rss_2.0Life Sciences FeedSciendo RSS Feed for Life Scienceshttps://www.sciendo.com/subject/LFhttps://www.sciendo.comLife Sciences Feedhttps://www.sciendo.com/subjectImages/Life_Sciences.jpg700700Vectors of Efficiency in Hybrid Poplar Genotype Testinghttps://sciendo.com/article/10.2478/sg-2021-0004<abstract> <title style='display:none'>Abstract</title> <p>The Natural Resources Research Institute Hybrid Poplar Program breeds and tests genetically improved clones for bio-mass production and environmental services. The testing process progresses from Nursery Progeny Tests (NPT) to Family Field Trials (FFT) to Clone Trials (CT) to Yield Blocks (YB), with limited replication of many clones in FFT and CT and a limited number of highly selected clones set out in monoclonal blocks (YB) to approximate the conditions of commercial plantations. We used correlation vectors, R<sup>2</sup> (coefficient of determination) and r<sub>s</sub> (Spearman’s Coefficient) for growth (DBH<sup>2</sup>) and McFadden’s Pseudo R<sup>2</sup> for canker severity score, to determine where testing times could be altered (age – age correlations) and whole testing steps eliminated. FFT can be shortened from 5 years to 4 years. In CT, rank correlations between age 5 (half-rotation) and age 9/10 (full rotation) were significant (R<sup>2</sup> = 0.39 – 0.72), but age 5 selection missed 44 % of the top ten clones at age 9/10. Clone rank in CT at full, but not half, rotation was correlated with rank at full rotation in YB. Choosing clones at 9 years in CT adds 4 years but allows possible elimination of YB for clone selection. Both FFT and CT are necessary. Canker abundance and severity in CT at full rotation cannot be determined at earlier ages. An aggressive strategy saves 6 years of testing.</p> </abstract>ARTICLE2021-03-28T00:00:00.000+00:00Genetic structure and postglacial recolonization of Du Tour in the West Siberian Plain, inferred from nuclear microsatellite markershttps://sciendo.com/article/10.2478/sg-2021-0008<abstract> <title style='display:none'>Abstract</title> <p>The total of 257 trees from the ten natural Siberian stone pine populations of West Siberian Plain, Ural Mountains and Kuznetsk Alatau were studied with the eight nuclear microsatellite loci. Differentiation of population groups indicates the possible existence of separate refugia in the past in the Urals and Kuznetsk Alatau. The northern populations of Western Siberia were characterized by a reduced level of genetic diversity, which could be a consequence of the founder effect in the process of <italic>P. sibirica</italic> migration from the southern regions of Western Siberia and the Urals since the end of the last glacial maximum. The genetic variability distribution among populations shows the uneven dynamics of Siberian stone pine migration from the zones of supposed refugia. The map of the proposed ways of Siberian stone pine migration from the zones of possible refugia was constructed, and it is in a good agreement with the results of palynological investigations.</p> </abstract>ARTICLE2021-06-20T00:00:00.000+00:00Investigation of Clonal Structure and Self-incompatibility in Japanese Endemic Snow Camellia ()https://sciendo.com/article/10.2478/sg-2021-0011<abstract> <title style='display:none'>Abstract</title> <p>We investigated the clonal structure, self-incompatibility, and number of seeds per fruit in <italic>Camellia rusticana</italic>, a Japanese endemic species, in comparison to the closely related <italic>C. japonica</italic>. Clonal propagation was more vigorous in <italic>C. rusticana</italic> than in <italic>C. japonica</italic> and the clonal structure of <italic>C. rusticana</italic> varied among populations. <italic>C. rusticana</italic> can maintain genets for extended periods, even in harsh environments such as high-altitude areas with considerable snow accumulation, because even a single surviving genet can propagate clonally. However, sexual reproduction (<italic>i.e.</italic>, reproduction by seed) is advantageous for dispersal to distant suitable habitats. An artificial crossing test revealed high self-incompatibility in <italic>C. rusticana</italic>, as observed in <italic>C. japonica</italic>. In addition, the number of seeds per fruit was lower in <italic>C. rusticana</italic> than in <italic>C. japonica</italic>. Self-incompatibility in <italic>C. rusticana</italic> may play a role in production of high-quality seed, despite low seed production.