bluuebunny/crossref_metadata_2025 huggingface dataset:
Produção de mudas de Moringa oleifera em diferentes concentrações de lodo de esgoto tratado com calcário
Authors: Sousa Alex Nascimento de , Almeida Débora de Melo , Braga Rodolpho Stephan Santos , Barbosa Júnior Vital Caetano , Santana José Augusto da Silva , Canto Juliana Lorensi do
Published: August 2020

A produção de mudas é um aspecto importante quando se quer obter um produto de boa qualidade. Entre os procedimentos realizados para essa atividade, a escolha do substrato possui uma grande importância, pois define os parâmetros de qualidade das mudas produzidas. Dentre as alternativas, o lodo de esgoto pode ser utilizado como substrato, associando sua utilização com a produção de mudas de Moringa oleifera, espécie que atualmente vem sendo alvo de diversos estudos, devido a suas caraterísticas morfológicas e nutricionais. Assim, o objetivo deste trabalho foi avaliar o crescimento de mudas de Moringa oleifera em diferentes concentrações de lodo de esgoto tratado com calcário. As sementes foram coletadas na área experimental da Escola Agrícola de Jundiaí (EAJ). O lodo foi fornecido pela estação de tratamento de esgoto da Universidade Federal do Rio Grande do Norte (UFRN). O experimento foi conduzido em casa de vegetação na EAJ. O tratamento do lodo foi realizado em temperatura ambiente com calcário para sua higienização. O experimento compreendeu seis tratamentos: T0: 100% areia (controle); T20: 20% de biossólido + 80% de areia; T40: 40% de biossólido + 60% areia; T60: 60% de biossólido + 40% areia; T80: 80% de biossólido + 20% areia; T100: 100% de biossólido. Totalizando-se 32 unidades amostrais (repetições) para cada tratamento. Os dados foram analisados no programa Bioestat. De acordo com as análises realizadas, as mudas submetidas aos tratamentos T0, T80 e T100 tiveram crescimento em altura inferior às mudas dos outros tratamentos, onde os melhores resultados foram para o T20, T40 e T60. Não houve diferença estatística entre os valores médios de diâmetro do coleto das mudas nos tratamentos com a presença do lodo, havendo apenas diferença destas para as mudas submetidas ao tratamento controle (T0). As mudas submetidas ao T60 apresentaram melhores resultados de crescimento em altura, relação H/D e número de folhas. Não houve diferença nas médias das variáveis PMSA, PMST e IQD, diferente do que ocorreu com a PMSR e a razão PMSA/PMSR, onde houve diferença estatística, se sobressaindo com maiores médias o T0 e o T60, respectivamente. Pode-se concluir que as concentrações de lodo que apresentaram melhores resultados foram de 40 e de 60%. Observou-se menor crescimento das mudas submetidas aos tratamentos controle (T0), T80 e T100. Portanto, o uso de lodo para a produção de mudas é uma alternativa tecnicamente viável.
Frequência do consumo de carne suína no município de Palmeira dos Índios/AL, Brasil
Authors: Teixeira Joseane Júlia , Oliveira Thiago Soares de , Biserra Caio Henrique de Oliveira Lamenha , Silva José Jardel Leite da , Silva José Crisólogo de Sales
Published: August 2020

