Previous research has shown that there are allelopathic interactions between plants, releasing allelochemicals for which it is still unknown whether they are randomly generated or transmitted from generation to generation. In this paper, the influence dried ragweed leaves (Ambrosia artemisiifolia L.) aqueous extract of different concentrations: concentrated extract (10%), extract diluted to 1/2 (5%); 1/4 (2.5%) and 1/8 (1.25%) on germination and growth of peas and beans was monitored. The results showed that the increased concentration of ragweed extract inhibited germination, prolonged germination time and decreased the germination index of both test plant species compared to the control. The ragweed extract (concentrated and 1/2) reduced the growth of shoots and roots compared to the control (by more than 50%), with the inhibitory effect being more visible on young pea plants compared to beans. The results of the research showed that the presence of ragweed as a weed in the field significantly reduces the germination and growth of cultivated plants, which is why care should be taken to suppress and remove it in a timely manner.
This study aimed to examine radiographs of Thoroughbred horse and compare radiometric and geometrical features between male and female individuals. To this end, dorso-palmar images of the carpal joint of 34 (17 female, 17 male) clinically healthy two-year-old Thoroughbred horses were analyzed. In total, 15 lengths and two angles were analyzed radiometrically, while geometric morphometrics was applied on 20 landmarks. In 7 radiometric measurements, the difference between female and male individuals was found to be statistically significant. All length measurements of males were found to be higher than of females. The statistically most important difference between the sexes was the measurement of the greatest breadth of proximal end of basis metacarpalia II-III-IV (p <0.001). There was no difference between the sexes for angle values. It was seen that the geometric morphometric analysis made with the Landmarks used in the study was not determinative between males and females. Thanks to the developing technology, the number of three-dimensional modeling technique and radiometric measurement studies is also increasing. In this study, the differences between the sexes were revealed using radiographs of horses of the same age, and obtained values will be the references for future radiometric and clinical studies.
3D printing or additive manufacturing is one of the newest technologies that has begun to be used for production of anatomical models in veterinary medicine. The main aim of this research was to evaluate the total cost required for 3D printing of different anatomical models and the cost-effectiveness of use of these technologies in practice. For purpose of this study, we evaluated a cost of 3D printed model of the human heart, inner ear, cross-section of the animal cell and spinal cord, sheep, cow and cat brain and complete dog model with internal organs. The costs were calculated separately for raw material consumption and personnel operative work. The results show that 3D printing technologies are cost-effective for the production of anatomical models, and the total cost depends mostly on working time of the personnel.
The development of science and technology introduces new approaches in plant breeding and various methods to increase plant productivity. One of the latest methods is the implementation of an environmentally friendly technique of using a pulsed low-frequency electromagnetic field (PEMP). The paper presents the results of the influence of the electromagnetic stimulation of soybean seeds on grain weight per plant, weight of 1,000 grains and grain yield in different agroecological conditions. In the three-year research, in the period from 2013 to 2015, the soybean variety Valjevka was used, grown with different amounts of fertilizers (control - without fertilization, 750 kg/ha and 1300 kg/ha). Before sowing, the seed was subjected to PEMP stimulation in variants: control - without stimulation and alternating magnetic field stimulation (PEMP) with induction of 30 mT and exposure time of 15 minutes. The average grain weight per plant during seed stimulation was 11.53% (12.09) higher than without PEMP (10.84). The weight of 1,000 grains with PEMP was 155.99 g, which was 2.06% higher than the weight of 1,000 grains of the variant without PEMP (152.83 g). The average soybean grain yield for all three years of research with seed stimulation was 4.85% higher (3,481.25 kg/ha) than without PEMP (3,320.14 kg/ha). Stimulation of seeds with PEMP has economic justification given the growth of soybean prices on the world stock market. The results show that the PEMP treatment of soybean seeds can significantly affect soybean grain yield and counteract side effects such as drought and lack of fertilizers.
Ancient Roman concrete constitutes many ancient structures that remain standing; however, little is known about how it has remained durable. Here, we investigate the mortars used in ancient water bearing infrastructure such as aqueducts, cisterns, and baths. In these structures, crushed ceramics are used as a pozzolanic additive on surfaces in continuous or frequent contact with water. The ceramic-lime mortars are probed using a multi-scale characterization approach including SEM-EDS and Raman microspectroscopy. The analysis shows the role of ceramics within these structures as a source of aluminosilicates, mapping the presence of both pozzolanic and post-pozzolanic phases. A hybrid binder consisting of cementitious hydrates and calcite is mapped at the interface of the ceramics and evidence of post-pozzolanic densification of pores and cracks is observed. Comparison across structures shows that material selection and chemistry benefit the infrastructure applications. Understanding these ancient materials provides inspiration for new, durable infrastructure materials.
This paper presents new records and noteworthy data on the following taxa in SE Europe and adjacent regions: diatom alga Stauroneis neofossilis, parasitic fungus Anthracoidea arenariae, horsetail Equisetum hyemale, liverwort Harpanthus flotovianus, mosses Fissidens exilis and Rhizomnium punctatum, monocots Epipactis helleborine subsp. orbicularis, Himantoglossum calcaratum subsp. rumelicum and Schoenus nigricans and dicots Calluna vulgaris, Mahonia aquifolium and Willemetia stipitata subsp. albanica.
Existing standards require welded joints with full penetration. It is considered that welded joints with complete penetration minimize the stress concentration in the root passage. However, there are numerous situations in the industry, in which the load-bearing capacity of the welded joint with partial penetration is satisfactory. If the tests of partially penetrated welds show satisfactory load capacity, the benefits compared to fully penetrated welds are reflected in lower costs, ie less time is required to prepare the joint, less additional material is needed, ie shorter time is required to make the welded joint. The paper presents the testing of butt welded joints of structural steel S355N, with partial penetration, achieved by the MAG welding in the overhead position (PD) in the protection of the gas mixture. The samples were welded with different welding parameters and with different joint preparation, and the tests were performed by non destructive methods (visual inspection, testing with penetrants and magnetic particles) and destructive methods - tension and bending tests, Vickers hardness testing.
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