On the extension of the Erdös-Mordell type inequalities

We discuss the extension of inequality R_A >= c/a * r_b + b/a * r_c to the plane of triangle ABC. Based on the obtained extension, in regard to all three vertices of the triangle, we get the extension of Erdos-Mordell inequality, and some inequalities of Erdos-Mordell type.This is the peer-reviewed version of the article: B. J. Malešević, M. Petrović, M. Obradović, and B. Popkonstantinović, ‘On the extension of the Erdös-Mordell type inequalities’, Mathematical Inequalities & Applications, vol. 17, no. 1, pp. 269–281, 2014, [http://dx.doi.org/10.7153/mia-17-22

Utvrđivanje rezistentnosti Myzus persicae (Sulzer) molekularnim metodama

In two years of investigating resistance of the peach-potato aphid Myzus persicae (Sulzer) by molecular methods, several types of resistance were established in the majority of individuals from peach and tobacco in Serbia and Montenegro. Most of the tested individuals had the FE4 gene, which encodes production of FE4 esterase. The gene responsible for kdr (knock-down resistance) was found in the majority of individuals, but in the heterozygous state, while resistance based on formation of modified acetlycholinesterase (MACE) was least represented. Also, tests showed aphids from tobacco to be more sensitive to insecticide action than aphids from peach. Three tests were used in these investiga­tions, e.g., the PCR - esterase, PCR - kdr, and RFLP - PCR tests, each for a single type of resistance.U dvogodišnjim istraživanjima rezistentnosti zelene breskvine vaši, Myzus persicae (Sulzer) molekularnim metodama, ustanovljeno je da je kod većine testiranih jedinki sa breskve i duvana u Srbiji i Crnoj Gori, utvrđen neki od tipova rezistentnosti. Većina testiranih jedinki imala je FE4 gen koji kodira produkciju FE4 karboksilesteraze. Gen odgovoran za kdr (knock-down rezistentnost) nađen je kod većine jedinki, ali u heterozigotnom stanju dok je rezistentnost koja se zasniva na stvaranju modifikovane acetilholinesteraze (MACE) najmanje zastupljena. Takođe, testovi su pokazali da su vaši sa duvana osetljivije na dejstvo insekticida od vašiju sa breskve. U ovim istraživanjima korišćena su tri testa: PCR-esteraza test, PCR-kdr i RFLP-PCR, svaki za po jedan tip rezistentnosti

Mechanical activation as sintering pre-treatment of talc for steatite ceramics

The effect of vibratory mill induced mechanical activation on the change of the particle size, crystallinity and the phase transformations of the minerals present in the activated material, was studied with the purpose of decreasing of the sintering temperature of talc (Mg3Si4O10(OH)2) as raw material which is the basic component of the steatite ceramics. The aims of the conducted investigation were, also, increasing of the reactivity of the comminuted raw material and establishing of the optimal activation period. The properties of the activated talc induced by mechanical force were expressed in form of the grain inertia change which was measured by means of automatic grain counter. Mechanically activated grains are the most convenient mineral form for physical concentration since the energy change of the mill-material system is recorded on them. The effect of dry grinding on the structure, particle size and shape of talc was studied by means of XRD, DTA and SEM/EDS methods. Activation of talc produced an increase of the starting surface area value progressively from 4.5 m2/g up to a maximum of 108.5 m2/g achieved at 30 min. A subsequent decrease of rate of surface area change and the rate of size reduction were observed following the prolonged grinding. Talc activated in vibratory mill for optimal 30 min showed properties which positively influence the decrease of sintering temperature and the increase of the sintering rate of steatite ceramics. [Projekat Ministarstva nauke Republike Srbije, br. 172057, br. 45008 i br. 33007

Improved Interyarn Friction, Impact Response, and Stab Resistance of Surface Fibrilized Aramid Fabric

