Sistema Regional de Información
en línea para Revistas Científicas de América Latina,
el Caribe, España y Portugal

The present experimental research study was carried out with the purpose of determining the growth, inhibition or destruction of pathogens on days 0 (t0), 7 (t7), 15 (t15) and 30 (t30); by treatment of HHP 400 and 500 MPa, using the method of quantification or counting of cfu colony-forming units, on three different cocktails of bacteria, such as Listeria monocytogenes, Escherichia coli and Salmonella, the microbial contained in the epicarp or peel of the mango fruit was also investigated. The results in this study show that the application of high hydrostatic pressures, with a treatment of 400 MPa of pressure 8 min of duration, managed to eliminate a load of 5.16 Log, cfu count / gr of the day t0, under conditions of 20 ºC of temperature, on sample of Mangifera indica, var. Kent, with a pH of 3.4, on L. monocytogenes under the same conditions was performed in treatment of 500 MPa of pressure with 8 min of time, having a reduction of 4.64 Log, in a t0, HHP treatments was efficient reducing 6 Log, for t7, t15 t30. Similarly, an inactivation of Salmonella was achieved in t0, for HHP 400 MPa 7.74 Log was eliminated, and in 500 MPa 6.84 Log, for a pure culture with a control load of 9.14 Log, it was observed that, in the case of treatments, they do not present bacterial growth, as several authors argue, causing death by cell damage at times t7, t15, t30.  Likewise, E. coli was studied, for t0, there was a reduction in HHP treatments of 400 MPa of 5.64 Log, for HHP 500 a reduction of 5.04 Log, it was observed that in the treatments there was cell damage in t7, t15 and t30 existing a total reduction, it is concluded that in the case of E. coli according to the data obtained there was a total reduction of bacteria. The microflora of the mango skin was studied, it was established that there was a reduction of 3 Log, on average general for treatments of 400 and 500 MPa for times t0, t7, t15 and t30, observing a resistance for both treatments, due to the presence of yeasts.

Water bodies (e.g., rivers, lakes, and reservoirs) are an integral part of the urban environment. The infrastructure of the city affects their condition, in particular, pollution, including heat, which can lead to an increase in phyto- and zooplankton, including blue-green algae, and the appearance of toxins in the water. Identification of places where warm water is discharged into reservoirs is an urgent task. One of the methods of solving this problem is the monitoring of reservoirs from space. Thus, with the help of infrared satellite images, thermal anomalies are visible. In the work, we studied Lake Kenon located in the city of Chita. The satellite images were obtained from the Lansat-8. The channels used were 10 and 11, with a resolution of 60 meters. We revealed that (1) the optimal time for detecting thermal anomalies is the time before freezing in calm weather; (2) the cause of the thermal anomaly of this reservoir is a thermal power plant; (3) analysis of the last 5 years has shown that the water area with an increased surface temperature of the reservoir does not change; (4) the temperature gradient between cold and warm areas is 5°C; (5) the area of the heat spot does not exceed 10% of the total area of the lake. The above conclusions were confirmed using field measurements.

The isolation of soil bacteria from various environments with exceptionally high fertility rates represents an opportunity to identify promising agents to promote agriculture production. The paper aims to study the densities of cultivable bacteria and isolate bacteria from the radish and spring wheat rhizosphere. Plants were grown in the pot experiment with virgin Chernevaya soil, which possessed extraordinary productivity, and zonal forest soil that did not demonstrate similar features. Fifty-nine bacterial isolates were purified and evaluated for their beneficial effects on the early growth of wheat. Isolates belonged to Proteobacteria, Actinobacteria, and Firmicutes phyla, and the most represented genera were Pseudomonas, Streptomyces, Paenibacillus, and Methylobacterium. These dominant bacteria were used in plant inoculation studies. Strains promoted a significant increase in shoot and root length and biomass, thus they may be considered plant growth-promoting rhizobacteria [PGPR]. Regarding biotest assays, strains that displayed high plant growth-promoting capabilities [PGP] were selected for further investigation. This study contributed to bacteria isolates from a unique natural environment with biotechnological potentials in improving plant growth and showed potency to be exploited as bioinoculants.

