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The paper presents an analysis of selected aluminum alloys as structural materials used in production of aircraft parts as well as specification of technological parameters of Al alloys extrusion on a backward press with their effect on mechanical properties, microstructure and quality of the final product. Upsetting tests with backward extrusion complex cross-sectional profile tests were conducted on aluminum alloys 7075, 2024, 2099. Based on the results, specifications of forging in the form of unit stress - effective strain relations were determined using logarithmic deformation index, allowing proper choice of extrusion parameters. The range of temperatures for hot plastic treatment along with range of extrusion rate for the analyzed thin-walled aircraft profiles were determined. Tests were also conducted on the microstructure of Al alloys in the initial state as well as after the extrusion process had been completed. It has been proved that the proper choice of parameters in the case of a specific profile extruded from Aluminum alloys 2024, 7075, 2099, allows the manufacturing of products of complex crosssections and the quality required in aerospace industry. This has been demonstrated on the example of complex cross-sectional profiles using elements of varied wall thickness.

Basing on experimental data, the possibility of consolidating side products of turning, milling and drilling of aluminum alloys into the form and properties of solids metals using low-temperature KoBo extrusion method has been assessed. Research regarding mechanical and structural properties of the final products revealed their total consolidation and proved their compatibility with requirements for products made of bulk billets. Importantly, the chips consolidation process does not require high or even raised temperature, which significantly reduces the unfavorable phenomenon of chips oxidation and its negative influence on the structure and mechanical properties of products. A very good effect of chips compaction has been proved by KoBo method, which has been confirmed by relatively slightly different mechanical properties of the material after recycling compared with the bulk one. Among currently applied techniques of consolidation of dispersed fractions in a solid state (leaving the melting stage out), the KoBo method seems an innovative way of utilizing metallic chips, as it enables a cold deformation process. The paper presents investigations using 2024 and 7075 aluminum alloys chips from manufacturing process, formed into briquettes and deformed under conditions of KoBo extrusion process, which enables to obtain long product by cold forming. The final product characterized by good microstructures, mechanical features and low cost of production. [ABSTRACT FROM AUTHOR]

The global population of older people grows systematically and with age, the physical and cognitive abilities of people decline. The amount of evidence that gardening may provide substantial health benefits and enhance the quality of ageing is increasing. This paper presents a systematic review of the therapeutic effects of horticulture and gardening on clients aged ≥60 years. It encompasses articles published in English between January 1, 2010, and December 31, 2021. The literature survey shows that the interest in the topic has grown significantly in recent years as over half of the published studies are from 2019 to 2021. Most of this work was done in Asia (60%), America, Europe, Australia and New Zealand. The most commonly used interventions were active horticultural therapy programs or gardening, but 20% of the studies explored the passive connection of being outside. The fitness of the elderly was measured using 33 psychological tests, 32 physiological and functional parameters and different kinds of self-developed questionnaires and interviews. The most commonly used psychological tests were the Geriatric Depression Scale, Self-rated Health and Quality of Life, Mini-Mental State Examination, Friendship Scale, Lubben Social Network Scale, and the Attitudes to Ageing Questionnaire. The physiological and functional parameters included heart rate variability, blood pressure, electroencephalography, brain nerve growth factors, and different types of biomarkers. The study outcomes demonstrated positive results of horticultural therapy on human health and well-being, particularly in a psychological dimension and to a smaller but still significant extent physiological aspect.

This study focused on the identification and elimination of endophytic bacterial contaminations during in vitro propagation of European bladdernut (Staphylea pinnata). Axillary shoots were propagated on Murashige and Skoog medium with 20 mg ∙ dm−3 FeEDDHA, 5 μM BA and 0.5 μM NAA at 20/18°C (day/night) and a 16-h photoperiod. Clouding by endophytic bacterial colonies was observed where shoots contacted the media. Bacteria were isolated and separated by repeated streaking as two strains. Gram staining revealed that both strains were Gram-negative. The colonies were very precisely identified as Acinetobacter johnsonii, strain ATCC 17909, and Methylobacterium rhodesianum, strain DSM 5687, using VITEK®2—a rapid bacterial identification system—and the 16S rRNA gene sequencing method. The agar disc-diffusion test proved that both bacterial strains were susceptible to 13 antibiotics (out of 25 tested), derived from the groups of fluoroquinolones, aminoglycosides and tetracyclines. Doxycycline or gentamicin (100–300 mg ∙ dm−3) was added to the S. pinnata shoot propagation medium to eliminate bacteria. Gentamicin 100 mg ∙ dm−3 showed the best effect, inhibiting the growth of endogenous bacteria (63%) when applied in the medium for 4 weeks. After the following transfer to media without antibiotics, shoots developed axillary buds and bacterial colonies were not observed.

