NEW TYPE OF NEARLY MONOTONIC PASSBAND FILTERS WITH SHARP CUTOFF

New type of nearly monotonic rational function with one pair of zeros on imaginary axis has been proposed. By using these new functions with zeros as a parameter, it is possible to make tradeoff between minimum stopband attenuation and selectivity of the amplitude characteristic. In order to present efficiency of the proposed filter, comparison with allpole filter monotonic in the passband and inverse Chebyshev filter is presented. Also, design example for the seventh order new type lowpass filter is given

EFFECTIVE COMBINING OF COLOR AND TEXTURE DESCRIPTORS FOR INDOOR-OUTDOOR IMAGE CLASSIFICATION

Although many indoor-outdoor image classification methods have been proposed in the literature, most of them have omitted comparison with basic methods to justify the need for complex feature extraction and classification procedures. In this paper we propose a relatively simple but highly accurate method for indoor-outdoor image classification, based on combination of carefully engineered MPEG-7 color and texture descriptors. In order to determine the optimal combination of descriptors which is characterized by efficient extraction, compact representation and high accuracy, we conducted comprehensive empirical tests over several color and texture descriptors. The optimal descriptors combination was used for training and testing of a binary SVM classifier. We have shown that the proper descriptors preprocessing before SVM classification has significant impact on the final result. Comprehensive experimental evaluation shows that the proposed method outperforms several more complex indoor-outdoor image classification techniques on a couple of public datasets

Biomechanical Modeling of Knee for Specific Patients with Chronic Anterior Cruciate Ligament Injury

In this study we modeled a patient specific 3D knee after anterior cruicate ligament (ACL) reconstruction. The purpose of the ACL reconstruction is to achieve stability in the entire range of motion of the knee and the establishment of the normal gait pattern. We present a new reconstruction technique that generates patient-specific 3D knee models from patient's magnetic resonant images (MRIs). The motion of the ACL reconstruction patients is measured by OptiTrack system with six infrared cameras. Finite element model of bones, cartilage and meniscus is used for determination stress and strain distribution at different body postures during gait analysis. It was observed that the maximum effective von Mises stress distribution up to 8 MPa occurred during 30% of the gait cycle on the meniscus. The biomechanical model of the knee joint during gait analysis can provide insight into the underlying mechanisms of knee function after ACL reconstruction

Trichoderma spp. From pine bark and pine bark extracts: Potent biocontrol agents against botryosphaeriaceae

Pinus sylvestris bark represents a rich source of active compounds with antifungal, antibacterial, and antioxidant properties. The current study aimed to evaluate the antifungal potential of P. sylvestris bark against Botryosphaeria dothidea, Dothiorella sarmentorum, and Neofusicoccum parvum (Botryosphaeriaceae) through its chemical (water extracts) and biological (Trichoderma spp. isolated from the bark) components. The water bark extracts were prepared at two temperatures (80 and 120◦C) and pH regimes (7 and 9). The presence of bark extracts (30%) caused inhibition of mycelial growth of B. dothidea and D. sarmentorum for 39 to 44% and 53 to 60%, respectively. Moreover, we studied the antagonistic effect of three Trichoderma isolates originating from the pine bark. Trichoderma spp. reduced growth of B. dothidea by 67%–85%, D. sarmentorum by 63%–75% and N. parvum by 55%–62%. Microscopic examination confirmed typical mycoparasitism manifestations (coiling, parallel growth, hook-like structures). The isolates produced cellulase, β-glucosidase and N-acetyl-β-glucosaminidase. The volatile blend detected the emission of several volatile compounds with antimicrobial activity, including nonanoic acid, cubenene, cis-α-bergamotene, hexanedioic acid, and verticillol. The present study confirmed in vitro potential of P. sylvestris bark extracts and Trichoderma spp. against the Botryosphaeriaceae. The study is an important step towards the use of environmentally friendly methods of Botryosphaeriaceae disease control

Korelacije strukture i reaktivnosti za kinetiku reakcije sinteze supstituisanih 4-fenil-1,4-dihidropiridina