</p> </abstract>ARTICLE2021-08-23T00:00:00.000+00:00Genetic comparison of planted and natural stands in Russiahttps://sciendo.com/article/10.2478/sg-2021-0001<abstract> <title style='display:none'>Abstract</title> <p>Genetic diversity and the optimal genetic composition are essential for the adaptability and adaptation of tree populations. Artificial regeneration of stands might reduce the genetic diversity and increase family structures if the seeds were collected from a limited number of mother trees. We did a genetic inventory in 12 pedunculate oak stands in Russia using a set of 366 nuclear gene markers (361 SNPs, 5 Indels) in order to look for differences in the genetic composition among natural and artificial stands. Our results did not reveal any systematic differences among both types of stands. However, we found two extreme cases of limited genetic diversity and increased proportion of full-sibs and half-sibs in urban man-made stands. The implications for the forestry and gene conservation programs were discussed.</p> </abstract>ARTICLE2020-12-25T00:00:00.000+00:00Variation and Evolution of Genome Size in Gymnospermshttps://sciendo.com/article/10.2478/sg-2021-0013<abstract> <title style='display:none'>Abstract</title> <p>Gymnosperms show a significantly higher mean (1C=18.16, 1Cx=16.80) and a narrow range (16.89-fold) of genome sizes as compared with angiosperms. Among the 12 families the largest ranges of 1C values is shown by Ephedraceae (4.73-fold) and Cupressaceae (4.45-fold) which are partly due to polyploidy as 1Cx values vary 2.41 and 1.37-fold respectively. In rest of the families which have only diploid taxa the range of 1C values is from 1.18-fold (Cycadaeae) to 4.36-fold (Podocarpaceae). The question is how gymnosperms acquired such big genome sizes despite the rarity of recent instances of polyploidy. A general survey of different families and genera shows that gymnosperms have experienced both increase and decrease in their genome size during evolution. Various genomic components which have accounted for these large genomes have been discussed. The major contributors are the transposable elements particularly LTR-retrotransposons comprising of <italic>Ty3gypsy</italic>, <italic>Ty1copia</italic> and <italic>gymny</italic> superfamilies which are most widespread. The genomes of gymnosperms have been acquiring diverse LTR-RTs in their long evolution in the absence of any efficient mechanism of their elimination. The epigenetic machinery which silences these large tracts of repeat sequences into the stretches of heterochromatin and the adaptive value of these silenced repeat sequences need further investigation.</p> </abstract>ARTICLE2021-09-25T00:00:00.000+00:00The genetic basis of sex determination in provides molecular markers across the genus and indicates convergent evolutionhttps://sciendo.com/article/10.2478/sg-2021-0012<abstract> <title style='display:none'>Abstract</title> <p>Many dioecious angiosperms are trees, which only flower after years of vegetative development and do not usually exhibit marked secondary sexual dimorphism. Nevertheless, if the genetic basis of sex determination is known, the sex of an individual can be determined using molecular markers. Here, we report that in the genus <italic>Populus</italic> sect. Populus an XY system of sex determination, which is found in <italic>P. tremula</italic> and <italic>P. tremuloides</italic>, likely re-evolved from a ZW system present in <italic>P. alba, P. adenopoda</italic> and <italic>P. qiongdaoensis</italic>. Strikingly, this new XY system is mechanistically identical to the older system found in several species of the <italic>Populus</italic> sections Tacamahaca, Aigeiros and Turanga demonstrating a remarkable example of convergent evolution. In both XY systems, male-specific inversely repeated sequences appear to silence the <italic>ARR17</italic> gene, which functions as a sex switch, via small interfering RNAs and DNA methylation. In the ZW system, female-specific copies of <italic>ARR17</italic> appear to regulate dioecy. With this detailed information on the genetic basis of sex determination it was possible to develop molecular markers that can be utilized to determine the sex in seedlings and non-flowering trees of different poplar species. We used the female-specific <italic>ARR17</italic> gene to develop a sex marker for <italic>P. alba</italic> and <italic>P. adenopoda</italic>. For <italic>P. grandidentata</italic>, we employed the male-specific <italic>ARR17</italic> inverted repeat. Finally, we summarize previously described markers for P. <italic>tremula</italic>, <italic>P. tremuloides</italic>, <italic>P. trichocarpa</italic>, <italic>P. deltoides</italic> and <italic>P. nigra</italic>. These markers can be useful for poplar ecologists, geneticists and breeders.