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.
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.
Physical Culture, as a part of general culture, can be defined as a human activity, which, through its knowledge ABOUT and FOR physical exercise within its areas (physical education, sports and physical recreation), allows the transformation of personality from real to possible. Physical Education, as one of the areas of Physical Culture, is therefore a very important educational link. It is particularly important in anera characterized by fast technological advances and technicalism that is rapidly introducing people to virtual reality. Hence, we emphasize that Physical Education, with its knowledge ABOUT and FOR physical exercise, builds the basis for a healthy, active and long life in young people. This is possible due to the fact that Physical Education, based on the Theory of Theoanthropocentrism, sees physical exercise as a beneficial body activity necessary for man and stems from the relationship to a man as a person, not an individual. The increasingly present virtual reality is in complete harmony with the sedentary culture, increasingly dominant not only in Western civilization. This undoubtedly leads to "active" hypokinesia, the root of many disturbing changes and health problems. Anthropological research conducted in Serbia and AP Vojvodina have confirmed that the number of people who regularly engage in physical exercise is decreasing. That is why we point out the importance of Physical Education, which, with its knowledge of how and why to exercise, builds the awareness of the necessity for physical exercise, as well as of the possibility of seeing every physical activity as physical exercise.
Physical movement - an exercise, which springs from our being and returns to it as a gracious food, with its agon, that desire to compete with others but also with itself, helps a human being to become and remain a personality. This statement is confirmed by people who marked the 19th and 20th century. By their example and work, they not only testified the benefits of physical exercise, but also encouraged the formation of theoanthropocentrism, one of the theories of physical culture, at the end of the 20th century. Metropolitan Hadzi Sava Kosanovic, Bishop Rade, Bishop Nikolaj of Zica, Vasa Pelagic, Cedomir Milic, are just some of those who testified and encouraged others by their example not to forget about physical exercise and their body. Because in the union of body and soul sanctified by the Holy Spirit, that trinity survives only if all and each of them is taken care of, in specific. With examples of their attitude towards physical exercise and competition, which they only pointed out or others wrote about, we will lighten up a significant part of the history of physical culture.
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.
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