Dragana Sumarac Pavlovic

Phytotherapy in medieval Serbian medicine according to the pharmacological manuscripts of the Chilandar Medical Codex (15-16th centuries).

The Chilandar Medical Codex is the most significant and best preserved medieval Serbian manuscript and collects together documents on European medical science from the 12th to 15th centuries. It represents the best-known and most complete example of a large collection of medical manuscripts from the Salerno-Montpellier school, written in the vernacular - something which does not exist among the majority of European nations. This paper presents the section of the Codex that deals with phytotherapy, which is contained within the pharmacological manuscripts. An analysis of their contents shows that out of a total of 167 recorded substances, 135 are of plant origin (81%), 13 animal origin (7.7%) and 19 inorganic (11.3%). The recorded plant species are categorised into 63 families, of which the most frequent are: Apiaceae (8.1%), Lamiaceae (8.1%), Asteraceae (5.9%), Rosaceae (5.9%) and Fabaceae (4.4%). All possible plant parts were used in treatments: the whole plant (6%), underground parts (13.7% - root, rhizome, bulb) and aerial parts (80.3% - stem, leaf, flower, buds, fruit, seeds). Of the plants quoted, the following are mentioned most frequently: Vitis sp. (120), Rosa canina (55), Olea europaea (45), Pistacia lentiscus (25), Saccharum officinarum (23), Artemisia absinthium (16) and Foeniculum vulgare (15). The contents of the pharmacological manuscripts of the Chilandar Medical Codex point to the sound contemporary knowledge of the diversity of plant species, their origins, habitat types, the levels of their healing powers, and when and how to gather them and prepare them, as well as the recommended dose for the treatment of specific illnesses. As these manuscripts contain not only common, lay terms for the plants, but also scientific, botanical ones, we can consider them the precursor to Serbian botany. Based on its contents and the way in which they are presented, it can be viewed not only as the first Serbian pharmacopeia, but first Slavic pharmacopeia, too, because similar manuscripts written in the vernacular did not exist during that period among the other Slavic nations, or even most European nations.

Assessment of the contamination of riparian soil and vegetation by trace metals — A Danube River case study

The aim of this study was to assess the spatial distribution of arsenic and heavy metals (Cd, Cr, Cu Hg, Ni, Pb and Zn) in a riparian area influenced by periodical flooding along a considerable stretch of the Danube River. This screening was undertaken on soil and plant samples collected from 43 sites along 2386 km of the river, collected during the international Joint Danube Survey 3 expedition (ICPDR, 2015). In addition, data on the concentration of these elements in river sediment was used in order to describe the relationship between sediment, riparian soil and riparian plants. A significant positive correlation (Spearman r, for p<0.05) was found for trace metal concentrations in river sediment and soil (r=0.817). A significant correlation between soil and plants (r=0.438) and sediment and plants (r=0.412) was also found for trace metal concentrations. Elevated levels of Cd, Cr, Cu, and Ni were found at certain sites along the Serbian stretch, while elevated concentrations of Hg were also detected in Hungary, of Pb along the Romanian stretch and of As along the Bulgarian stretch (the Lower Danube). These results point to the presence of naturally-occurring metals derived from ore deposits in the Danube River Basin and anthropogenic metals, released by mining and processing of metal ores and other industrial facilities, which are responsible for the entry of metals such as Cu, Ni and Zn. Our results also indicated toxic Cd and Zn levels in plant samples, measured at the Hercegsznato site (Middle Danube, Hungary), which highlighted these elements as a potential limiting factor for riparian vegetation in that area. The distribution of the analysed elements in plant material also indicates the species-specific accumulation of trace metals. Based on our results, the Lower and Middle Danube were found to be more polluted in terms of the analysed elements.

Traditional wound-healing plants used in the Balkan region (Southeast Europe)

ETHNOPHARMACOLOGICAL RELEVANCE The geographical and ecological specificity of the Balkan Peninsula has resulted in the development of a distinct diversity of medicinal plants. In the traditional culture of the Balkan peoples, plants have medicinal, economic and anthropological/cultural importance, which is reflected in the sound knowledge of their diversity and use. This study analyses the traditional use of medicinal plants in the treatment of wounds and the pharmacological characteristics of the most frequently used species. MATERIALS AND METHODS A detailed analysis of the literature related to ethnobhe uses of medicinal plants in the Balkan region was carried out. Twenty-five studies were analysed and those plants used for the treatment of wounds were singled out. RESULT An ethnobotanical analysis showed that 128 plant species (105 wild, 22 cultivated and 1 wild/cultivated) are used in the treatment of wounds. Their application is external, in the form of infusions, decoctions, tinctures, syrups, oils, ointments, and balms, or direct to the skin. Among those plants recorded, the most commonly used are Plantago major, Hypericum perforatum, Plantago lanceolata, Achillea millefolium, Calendula officinalis, Sambucus nigra, Tussilago farfara and Prunus domestica. The study showed that the traditional use of plants in wound healing is confirmed by in vitro and/or in vivo studies for P. major and P. lanceolata (3 laboratory studies for P. major and 2 for P. lanceolata), H. perforatum (5 laboratory studies and 3 clinical trials), A. millefolium (3 laboratory studies and one clinical trial), C. officinalis (6 laboratory studies and 1 clinical trial), S. nigra (3 laboratory studies) and T. farfara (one laboratory study). CONCLUSION The beneficial effects of using medicinal plants from the Balkan region to heal wounds according to traditional practices have been proven in many scientific studies. However, information on the quantitative benefits to human health of using herbal medicines to heal wounds is still scarce or fragmented, hindering a proper evaluation. Therefore, further studies should be aimed at isolating and identifying specific active substances from plant extracts, which could also reveal compounds with more valuable therapeutic properties. Furthermore, additional reliable clinical trials are needed to confirm those experiences encountered when using traditional medicines. A combination of traditional and modern knowledge could result in new wound-healing drugs with a significant reduction in unwanted side effects.