</p> </abstract>ARTICLE2021-09-20T00:00:00.000+00:00Cross-transferability-based identification and validation of simple sequence repeat (SSR) markers in oaks of western Himalayashttps://sciendo.com/article/10.2478/sg-2021-0009<abstract> <title style='display:none'>Abstract</title> <p>Cross-amplification is a cost-effective method to extend the applicability of SSR markers to closely related taxa which lack their own sequence information. In the present study, 35 SSR markers developed in four oak species of Europe, North America and Asia were selected and screened in five species of the western Himalayas. Fifteen markers were successfully amplified in <italic>Quercus semecarpifolia</italic>, followed by 11 each in <italic>Q. floribunda</italic> and <italic>Q. leucotrichophora</italic>, 10 in <italic>Q. glauca</italic>, and 9 in <italic>Q. lana-ta</italic>. Except two primer pairs in <italic>Q. semecarpifolia</italic>, all were found to be polymorphic. Most of the positively cross-amplified SSRs were derived from the Asian oak, <italic>Q. mongolica</italic>. The genoty-ping of 10 individuals of each species with positively cross-amplified SSRs displayed varied levels of polymorphism in the five target oak species, viz., QmC00419 was most polymorphic in <italic>Q. floribunda</italic>, QmC00716 in <italic>Q. glauca</italic> and <italic>Q. lanata</italic>, QmC01368 in <italic>Q. leucotrichophora</italic>, and QmC02269 in <italic>Q. semecarpifolia</italic>. Among five oak species, the highest gene diversity was depicted in <italic>Q. lanata</italic> and <italic>Q. semecarpifolia</italic> with expected heterozygosity (He = 0.72), while the minimum was recorded for <italic>Q. leucotrichophora</italic> and <italic>Q. glauca</italic> (He = 0.65). The SSRs validated here provide a valuable resource to carry out further population genetic analysis in oaks of the western Himalayas.</p> </abstract>ARTICLE2021-06-20T00:00:00.000+00:00Polyploidy in Gymnosperms-A Reappraisalhttps://sciendo.com/article/10.2478/sg-2021-0003<abstract> <title style='display:none'>Abstract</title> <p>Recent polyploidy in gymnosperms is unusually scarce being present in only 9.80 % of the 714 taxa studied cytologically. Polyploid forms are represented by sporadic seedlings and individual trees, intraspecific polyploidy in cultivation or in wild and entirely polyploid species and genera. Polyploidy shows a non-random distribution in different genera being mostly prevalent in <italic>Ephedra</italic> and <italic>Juniperus</italic>, besides the classic examples of <italic>Sequoia</italic> and <italic>Fitzroya</italic>. Remarkably, both <italic>Ephedra</italic> and <italic>Juniperus</italic> show adaptive radiation by interspecific hybridization followed by polyploidy while in <italic>Ginkgo</italic> viable polyploid cytotypes are found in cultivation. Induced polyploidy has not provided any tangible results in the past but recent attempts on certain genera of Cupressaceae hold some promise of producing cultivars for horticulture trade. Lastly, various evidences derived from cytological analysis, fossil pollen, guard cells and comparative genomic studies indicating the occurrence of paleopolyploidy have been discussed.</p> </abstract>ARTICLE2021-01-29T00:00:00.000+00:00Towards new seed orchard designs in Germany – A reviewhttps://sciendo.com/article/10.2478/sg-2021-0007<abstract> <title style='display:none'>Abstract</title> <p>New first and 1.5 generation seed orchards are to be created in Germany based on recently assembled breeding populations of <italic>Acer pseudoplatanus</italic>, <italic>Larix</italic> sp., <italic>Picea abies</italic>, <italic>Pinus sylvestris</italic>, <italic>Pseudotsuga menziesii</italic>, and <italic>Quercus</italic> sp. To justify the high expenses in time and cost for orchard establishment and maintenance, planning should make use of consolidated knowledge and experience of both the national and international scientific community. Here, we briefly describe advances in genetic gains achieved through tree breeding, and resume population genetic aspects and design considerations to draw conclusions for clonal composition and spatial design of the new orchards.</p> <p>We conclude that to avoid outbreeding depression separate orchards are required for each breeding zone. The zones are species-specific and defined by ecological and climatic aspects. A minimum of 60-80 clones per orchard is recommended for native tree species with high proportions of natural regeneration in forest practice. This would allow future selective thinning based on estimated breeding values from progeny testing. It would also permit the transfer of seed orchard progenies into a naturally regenerating forest stands without the risk of a genetic bottleneck. Lower clone numbers are appropriate for non-native species and hybrids. It is important to strictly avoid inbreeding depression, achieved by using only one clone per progeny or population, from which the plus trees were selected. Further, the spatial layout should promote random mating by optimizing the neighbourhood of each clone. With all of these considerations taken into account, we expect superior quality traits and at least 10-15 % more volume from the new seed orchards.