Bacterial Cellulose (BC) and BC Composites: Production and Properties

The synthesis of bacterial cellulose (BC) by Komagataeibacter xylinus strain B-12068 was investigated on various C-substrates, under submerged conditions with stirring and in static surface cultures. We implemented the synthesis of BC on glycerol, glucose, beet molasses, sprat oil, and a mixture of glucose with sunflower oil. The most productive process was obtained during the production of inoculum in submerged culture and subsequent growth of large BC films (up to 0.2 m2 and more) in a static surface culture. The highest productivity of the BC synthesis process was obtained with the growth of bacteria on molasses and glycerol, 1.20 and 1.45 g/L per day, respectively. We obtained BC composites with silver nanoparticles (BC/AgNPs) and antibacterial drugs (chlorhexidine, baneocin, cefotaxime, and doripenem), and investigated the structure, physicochemical, and mechanical properties of composites. The disc-diffusion method showed pronounced antibacterial activity of BC composites against E. coli ATCC 25922 and S. aureus ATCC 25923.

Tomate (Solanum lycopersicum) production and bacterial canker management during COVID-19

<p>The tomato (<em>Solanum lycopersicum</em>) is part of the food basket of Mexicans and is the most consumed vegetable worldwide. Mexico is one of the main producer and exporter countries, the main market to export is the United States of America. The pandemic caused by the severe acute respiratory syndrome coronavirus (SARS-CoV-2) seriously affected the economy and consequently the production and distribution of basic foods, including tomatoes. This work summarizes the experiences derived from the production, detection and phytosanitary management of <em>Clavibacter</em> <em>michiganensis</em> subsp. <em>michiganensis</em> during the July–December 2020 season in a tomato crop under macro tunnel located in Copándaro, Michoacán, Mexico. Agriculture, as an essential economic activity in the production of basic foods, must remain active as it is an unconfined productive process, with a low risk of contagion, and it’s a necessary activity for the economic support of agricultural workers.</p>

Theoretical and Methodological Bases of a New School Model in Russia: Cultural-Historical Psychology and the Activity Approach as the Foundation of Educational Practice

To overcome the crisis of the modern school institution, it is necessary to qualitatively rethink its foundations and to design fundamentally new approaches to implementing the educational program. The theoretical and methodological bases of the concept of a new type of school as a development practice, based on the provisions of Russian cultural-historical psychology and the activity approach are presented. The purpose of the work is to consider in the modern context the key theoretical provisions of Russian psychology and to formulate the methodological principles arising from them, which set the conditions for organizing the educational process, thus ensuring the transition from theory to practice. The key concepts of the school model are development, agency and collaboration: infinite development is formulated as the supreme goal and value of the school, the development of the position of agency is considered as the main productive process, and collaboration is the main professional principle. Eight basic principles are formulated as follows: intent - implementation - reflection as a methodological scheme for organizing school processes, the principle of multidimensional development, the principle of equal importance of school activities, the principle of congruence, the principle of organizing the educational space as a space for growing up, the principle of fellowship of practices and the development-oriented approach to evaluation. Thus, the article presents the authors view of the school as a scientifically grounded anthropological practice. The implementation of the concept, which has already begun in Russia, is an experiment that will make it possible to verify these theoretical and methodological provisions.

Politization in Labor Conflict: Analyzing the Demands of Post-Authoritarian Chilean Strikes

By examining the demands of labor strikes in the private sector, this article claims that Chilean trade unions have experienced a politization process from the transition to democracy to our days (1990–2019). Assuming a Marxist perspective on the labor process, we propose operationalizing politization into three levels based on the nature of demands: (1) remunerative, (2) related to work conditions, and (3) related to the organization of the labor process. The study regards these three levels as a latent variable ranging from less to more control over the productive process, but, also, as a continuum ranging from more legal demands to more illegal demands according to Chilean labor regulation. The results show an increase of politized demands (i.e. more control and less legality) through the years. This case study sheds light on the consequences of a rigid and ineffective regulation and on the necessity to rethink politics in the workplace.

Greening Factor Framework Integrating Sustainability, Green Supply Chain Management, and Circular Economy: The Chilean Case

This paper focuses on two main topics: presenting a novel framework for assessing the sustainability of a productive process and the application of the framework to the specific case of Chile. The proposed framework integrates green supply chain management and circular economy within the sustainability perspective as drivers for improvements in sustainable development. Within the framework, the greening factor is introduced as a new concept that measures the required effort for a productive process to become sustainable. On one hand, the framework aims at computing the greening factor based on the impacts of resources exploitation and products generation. Additionally, the greening factor computation was designed based on qualitative and quantitative analysis of economic, social, and environmental mainstays. On the other hand, this paper presents a general application of the framework on the five biggest Chilean industries, i.e., mining, wine, forest, agriculture, and aquaculture. Based on the presented generalized application, it is possible to foresee the potentiality of Chile becoming a green country in spite of its productive matrix being mainly based on primary industries.