Quantitative structure-reactivity correlations for the kinetics of the Hantzsch synthesis of 4-(substituted phenyl)-1,4-dihydropyridines in the reaction between ethyl m- and p-substituted 2-benzylideneacetoacetate and the enamine (ethyl 3-aminocrotonate) was studied. The reaction kinetics was followed spectrophotometrically. It was found that the reaction correspond to second-order kinetics. Quantitative structure-reactivity correlations of log k were obtained with the corresponding substituent constants (s, s+, sI and s + ) using the Hammett and extended Hammett equation (dual substituent parameter, DSP, equation). They showed linear relationships with positive values of reaction constants (r). The obtained data were processed by linear regression analysis. It was confirmed that Michael addition of the enamine to benzylidene represented the slow step of the reaction with a high positive charge at the benzylidene molecule. MO calculations were performed and they were in agreement with the conclusions derived from the structure-reactivity correlations. .Proučavan je kvantitativan odnos strukture i reaktivnosti za kinetiku Hančove sinteze supstituisanih 4-fenil-1,4-dihidropiridina u reakciji etil-m- i p-supstituisanih 2-benziliden-acetoacetata i enamina. Kinetika ispitivane reakcije je praćena spektrofotometrijskim metodom. Zapaženo je da je reč o reakciji drugog reda. Kvantitativne korelacije strukture i reaktivnosti koje izražavaju logaritam određene konstante brzine reakcije (log k) u zavisnosti od odgovarajućih konstanti supstituenata (s, s+,sI i s +) određene su za Hametovu (Hammett) i proširenu Hametovu jednačinu (DSP-jednačinu). Pokazale su linearnu zavisnost sa pozitivnim vrednostima nagiba, odnosno reakcione konstante (r). Time je potvrđeno da Majklova (Michael) adicija enamina na benziliden predstavlja spori stupanj u reakciji sa izraženim pozitivnim naelektrisanjem na molekulu benzilidena. MO proračuni su takođe urađeni i njihovi rezultati su bili u skladu sa zaključcima izvedenim iz korelacija strukture i reaktivnosti.

Structure-reactivity correlation for the kinetics of the reaction of substituted 4-phenyl-1,4-dihydropyridines formation

Quantitative structure-reactivity correlations for the kinetics of the Hantzsch's synthesis of substituted 4-phenyl-1,4-dihydropyridines in the reaction between ethyl m- and p-substituted benzylidene acetoacetate and enamine has been studied. The reaction kinetics was followed using spectrophotometric measurements. It was found that the reaction correspond to the second-order kinetics. Quantitative structure-reactivity correlations of log k with the corresponding substituent constants (s,s+,sI and sR+) using Hammett and extended Hammett equation (DSP equation). They show linear relationship with positive values of reaction constants (r). The obtained data were processed by the linear regression analysis. It is confirmed that Michael's addition of enamine to benzylidene represents the slow step of the reaction with high positive charge at the benzylidene molecule. MO calculations were performed and they were also in agreement with the conclusions derived from structure-reactivity correlations. [Projekat Ministarstva nauke Republike Srbije, br. 172013

A study of the barrier properties of polyethylene coated with a nanocellulose/magnetite composite film

The morphological, thermal and barrier properties of low-density polyethylene/polycaprolactone-modified nanocellulose hybrid materials were investigated in this study. Nanocellulose/magnetite (NC-Fe3O4) nanocomposite and maleic acid functionalized NC/magnetite (NCMA-Fe3O4) nanocomposite were prepared and used as fillers at various concentrations (5, 10 and 15 wt. %) in the polycaprolactone (PCL) layer. PE was coated with a PCL/NC//magnetite layer. The addition of the filler did not unfavorably affect the inherent properties of the polymer, especially its barrier properties. Oxygen permeation measurements showed that the oxygen barrier properties of magnetite enriched PCL film were improved due to the chemical activity of the added material. The highest level of the barrier capacity was observed for PE samples coated with a PCL-based composite with NCMA-Fe3O4 micro/nanofiller, which implies a significant contribution of the surface modification of the nanocellulose with maleic anhydride residue to the improved barrier properties

A LFER Kinetic Study of The Reaction of 5-Substituted Orotic Acids with Diazodiphenylmethane

Linear free energy relationships (LFER) were applied to the kinetic data for the reaction of 5-substituted orotic acids, series 1, with diazodiphenylmethane (DDM) in N,N-dimethylformamide and compared with results obtained for 2-substituted benzoic acids, series 2. The correlation analysis of the kinetic data with sigma substituent parameters was carried out using SSP (single substituent parameter) methods. From the sign and value of proportinality constant rho, lower sensitivity to the substituent effect was obtained in series 1, 0.876, than in the series 2, 1.877. Evaluation of substituent "ortho-effect" was performed using the Charton model, which includes the steric substituent parameter, and Fujita and Nishioka's model, which describes the total ortho-effect as contribution of ordinary polar effect, the ortho-steric and ortho-polar effects. Results of correlations, obtained by using the Charton model, showed highest contribution of the polar effect, 0.861 vs. 2.101, whereas the steric effect is of lowest significance, 0.117 vs. 0.055, for series 1 and 2, respectively. Also, a low negative value of coefficient with the steric effect, -0.08, obtained from the Fujita-Nishioka model indicated low steric effect, influencing a decrease of the reaction rate in series 1. The structural and substituent effects were also studied by using the density functional theory method, and together with kinetic data, it gave a better insight into the influence of the effect of both geometry and substituent on the pi-electron density shift induced reactivity of investigated acids. geometry and substituent on the pi-electron density shift induced reactivity of investigated acids