</p> </abstract>ARTICLE2021-05-08T00:00:00.000+00:00Tree growth and survival over 61 years at the Second International Larch Provenance Test in southeastern Michigan, USAhttps://sciendo.com/article/10.2478/sg-2021-0002<abstract> <title style='display:none'>Abstract</title> <p>Provenance trials remain an important tool for understanding genetic variation in forest trees. Maintaining decades-old experiments is critical for revealing maladaptation of translocated populations to local sites and meaningful divergence in survival and growth. We revisited the Second International Larch Provenance Test in southeastern Michigan, which featuring 24 provenances of European and Japanese larch. We compiled data collected when the plantation was 25, 41, and 61 years from seed to supplement data published at 19 years from seed. Divergence in survival rates first became pronounced at 41 years from seed. Plantation sources of unknown origin and continental Sudeten provenances had the highest rates of survival. High-elevation sources from the southern Alps performed the poorest. Survival differences were likely driven by ice storm damage and severe growing season droughts, both of which occurred at least 1-2 times per decade in southeastern Michigan over the last 60 years. Provenance performance for growth mirrored that of survival, although sources varied more in their survival than in their growth. Growth rate among sources varied over the 43-year sampling period, with intervals of fast growth occurring in several of the overall poor-performing provenances. Diameter was moderately correlated to both elevation and latitude, with inconsistent correlations to climatic variables. Broad geographical variation in provenance performance was also important in explaining variation in growth. Our data corroborate that monitoring of long-term provenance trials could be an important source of information needed to predict and understand how forest species may respond to imminent climate change and may be critical for developing strategies for its mitigation.</p> </abstract>ARTICLE2021-01-27T00:00:00.000+00:00Genome-wide bioinformatics analysis revealed putative substrate specificities of SABATH and MES family members in silver birch ()https://sciendo.com/article/10.2478/sg-2021-0005<abstract> <title style='display:none'>Abstract</title> <p>Plant SABATH family members catalyze the methylation of many hormones, signaling molecules, and floral scent metabolites, including salicylic acid (SA), jasmonic acid (JA), and indol-3 acetic acid (IAA). Demethylation of resulting methyl esters was executed by members of the MES family. Members of both families are significantly involved in plant developmental processes. Here, using different bioinformatics tools, we studied the evolutionary relationship and characterized the putative functions of the family members in silver birch (<italic>Betula pendula</italic>). It is a socio-ecologically important tree species and plays a vital role in reforestation. Ten and twelve members of the SABATH (BpSABATH1-10) and MES (BpMES1-12) family were identified in silver birch, respectively at the gene and enzyme levels. The <italic>BpSABATH</italic> and <italic>BpMES</italic> genes were distributed on seven of fourteen chromosomes, indicating the occurrence of moderate duplication events important for the expansion of both families. Phylogenetic clustering and the gene ontology database suggest, BpSA-BATH8 is involved in the methylation of indole-3-acetic acid (IAA), while BpSABATH5, BpSABATH6, and BpSABATH7 methylate JA to methyl jasmonate (MeJA). BpSABATH9 was alone in the phylogenetic functional group 1 and prefers SA as a substrate to synthesize methyl salicylate (MeSA). Likewise, BpMES5 and BpMES12 are possibly involved in the demethylation of the methyl ester of IAA, while BpMES6, BpMES7, and BpMES8 are responsible for the demethylation of MeJA. BpMES9 clustered with MES and prefers MeSA as a substrate. The current analysis helped to select candidate genes that could be subjected to further molecular breeding of birch varieties adapted to biotic and abiotic stress conditions.