The objective of the present study was to compare the effect of rhamnolipids on the microbial biomass content and the activity of dehydrogenases (DHA), acid phosphatase (ACP), alkaline phosphatase (ALP), and urease (URE) in soil contaminated with two types of coal tar creosote: type C and type GX-Plus. The experiment was carried out on samples of sandy clay loam under laboratory conditions. Coal tar creosote was added to soil samples at a dose of 0 and 10 g·kg−1 DM, along with rhamnolipids at a dose of 0, 10, 100, and 1000 mg·kg−1 DM. The humidity of the samples was brought to 60% maximum water holding capacity, and the samples were incubated at 20°C. Microbial and biochemical parameters were determined on days 1, 7, 21, and 63. The obtained results demonstrated that the addition of rhamnolipids did not result in any significant changes in the activity of the determined parameters in the uncontaminated soil. However, it was observed that the application of these biosurfactants, particularly at the dose of 1000 mg·kg−1 DM, largely decreased the effect of coal tar creosote on the determined parameters. Moreover, the microbial biomass and the activity of ALP and URE were found to be the best indicator of bioremediation of soil contaminated with coal tar creosote.

The experiment was conducted using five species of roses naturally occurring in Poland: Rosa agrestis (fieldbriar rose), R. canina (dog rose), R. dumalis (glaucous dog rose), R. rubiginosa (sweetbriar rose), and R. tomentosa (whitewooly rose), from the in vitro collection of the Department of Ornamental Plants of the University of Agriculture in Kraków. We examined the effect of cytokinin BA (1-10 μM) added to an MS medium (Murashige and Skoog 1962) on auxiliary shoot multiplication. The second group of test media contained BA (1-5 μM) and gibberellin GA3 (0.3-1.5 μM). The cultures were maintained at a phytotron temperature of 23/25°C (night/day), 80% relative humidity, with a 16-hour photoperiod and PPFD of 30 μmol m-2 s-1, and cultured in five-week cycles. The highest multiplication rate was obtained for R. canina and R. rubiginosa (4.1 shoots per one explant) and R. dumalis (2.9 shoots per one explant), when shoots were multiplied on an MS medium supplemented with 1 μM BA and 1.5 μM GA3. Multiplication was the weakest in Rosa tomentosa independent of the medium used.

Trees play a crucial role in the urban environment. They fulfil aesthetic, sociocultural, ecological, health-promoting and economic functions. Urban development and related human activity bring many risks to green areas within urban space. Plants are exposed to stress connected with water, soil and air pollution. Living space, harmful light and thermal conditions, drought, high density and changeable soil pH with excessive salinity are further disadvantages. European and Northern American cities have to cope with a serious danger of tree death. A leading cause is the use of de-icing chemicals in winter, particularly sodium chloride, applied due to its cost-effectiveness and availability. The paper describes traditional de-icing chemicals used in urban areas (NaCl, solid aggregates, CaCl2, MgCl sulphates MgSO4, (NH4)2SO4, urea alcohols and glycols isopropyl alcohol, ethylene glycol, methanol) and newly developed sodium chloride substitutes (calcium magnesium acetate CMA), sodium formate and acetate NaFo/NaAc, potassium carbonate K2CO3). Moreover, prophylactic methods aimed at preventing the negative impact of de-icing campaigns, rules of planning and design of urban landscape, and reasonable management measures and pro-ecological modern technologies reducing and reversing the consequences of harmful actions are presented

In the present studies, an attempt has been made to develop a method of liquid nitrogen preservation of plant explants propagated in vitro in the laboratory of the Department of Ornamental Plants, of Agricultural University in Kraków: shoot apical and axillary meristems of Rosa ‘New Dawn’, somatic embryos of snowdrops Galanthus nivalis L. and G. elwesii Hook, and gametophyte of Phlebodium aureum (L.) J. Sm. (golden polypody). After encapsulation of plant material, it was dehydrated by quick method (capsules were placed in liquid media containing 0.75 M sucrose for 18 h) or by gradual method (capsules were transferred to liquid solutions of media with increasing sucrose concentrations from 0.3 M to 1 M for consecutive 7 days). Moreover, some explants for cryopreservation were treated with the medium containing elevated sucrose level (0.25 M) for 8 weeks

Cities and ports are elements of the socio-economic space of coastal regions and they are integrally interrelated with each other while their development is mutually conditioned. Cooperation of the port and the city usually would bring development of both these elements in the historical perspective. The seaport has always grown and developed along with the city and the region. On the one hand, a port-city performs functions related to maritime economy in the broad sense of the word, i.e. maritime functions, and on the other hand - land functions that result from the city's location in relation to its land base. When the maritime function is overwhelming, the port has a powerful impact on the city, its spatial and economic layout. The very nature of the port has a significant impact on shaping the face of the city and the region. Contemporary cities are currently facing many various problems resulting from their rapid development: debt, commercialization of the public space, degradation of the infrastructure, deteriorating quality of public services, or excessive and inefficient consumption. Since the time concept of sustainable development came into being, it has been adopted as the basis for all activities at various levels of territorial organization, including at the city level. Nonetheless, each tier of development planning has its own specificity, similarly to individual territorial units within a specific tier. This is related but not limited to cities, particularly port-cities, in respect of which sustainable development should be understood a little differently than in other cities, due to the complexity of their relationships and the special role that they play in the economic system. The aim of this article is to indicate such a way of understanding the sustainable development that refers to the specificity of a port-city. Ports and cities interact across many dimensions, however, a more detailed insight how port-cities integrate the port and urban functions is still lacking. The survey conducted among city representatives, businesses and port authorities is to help identify the directions of activities for sustainable development and indicate the common grounds of these activities, where both parties could support each other.