Prospects for the peat using as the basis of the soil-like substrate in mini-ecosystems modelling

Global urbanization is causing a constant decline in arable land as cities and associated industrial zones are “attacking” adjacent agricultural areas. One of the promising ways to solve the problem of increasing food production for the constantly growing population of the planet against the background of rapidly decreasing land resources is the development of fundamentally new alternative methods for the production of crop products, including in greenhouses. The fundamental basis for technological optimization of plant cultivation parameters and the output of the productive process of a particular crop to the maximum of its genetic capacities can be the development of artificial mini-ecosystems based on the reproduction of nature-like processes, implying the balance and combination in one volume of the processes of plant production and reduction of organic waste, initiated directly in the zone of the rhizosphere of plants due to the introduction of technological earthworms into the reduction zone. According to the results of model studies presented in this article, peat is an acceptable basis for the substrate of the root block of a mini-ecosystem, and the introduction of earthworms Eisenia fetida Sav. into the reduction zone does not have a negative effect on lettuce plants, provided that it is used as an energy substrate for cattle manure worms in quantities not exceeding 10 - 20% of the total volume of the substrate.

Ultrasound-Assisted Extraction of Carotenoids from Carrot Pomace and Their Optimization through Response Surface Methodology

Ultrasound-assisted extraction (UAE) was used to extract carotenoids from the carrot pomace. To investigate the effect of independent variables on the UAE, the response surface methodology (RSM) with central-composite design (CCD) was employed. The study was conducted with three independent variables including extraction time (min), temperature (°C), and ethanol concentration (%). The results showed that the optimal conditions for UAE were achieved with an extraction time of 17 min, temperature of 32 °C, and ethanol concentration of 51% of total carotenoids (31.82 ± 0.55); extraction time of 16 min, temperature of 29 °C, and ethanol concentration of 59% for a combination of β-carotene (14.89 ± 0.40), lutein (5.77 ± 0.19), and lycopene (2.65 ± 0.12). The non-significant (p > 0.05) correlation under optimal extraction conditions between predicted and experimental values suggested that UAE is the more productive process than conventional techniques for the extraction of carotenoids from the carrot pomace.

Mycobacterium bovis detection in slaughtered pigs in the state of Rio Grande do Sul, Brazil

The infection by the Mycobacterium genus is important in pig farming due to the economic losses caused by total or partial carcass condemnation in slaughterhouses. The present study investigated the occurrence of a tuberculosis outbreak in pigs, based on the identification of lesions at the slaughter line of a slaughterhouse. At the inspection line of the slaughterhouse, carcasses were identified with viscera containing macroscopic lesions that indicated tuberculosis (granulomatous lymphadenitis). Tracheobronchial, mesenteric, and submandibular lymph nodes were collected, as well as liver samples and their corresponding lymph nodes. The samples were sent to the Federal Agricultural Defense Laboratory (LFDA/RS) and processed for the diagnosis of tuberculosis and the molecular characterization of Mycobacterium bovis. Based on the results of post-mortem and laboratory inspections, the occurrence was characterized as a tuberculosis outbreak in pigs, which originated from a farm in the state of Rio Grande do Sul, Brazil. Over three months, three batches, adding up to 2884 animals, were sent to slaughter, of which 102 (3.5%) had tuberculosis-like lesions at the inspection line. Based on these results, the productive process was investigated, assessing the feeding, water supply, and milk whey offered in the diet of pigs. It was concluded that the outbreak was caused by feeding unpasteurized or inadequately pasteurized (insufficient time x temperature relation) whey to the pigs. The use of whey from cheese production is a frequent practice in the state of Rio Grande do Sul and one of the risk factors for granulomatous lymphadenitis in pigs.

Analysis of measurement uncertainty sources in the casting process

The concepts used in metrology are increasingly part of the productive process of metallurgical companies, considering the globalization of the world market. The interpretation of metrological concepts and their application in decision-making is still a challenge for the industry, especially for the measurement uncertainty calculation. Industries in the casting area are in great need of skilled labor both in relation to the productive process and engineering, as well as in metrology, highlighting the interdisciplinary of the concepts studied in the technical or baccalaureate courses. Therefore, the main objective of this work is to perform a brief literature review of publications made using the value of uncertainty of measurement within the production process of foundries. The results show that there is a potential research in the field, to which it relates the values of measurement uncertainty and fused components.