</p> </abstract>ARTICLE2021-04-06T00:00:00.000+00:00Identification of hybrid formulae of a few willows () using ovule numbershttps://sciendo.com/article/10.2478/sg-2021-0006<abstract> <title style='display:none'>Abstract</title> <p><italic>Salix</italic> is a genus of considerable taxonomic complexity, and accurate identification of its species and hybrids is not always possible. Quantification of ovules was used in this study to verify the parentage of a few hybrids of <italic>Salix</italic>. It has been shown that ovule numbers in willow hybrids are the mean of the ovule numbers of their parents. The ovule index of a prostrate specimen of <italic>S. ×cottetii</italic> affirmed that this was a hybrid of <italic>S. myrsinifolia</italic> Salisb. and <italic>S. retusa</italic> L., and the ovule index of the ornamental cultivar ‘The Hague’ affirmed that this was a hybrid of <italic>S. caprea</italic> L. and <italic>S. gracilistyla</italic> Miq. Finally, we also examined a confusing group, previously identified in North America as <italic>S. pentandra</italic>. The ovule indexes and other morphological characters indicated that there were four taxa among the studied specimens: <italic>S. pentandra</italic>, <italic>S. ×meyeriana</italic>, <italic>S. serissima</italic> Fernald, and a hybrid of <italic>S. serissima</italic> and <italic>S. fragilis</italic> that has not previously been described. It was concluded that quantification of ovules in willows is a reliable tool that can be used in willow taxonomy, genetics and population studies.</p> </abstract>ARTICLE2021-04-30T00:00:00.000+00:00Fate of forest tree biotechnology facing climate changehttps://sciendo.com/article/10.2478/sg-2021-0010<abstract> <title style='display:none'>Abstract</title> <p>Woody plants have been cultured <italic>in vitro</italic> since the 1930s. After that time much progress has been made in the culture of tissues, organs, cells, and protoplasts in tree species. Tree biotechnology has been making strides in clonal propagation by organogenesis and somatic embryogenesis. These regeneration studies have paved the way for gene transfer in forest trees. Transgenics from a number of forest tree species carrying a variety of recombinant genes that code for herbicide tolerance, pest resistance, lignin modification, increased woody bio-mass, and flowering control have been produced by <italic>Agrobacterium</italic>-mediated and biolistic methods, and some of them are undergoing confined field trials. Although relatively stable transgenic clones have been produced by genetic transformation in trees using organogenesis or somatic embryogenesis, there were also unintended unstable genetic events. In order to overcome the problems of randomness of transgene integration and instability reported in <italic>Agrobacterium</italic>-mediated or biolistically transformed plants, site-specific transgene insertion strategies involving clustered regularly interspaced short palindromic repeats (CRISPR-Cas9) platform offer prospects for precise genome editing in plants. Nevertheless, it is important to monitor phenotypic and genetic stability of clonal material, not just under greenhouse conditions, but also under natural field conditions. Genetically modified poplars have been commercialized in China, and eucalypts and loblolly pine are expected to be released for commercial deployment in USA. Clonal forestry and transgenic forestry have to cope with rapid global climate changes in the future. Climate change is impacting species distributions and is a significant threat to biodiversity. Therefore, it is important to deploy Strategies that will assist the survival and evolution of forest tree species facing rapid climate change. Assisted migration (managed relocation) and biotechnological approaches offer prospects for adaptation of forest trees to climate change.</p> </abstract>ARTICLE2021-08-23T00:00:00.000+00:00Effects of Energy Efficiency Measures in the Beef Cold Chain: A Life Cycle-based Studyhttps://sciendo.com/article/10.2478/rtuect-2021-0025<abstract> <title style='display:none'>Abstract</title> <p>Circular economy and industrial symbiosis represent a production and consumption model involving sharing, lending, reusing, and recycling existing materials and products in the most efficient way to increase sustainability and reduce or eliminate waste. Beef production has a high impact on the environment in different impact categories, especially those activities related to livestock breeding and feeding. In this study, a life cycle assessment and a life cycle cost evaluation are carried out investigating potential energy efficiency measures to promote industrial symbiosis scenarios referring to a proposed baseline scenario. Three main potential measures are evaluated: energy recovery from waste via anaerobic digestion, integration of renewable sources at warehouses, including solar PV panels, and the replacement of auxiliary equipment at the retailer. It was found that energy reconversion of food waste through anaerobic digestion and cogeneration provides the most valuable benefits to the supply chain. From the economic perspective, using a conventional life cycle cost assessment, the energy production from the use of wastes for anaerobic digestion proved to be the best potential option.