Improvement of the ballistic performance of aramid fabric is an important topic in the study of soft body armors, especially with their increasing use in such applications over the past decades. To enhance and tailor the performance of fabrics, having control over one of its primary energy absorption mechanisms, interyarn friction, is required. Here, a recently reported surface fibrilization method is exploited and optimized to improve interyarn friction in aramid fabrics. Through tow pullout testing of fibrilized fabrics, the fibrilization treatment is shown to provide up to seven times higher pullout energy and six times higher peak load. To correlate the effects of the treatment on the ballistic response, impact tests are conducted on treated fabric targets using a gas gun setup. The fibrilized fabrics displayed a 10 m s‐1 increase in V50 velocity, compared to that of untreated fabrics, while retaining its original flexibility and mechanical strength. Similarly, the fibrilization treatment also resulted in 230% improvement in depth of penetration when dynamically stabbed using a spike impactor. The results demonstrate the potential of the proposed surface fibrilization treatment as a fast and cost‐effective technique to improve the ballistic and stab performance of aramid‐based soft body armors.This work shows improved interyarn, ballistic, and stab resistance properties in aramid fabric through a basic fibrilization treatment. The treated aramid fabrics display a maximum improvement of 665% in yarn pullout energy, a 10 m s−1 increase in V50 velocity, and 230% higher stab impact resistance, while maintaining its original tensile properties.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/151907/1/admi201900881.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/151907/2/admi201900881_am.pd

Physico-chemical Properties of Corn Extrudates Enriched with Tomato Powder and Ascorbic Acid

The aim of this research was to investigate the influence of the addition of tomato powder (TP) to corn grits at levels 4, 6 or 8 % and the addition of ascorbic acid (AA) at levels 0.5 and 1 %, on total polyphenol content (PF), and antioxidant activity of the extrudates. The hardness and the expansion ratio of the extruded products were also tested. Mathematical models that describe the influence of additives on the mentioned properties were also determined. Extrusion was performed at two temperature regimes: 135/170/170 °C and 100/150/150 °C. Lower temperature regime led to increased hardness and the expansion of extrudates. The addition of tomato and AA led to decreased hardness and the expansion at both temperature regimes. The addition of tomato increased PF and AA compared with pure corn extrudates. Greater degradation of PF and AA was at lower temperature regime. High correlation between PF and AA was demonstrated at both extrusion temperatures

Injectivity of sections of convex harmonic mappings and convolution theorems

In the article the authors consider the class ${\mathcal H}_0$ of sense-preserving harmonic functions $f=h+\overline{g}$ defined in the unit disk $|z|<1$ and normalized so that $h(0)=0=h'(0)-1$ and $g(0)=0=g'(0)$, where $h$ and $g$ are analytic in the unit disk. In the first part of the article we present two classes $\mathcal{P}_H^0(\alpha)$ and $\mathcal{G}_H^0(\beta)$ of functions from ${\mathcal H}_0$ and show that if $f\in \mathcal{P}_H^0(\alpha)$ and $F\in\mathcal{G}_H^0(\beta)$, then the harmonic convolution is a univalent and close-to-convex harmonic function in the unit disk provided certain conditions for parameters $\alpha$ and $\beta$ are satisfied. In the second part we study the harmonic sections (partial sums) $$s_{n, n}(f)(z)=s_n(h)(z)+\overline{s_n(g)(z)},$$ where $f=h+\overline{g}\in {\mathcal H}_0$, $s_n(h)$ and $s_n(g)$ denote the $n$-th partial sums of $h$ and $g$, respectively. We prove, among others, that if $f=h+\overline{g}\in{\mathcal H}_0$ is a univalent harmonic convex mapping, then $s_{n, n}(f)$ is univalent and close-to-convex in the disk $|z|< 1/4$ for $n\geq 2$, and $s_{n, n}(f)$ is also convex in the disk $|z|< 1/4$ for $n\geq2$ and $n\neq 3$. Moreover, we show that the section $s_{3,3}(f)$ of $f\in {\mathcal C}_H^0$ is not convex in the disk $|z|<1/4$ but is shown to be convex in a smaller disk.Comment: 16 pages, 3 figures; To appear in Czechoslovak Mathematical Journa

Structural characterization and electrical properties of sintered magnesium-titanate ceramics