Climate stabilization and replacement of oil with alternative energy sources are urgent problems in the modern world. Space solar power plants [SSPP] can solve these problems simultaneously. Based on the review of literary sources, we raised one of the primary issues of the SSPP creation related to the need to identify the nature and the extent of its impact on the environment. First, we analyzed the environmental impact of the SSPP and traditional energy sources (thermal power plants, nuclear power plants, and hydroelectric power plants). Second, we considered the environmental impact of various wireless transmission methods of energy from the SSPP: ultrahigh-frequency (microwave) and infrared [IR] laser radiation, and the efficiency of energy transmission from the SSPP. One should emphasize the specific concept of efficiency for these power plants since they have an infinite energy source in the form of the Sun. Thus, the superiority of space solar power plants lies in the absence of nuclear radiation and chemical toxicity, a much higher efficiency, locality of impact (a site with a diameter of 40–50 m on Earth when broadcasting from a geostationary orbit), and a lower cost. For several reasons, mainly due to the terrorist threat, it is advisable to abandon the use of tethered balloons for receiving laser radiation above the clouds to eliminate losses in the atmosphere and carry out a live broadcast and reception of energy on the Earth, creating lasers operating in the windows of atmospheric transparency. One can use local illumination of the atmosphere during the operation of these power plants. The use of laser SSPP is especially relevant for solving the problems of the Arctic and continental shelf development with an extreme climate (taiga and tundra with swamps and permafrost) and for mobile objects and transport.

The introduction of such plasticizers as tributyl phosphate and di-(2-Ethylhexyl)-sebacate [DEHS] into the composition of polyurethane elastomers, synthesized through the stage of epoxyurethane oligomer can significantly reduce the glass transition temperature, which expands the operating temperature range. The peculiarities of changes in the basic properties of the studied elastomers during plasticization are determined by their two-phase structure, which is characterized by hard urethane hydroxyl blocks.

In Nicaragua, studies of the western Malacofauna are relatively few, mainly for the Gastropoda subclass, having as the only references within the country studies carried out by MARENA, COMAP, USAID and FUNCOD in 2002, in which they identified about 106 species among flora and fauna, in which some bivalves are mentioned, on the other hand Santana Aguilar in 2006, identified 70 species of bivalves and 92 gastropods in the Cosigüina Natural Reserve, last but not least the books compiled by López and Urcuyo in 2008 , who make a record of the main characteristics of both subclasses, dividing the information into two volumes, one for each one, giving a photographic record at the end of each taking of the most common bivalve and gastropod species in the Pacific. However, these studies do not take a specific record of the coastal part of León, which presents a diversity of species of both subclasses and that are of great commercial interest for the community, since it is their source of economic income, therefore, The initiative arises to carry out this study on Santa Lucia Island, which is considered a buffer zone of the Juan Venado Nature Reserve, sharing species of both flora and fauna. The study was carried out in the months of September to November, after the end of the closed period of the Bivalvia subclass, taking samplings every 20 days, taking as a reference the northeast coastline of Santa Lucia Island, the coves of "El Rosario" and “El Gancho” (which are characterized by presenting the largest bivalve station and some gastropods, according to locals), a total of 360 specimens were captured, of which the presence of 19 species was identified in sizes from 1 centimeter to 22.9 centimeters, predominating in the case of the bivalves the genus Anadara sp., Of the subclass of the gastropods, the species of Rhinocoryne homboltdti, followed by Cerithidae sp., And Ilichione subrugosa, with the coastal zone presenting the greatest diversity of species of the gastropod subclass In comparison to the coves, however, the coves presented a greater dominance of species of the Bivalvia subclass.