</p> </abstract>ARTICLE2021-07-05T00:00:00.000+00:00Energy and Thermal Conductivity Assessment of Dimethyl-Ether and its Azeotropic Mixtures as Alternative Low Global Warming Potential Refrigerants in a Refrigeration Systemhttps://sciendo.com/article/10.2478/rtuect-2021-0002<abstract> <title style='display:none'>Abstract</title> <p>Substituting Hydrofluorocarbons with natural refrigerants in domestic refrigerators will significantly reduce the direct contributions of fluorinated gases to global warming which will be of great environmental benefit. In this study, the performances of dimethyl-ether (RE170) and its azeotropic mixtures (R510A and R511A) in a refrigeration system were assessed theoretically and compare with that of conventional refrigerant. The study revealed that the three investigated alternative refrigerants exhibited significantly good heat transfer characteristics, low pressure ratio, high latent heat in the liquid phase which resulted in their high thermal conductivity and Volumetric Cooling Capacity (VCC). The thermal conductivity of the refrigerants reduces while the evaporating temperature rises and the value obtained for RE170 was the highest among the four refrigerants studied. The Coefficient of Performance (COP) for RE170, R510A and R511A were higher than that of R134a by 6.20, 10.06 and 3.02 % respectively while their power consumptions per ton of refrigeration were lower than that of R134a by 6.99, 11.04 and 1.47 % respectively. In conclusion, dimethyl-ether and its azeotropic mixtures performed better than R134a in that they have higher thermal conductivity, refrigerating effect, VCC, COP, lower power consumption per ton of refrigeration and hence, they can be considered as suitable replacements for R134a in domestic refrigerator.</p> </abstract>ARTICLE2021-01-27T00:00:00.000+00:00Examining the Impact of Different Technical and Environmental Parameters on the Performance of Photovoltaic Moduleshttps://sciendo.com/article/10.2478/rtuect-2021-0001<abstract> <title style='display:none'>Abstract</title> <p>This article presents an evaluation of the performance of PV modules with the variation of some technical and environmental parameters: The PV module tilt angle, and the impact of soiling on the power output of PV module, and the transmittance of the PV glass surfaces. The experiments were achieved in Helwan City (Egypt) at the premises of the Faculty of Engineering of Helwan University. For the soiling part, it comprises two experiments: Transmittance of PV glass surfaces, and the power output of PV modules. For the transmittance experiment, it has been achieved using a simplified method, where three PV glass surfaces were placed at three different tilt angles (0°, 15°, and 30°) and left exposed to the outdoor environment without cleaning for a period of 25 days during the summer season. For the experiment concerning the impact of soiling on the power output, a set of PV modules connected in series have been exposed for a period of 75 days to the outdoor environment without cleaning. Finally, for the PV module tilt angle experiment, another set of PV modules have been used for that purpose, where four different tilt angles were experimented: 0°, 15°, 30°, and 45°. The present research recommends that more studies are needed in the same context, taking into consideration correlating the technical and environmental parameters in one single experiment and during different times of the year. This would be helpful in having overarching perspective regarding the electrical performance of PV modules under different circumstances of tilt angles and soiling patterns within the area of Helwan (Egypt).</p> </abstract>ARTICLE2021-01-19T00:00:00.000+00:00Purification of Oil-Containing Waste Using Solar Energyhttps://sciendo.com/article/10.2478/rtuect-2021-0011<abstract> <title style='display:none'>Abstract</title> <p>Significant oil losses in oil-containing wastes and their adverse impact on the region environmental setting bring about the need to develop an oil-containing wastes treatment technology. To tackle this issue, the authors have set an aim of designing a helio device and creating an oil-containing wastes treatment method based on it to extract oil products. Considering a widespread in the composition and properties of potential oil sludge raw materials and their tendency for either formation of stable emulsions or phase separation, we have conducted in-depth modern physical and chemical studies and defined the need to develop a commercial oil-containing wastes purification method. We have designed the device, in which oil product hydrocarbons undergo thermal treatment using solar energy. Following oil-containing wastes purification using solar energy, the particulate load in soil does not exceed 6.65–6.79 % and the absolute molecular weight of hydrocarbons approaches that of bitumen. The developed oil-containing wastes purification method solves an important environmental issue of oil-containing wastes recycling, promotes recovery, and prevents degradation of natural complexes, and reduces soil and water pollution.