Engineering practice: Teaching ill-structured problem solving in an internship-like course

Engineering graduates who enter the work environment after finishing their studies are faced with completely different setting compared to the safe academy environment that they are used to. Main differences at the workplace include dealing with uncertainty on a daily basis, solving open-ended and/or ill-structured problems and having to manage teamwork and communication on different educational and professional levels. Students should be faced with these aspects of engineering practice during their studies in order to prepare for work. As conventional engineering curricula often do not provide opportunities for such a practice, we designed the internship-like course with general objective to provide this opportunity for final year students and to define teaching strategies that can support students in the transition from the academy to the workplace. In this paper we describe main issues and challenges of the learning experiences that we found during our action research over four 10 week courses, from 2010/2011 to 2012/2013.

Microphone array geometry optimization for traffic noise analysis

This paper outlines an approach for obtaining microphone array geometry for use in traffic noise analysis. The designed array has a smaller number of microphones compared to existing solutions, thereby reducing the cost of system realization. The array geometry is irregular, consists of 24 microphones, and was obtained by an optimization procedure that minimizes beampatterns sidelobes. Microphone position optimization was performed in the frequency band from 300 Hz to 2000 Hz, defined by traffic noise characteristics. The designed array is used in ongoing research dedicated to the analysis of angular distribution of incident traffic noise sound energy impeding a facade in urban environment.

Measurement of reverberation gain in an urban environment

Multipath propagation within an urban area introduces a specific type of reverberation in response to sound excitation. That appearance affects the level of ambient noise produced by strong sound sources. In this paper, the signals recorded during the 1999 bombing of Belgrade were used to analyze the characteristics of reverberation in that urban environment. Six recorded signals were selected among more than 50 explosions recorded at that time. Due to the impulse nature of sound sources, the recorded signals represent the impulse responses of that area. The measured reverberation time T30 is about 7 ± 1 s in octaves between 31.5 Hz and 1 kHz. There is a variation of decay slope in time that is verified by differences between values of T10 and T30. The reverberation gain calculated from recorded signals is 2-7 dB, depending on the global position of the sound excitation point as well as its micro-location according to its position among the surrounding buildings. A variation of gain over octave bands is in the interval of approximately 3 dB. Information about reverberation gain in urban environment can be useful in a quick estimation of noise level produced by strong sound sources in a large area of urban environment.

The influence of absorption on statistical distribution of free path lengths in rooms

The ray tracing method in sound field simulation in a room allows the calculation of the free path lengths distribution (FPL) by superimposing all rays paths generated in the analysis. In room acoustics the statistical theory of sound field defined this distribution as an indicator of room geometrical properties which are independent of absorption. Accordingly, some commercial softwares for ray tracing simulation allow user to calculate that global distribution of FPL only. This paper is concerned with the analysis of the changes in the shape of FPL distribution as a consequence of nonuniform arrangement of absorption in room. Particularly is analysed the impact of absorptive auditorium in different global forms of the halls where all other interior surfaces are acoustically hard.

Calculation of sound insulation according to EN 12354: Influence of type of the separating element junctions

Separating element junctions make a dual contribution in the calculations of sound insulation according to EN 12354 standards. Junction types and vibration reduction index values determine the amount of the vibration energy which will be transmitted from the separating to the flanking elements, and therefore the flanking transmission between the source and the receiving room. On the other hand, vibration reduction index values influence the structural reverberation time of the element, by quantifying energy losses at its junctions. The aim of this work is to quantify the influence of the separating element junction types on the calculated value of airborne and impact sound insulation.

Calculation of sound insulation according to EN 12354: Influence of sound reduction index of flanking elements

EN 12354 standards describe models for calculation of sound insulation in buildings. EN 12354-1 defines a model for airborne sound insulation, while EN 12354-2 describes the calculation procedure for impact sound insulation. Although the calculated value of sound insulation in both cases depends mostly on the insulation properties of the separating element, flanking transmission is also treated. The aim of this work is to assess the influence of sound reduction index of flanking elements (walls, floors and ceilings) on the calculated value of airborne and impact sound insulation.

Variation of mean free path length over time and its effect on room impulse response

In their previous paper (Forum acusticum 2005, Proceedings, 2399‐2404) the authors presented the local effect found in a large sports hall, described as significantly shorter reverberation time in the first 400‐500 ms than that in the rest of the halls long impulse response. To analyse this phenomenon, a new measure ‐ mean free path length (MFPL) variation in time over the impulse response ‐ was introduced. It is identified as the function of time obtained as an ensemble average in some fixed interval traced along the impulse response duration. The ray tracing simulation was used to calculate ray paths approaching the receiver in time. Analyzing MFPL variations over time is a new insight into the structure of room impulse response, and this paper presents its main characteristics, its dependence on geometrical properties of rooms, and also its relation to statistically defined mean free path length (4 V/S). The paper also presents a correlation between MFPL variation over time and the sound decay curve. The MFPL variation over time reveals the causes of the local effect introduced in the previous paper, but it is generally useful in explaining the sound decay monotony deviations.