In this article the influence of ball miling process on structure of MgO-TiO2 system, as well as the electrical properties of samples after sintering, was investigated. The mixtures of MgO-TiO2 powders were mechanically activated in a planetary ball mill for the time period from 0 to 120 min. The influence of mechanical activation and sintering on the lattice vibrational spectra was studied by Raman spectroscopy at room temperature. Structural investigations have been performed on produced powders. Nitrogen adsorption method was used to determine the BET specific surface area and pore size distribution. Unusual results have been obtained: specific surface area continuosly decreased up to 40 min of activation and increased after that, reaching its minimun value of 5.5 m(2)/g. The Raman spectra of activated powders have shown that anatase modes have been decreasing in intensity and broadening as the time of activation extended. Also, the additional modes attributed to TiO2 II, srilankite and rutile phases started to appear as a consequence of activation. The small differences noticed in the Raman spectra of sintered samples have been explained by structural modification of MgTiO3 phase due to the presence of defects. The effects of activation and sintering process on microstructure were investigated by scanning electron microscopy (SEM). The electrical measurements showed difference in dielectric constant (epsilon(r)), loss tangent (tg delta) and specific resistance (rho) as a function of time of mechanical treatment

Phenolics content and antioxidant capacity of commercial red fruit juices

The content of phenolics: total phenols (TP), flavonoids (TF), anthocyanins (TA) and hydroxicinnamic acid as well as the total antioxidant capacity (TAC) in nine commercial red fruit juices (sour cherry, black currant, red grape) produced in Serbia were evaluated. The total compounds content was measured by spectrophotometric methods, TAC was determined using DPPH assays, and individual anthocyanins and hydroxycinnamic acids was determined using HPLC-DAD methods. Among the examined fruit juices, the black currant juices contained the highest amounts of all groups of the phenolics and exhibited strong antioxidant capacity. The amount of anthocyanins determined by HPLC method ranged from 92.36 to 512.73 mg/L in red grape and black currant juices, respectively. The anthocyanins present in the investigated red fruit juices were derivatives of cyanidin, delphinidin, petunidin, peonidin and malvidin. The predominant phenolic acid was neoclorogenic acid in sour cherry, caffeic acid in black currant, and p-coumaric acid in black grape juices. Generally, the red fruit juices produced in the Serbia are a rich source of the phenolic, which show evident antioxidant capacity

Polyphenol content and antioxidant activity of sour cherries from Serbia

The aim of this study is to evaluate the content of phenolics: the total phenols (TP), flavonoids (TF), anthocyanins (TA), as well as the total antioxidant capacity (TAC) in three sour cherry cultivars (Prunus cerasus L.) introduced to the southeast Serbia climate conditions. Among the researched sour cherries, ‘Oblacinska’ cultivar contained the highest amounts of all groups of phenolics, followed by ‘Cigancica’ &gt; ‘Marela’. A significant difference were observed in the phenolic content among different cultivars and growing seasons (p&lt;0.05), and the phenolic compounds were significantly higher in the growing season 2009. The examined cultivars possess a high antioxidant capacity, and all phenolics of highy correlation with TAC. The following compounds were identified and quantified using HPLC-DAD: 4 anthocyanins, the most abundant of which was cyaniding-3-glucoside in ‘Marela’ and ‘Oblacinska’, and cyanidin-3-glucosylrutinoside in ‘Cigancica’, and 4 hydroxycinnamic acids, the most abundant of which was neochlorogenic acid in all sour cherry cultivars. The growing and ripening process on the tree of sour cherry cv. Oblacinska was evaluated, also. The results showed significant increases in total phenols during the ripening, the total anthocyanins and total antioxidant capacity and 4 quantified anthocyanins, however the neochlorogenic acid decreased during the ripening. The study indicated that the growing and climate conditions in southeast Serbia are convenient for introducing sour cherry cultivars

Cross-Lingual Neural Network Speech Synthesis Based on Multiple Embeddings

The paper presents a novel architecture and method for speech synthesis in multiple languages, in voices of multiple speakers and in multiple speaking styles, even in cases when speech from a particular speaker in the target language was not present in the training data. The method is based on the application of neural network embedding to combinations of speaker and style IDs, but also to phones in particular phonetic contexts, without any prior linguistic knowledge on their phonetic properties. This enables the network not only to efficiently capture similarities and differences between speakers and speaking styles, but to establish appropriate relationships between phones belonging to different languages, and ultimately to produce synthetic speech in the voice of a certain speaker in a language that he/she has never spoken. The validity of the proposed approach has been confirmed through experiments with models trained on speech corpora of American English and Mexican Spanish. It has also been shown that the proposed approach supports the use of neural vocoders, i.e. that they are able to produce synthesized speech of good quality even in languages that they were not trained on