</p> </abstract>ARTICLE2021-05-12T00:00:00.000+00:00Investigation on Relative Heat Losses and Gains of Heating and Cooling Networkshttps://sciendo.com/article/10.2478/rtuect-2021-0035<abstract> <title style='display:none'>Abstract</title> <p>The integration of district heating (DH) and cooling (DC) in the sustainable energy system of the future requires a significant reduction in operating temperatures. Supply temperatures below 70 °C are required for new 4<sup>th</sup> Generation DH. Main benefits are the use of low exergy heat sources and the reduction of heat losses. The reduction of heat losses is achieved by reducing the driving temperature difference between the medium pipe and the ground. The decrease of the return temperature level is limited by the consumer behaviour and the ground temperature level. As a consequence, the reduction of the supply temperature is accompanied by a reduction of the maximum transmittable heat flow. For energy efficiency and economic reasons, the relative heat losses are therefore an important design value for DH networks. The study proposes an approach to estimate the relative heat losses by using steady-state heat loss models and analyses the values for different DH generations. In particular, due to the rising of the near-surface soil temperature, the relative cold losses are also studied.</p> </abstract>ARTICLE2021-09-04T00:00:00.000+00:00Natural Ventilation Strategy in a Social Housing with Sub-humid Warm Climate Based on Thermal Comforthttps://sciendo.com/article/10.2478/rtuect-2021-0037<abstract> <title style='display:none'>Abstract</title> <p>Natural ventilation was analysed in a low-income dwelling to control open or closed windows according to a dynamic simulation process in sub-humid warm climate. A selective algorithm to control natural ventilation was determined in an annual period per hour with the following findings: a) an algorithm to select open or closed windows was determined, b) comfort hours per year were evidenced with open, closed windows and selective algorithm to operate natural ventilation, and c) the schedule and periods of ventilation control were presented. Meteonorm® data were used on an hourly basis in Design Builder® simulations and the Meteorological System data based on 30 years of measurements were used to determine the comfort range. Conclusions: the potential benefits to be obtained by applying this ventilation strategy with a selective algorithm are observed in sub-humid warm climate.</p> </abstract>ARTICLE2021-09-17T00:00:00.000+00:00Strategic Environmental Assessment of the Territory as a Public Management Instruments for Technological Development. A Case of Ukrainehttps://sciendo.com/article/10.2478/rtuect-2021-0013<abstract> <title style='display:none'>Abstract</title> <p>The study aims to substantiate theoretical and methodological aspects of the use of strategic environmental assessment as an instrument for public regulation of the ecological status of territories. The research methodology is based on using a systematic approach for conducting a strategic environmental assessment of the possibility of environmental problems and threats posed by the implementation of long-term projects and current activities. The development of ecological balance, comparison of the results of normative and exploratory forecasts of the state of the environment become the basis for the formation of goals of strategic environmental management, the appearance of a set of measures for the conservation and restoration of natural resources. Identification of factors influencing the state of the environment is a necessary condition for the prevention of pollution of territories, inefficient use of natural resources, justification of the essential measures of state regulation to ensure the achievement of goals. The practical experience of assessing the achievements in the management of the conditions of the environment is illustrated by the example of regions of Ukraine. The proposed approach to the development of the ecological balance and the methodology of complex assessment of the ecological status of the territory have scientific novelty and contribute to the assessment of the effectiveness of public administration balanced development of the territories.</p> </abstract>ARTICLE2021-06-01T00:00:00.000+00:00en-us-1