water environment. In this study, a highly effective o-cresol-degradation strain was isolated from the activated sludge of a petrochemical sewage treatment. Based on its morphology, physiological characteristics and 16S rDNA sequence analysis, it was identified as Pseudomonas sp. The optimal operating temperature, initial pH and rotary shaker speed for the strain to degrade o-cresol were experimentally determined to be 30°C,pH 6.5~8.0 and 150~200 rpm, respectively. Substrate scope experiment showed that the strain can degrade o-cresols other isomers and phenol. The degradation kinetics of the strain can be described by competitive substrate inhibition model with a maximum specific degradation rate of 0.055h-1. Furthermore, the bioaugmentation of the strain in the refinery wastewater to degrade o-cresol was investigated. The result showed that the strain is able to survive in refinery wastewater with high concentration of o-cresol and remove it efficiently.