The paper describes the design of an electroosmotic device for treating dehydration of water-mineral-organic wastewater sludge from paper production and a methodology for conducting experimental studies. As for regression equations for the reduction factor of the waste mass, specific indicators were presented: drainage fluid consumption, current strength, power consumption, and energy, depending on the voltage on the electrodes and the duration of treatment. Besides, the required waste treatment function depends on the voltage and the required waste concentration. Equations and graphs were presented. In terms of the intensity of fluid excretion, it was found that the most effective treatment is performed during the first 0.5–0.7 h. At a voltage of about 25 V, the processing time of waste (until the mass of waste is reduced to 1/3) is about 0.75 h, and at a voltage of less than 10 V, it is about 3–5 h. With a decrease in the voltage, the liquid withdrawal slows down faster. By the magnitude of the current, the separation process lasts for the first 0.7–1.0 h. By the nature of the change in the current, the process is homogeneous (differing only in intensity) at a voltage of more than 8 V. At a lower voltage, the intensity of waste separation by current strength and an increase in the duration of processing decreases sharply. The power consumption is actively growing in the first 1–2 h of processing, gradually slowing down. Then we found the proportionality of power to the applied voltage. The increase in power was associated with a decrease in the distance between the electrodes. With a decrease in the mass of waste less than 50% of the initial value, energy is less efficiently used for separating waste, and the observed increase in energy consumption during further processing sharply increases energy consumption. To reduce the final mass of waste and obtain their concentrate, it was necessary to increase energy consumption. Waste processing should be stopped when 1/3 of the initial waste mass remains due to the actual cessation of the separation of waste fractions with an active increase in energy consumption.

The Project Management Information System (PMIS) is a powerful tool in project management discussions due to its many benefits. Improper deployment of a PMIS and disregard for its qualitative factors influencing project success will never lead to the achievement of project goals. The purpose of this study was to investigate the impact of using PMIS on the cost management of construction projects that have used this information system. In this study, the impact of PMIS quality factors such as project quality, level of implementation technology, level of design skills, teamwork coefficient and execution time on project cost management was evaluated. The statistical population is the questionnaire of projects implemented through PMIS in construction projects, based on which 100 questionnaires were distributed among the projects and then collected. In this study, structural equation modeling has been used to investigate the research hypotheses. In this regard, "SPSS" software was used. The results of this study indicate that system quality, information quality and service quality have a positive effect on project success in terms of cost management.

In this paper, to determine the main knowledge streams of technological learning in joint R&D (JRD) projects in petroleum industry, the co- word analysis method is used. The knowledge map is drawn by reviewing 388 papers published in the study area from 2000 to 2021 in Scopus and Sage databases using VOSviewer1.6.16 software. Accordingly, by reviewing the existing knowledge, the two main concepts of knowledge management and technological innovation are identified. Then, using text mining method and drawing a concept knowledge map, 8 clusters are extracted and their relationships are analyzed using Netdraw software.  Finally, the study period from 2000 to 2021 is divided into three main categories: organizational - communication characteristics, economic goals and concepts of innovation, and shown the most focus in recent years is in the field of innovation concepts.

Controlling the moisture level is especially important when irrigating various crops to obtain a resistant, stable harvest and save water resources. Over moistening of the soil adversely affects the soil structure and can lead to salinization, waterlogging, and acidification. In addition, the formation of surface water runoff from the fields causes depletion of nutrients, oxygen starvation, and, ultimately, soil degradation. The degradation of fields (areas of the field) leads to the withdrawal of the field from crop rotation (exploitation), a reduction in acreage, the need for agrotechnical measures, reclamation, and, as a result, high financial costs. Currently applied irrigation technologies lead to the withdrawal of up to 50% of irrigated land. Therefore, the technology of differentiated irrigation with constant control over the condition of the soil and plants will help eliminate these negative consequences while increasing the yield and reducing the consumption of water, electricity, and labor costs. For the implementation of this technology, sensors are needed to control the moisture and temperature of the soil at different depths and perform operational control of the water supply to the field. The implementation of a constant connection between the field and the plant with the water supply system will allow creating digital irrigation map and forming of a database about the irrigated field underlying the information and created advisory system. The system for the continuous monitoring of soil moisture and temperature at different depths is based on IT technology with data transmission via radio communication channels. It uses platforms for data transmission via such communication channels as LoRaWAN (highly economical wireless communication interface from ICBCom), GSM (Groupe Spécial Mobile - the global standard for digital mobile cellular communication), and the Internet.