A carne suína é bem presente na mesa dos brasileiros, porém a falta de um estudo detalhado do perfil socioeconômico dos consumidores da cidade de Palmeira dos índios, Alagoas, Brasil e da frequência desse consumo atualizado é necessário. Neste trabalho objetivou-se quantificar a frequência do consumo e identificar os cortes cárneos suínos de acordo com sexo, renda, idade e escolaridade dos consumidores no município de Palmeira dos índios. Foram aplicados 100 questionários com 13 perguntas estruturadas de múltiplas escolhas, onde 50 questionários foram aplicados na zona urbana e outros 50 na zona rural, aplicados em feiras livres, residências e estabelecimentos comerciais. Os entrevistados foram aleatoriamente escolhidos, visando ter uma amostragem ampla. Dentre os 100 entrevistados 53% eram mulheres e 47% eram homens, onde a maioria, 25%, tinha mais de 50 anos. O maior consumo diário segundo a pesquisa foi a carne de frango, a suína foi a terceira mais consumida com 8% da preferência. Conclui se assim que a carne suína é consumida por todas as classes sociais do município de Palmeira dos Índios, sendo a terceira em consumo e o corte mais apreciado da mesma é a bisteca.
Avaliação da atividade mutagênica e antimutagênica da Chamomilla recutita (L.) Rauschert, em teste de Allium cepa
Authors: Gallo Cibele Merched , Oliveira José Dailson Silva de , Santos Everton Ferreira dos , Carvalho Filho Renato Vieira de , Silva Wyslane Larissa Almeida Santos Rocha e , Martino-Roth Maria da Graça
Published: August 2020

O uso de Chamomilla recutita como chá calmante, antiinflamatório, analgésico é baseado no conhecimento empírico das plantas medicinais. Este trabalho visa avaliar o potencial mutagênico e antimutagênico, através do teste de Allium cepa, da infusão de flores secas de camomila. Foram realizados onze tratamentos com quatro repetições cada: T1 – controle negativo; T2- paracetamol, 800mg L-1 (controle positivo); T3- camomila na dose usual, 12g L-1; T4- 60g de camomila L-1; T5- 120g L-1 de camomila; Co-tratamentos: T6- paracetamol 800mg L-1 e camomila 12g L-1; T7- paracetamol 800mg L-1 e camomila 60g L-1; T8- paracetamol 800mg L-1 e camomila 120g L-1; T9- paracetamol 800mg L-1 e, 24 horas após, camomila 12g L-1; T10- paracetamol 800mg L-1 e, 24 horas após, camomila 60g L-1; T11- paracetamol 800mg L-1 e, após, camomila 120g L-1. Observou-se que tanto a infusão de 12g L-1 quanto as mais concentradas diminuíram significativamente o índice mitótico. Quanto às anomalias mitóticas, apenas o T11 aumentou significativamente em relação ao T1 (p=0,012). Todos os tratamentos aumentaram a freqüência das anomalias interfásicas de forma significativa (p<0,018), em relação ao T1, havendo também aumento do total de anomalias (p<0,018). Porém tanto os co-tratamentos como os pós-tratamentos diminuíram as anomalias em relação ao controle positivo. Estes resultados demonstram que a camomila teve um efeito citotóxico, e protetor em relação ao controle positivo, nas células meristemáticas de Allium cepa.

Palavras-chave: camomila, antimutagenicidade, mutagenicidade.
Fixed airflow obstruction in patients with asthma
Authors: Sergeeva G. R. , Emel'yanov A. V. , Leshenkova E. V. , Znakhurenko A. A. , Asatiani N. Z. , Rumyantsev A. Sh.
Published: August 2020

According to international guidelines in recent years, it has been proposed that bronchial asthma (BA) with fixed airflow obstructions (FAO) be identified as a separate phenotype.

The aimof the study was the clinical and functional characterization and identification of risk factors for the formation of the phenotype BA with FAO.

Materials.We examined adult outpatients with BA (n = 432) and a combination of BA and chronic obstructive pulmonary disease (COPD) without exacerbation (n = 58). Anamnesis collection, objective examination, spirometry with the assessment of obstruction reversibility (spirograph 2120 Vitalograph, UK), atopic status assessment (skin samples or specific IgE in serum) were performed. The level of eosinophils and neutrophils in peripheral blood was determined (by the impedance method on the automatic haemoanalyzer). Nitric oxide of exhaled air was measured by a chemiluminescent gas analyzer (Logan 4100, UK). BA control and quality of life of patients were evaluated using the Russian language versions of the Asthma Control Questionnaire (ACQ-5) and the St. George's Hospital Respiratory Questionnaire (St. George's Respiratory Questionnaire – SGRQ) respectively. Statistical analysis was carried out using parametric and non-parametric methods using the application program package Statistica 10. The value of bilateral p < 0.05 was considered statistically significant.

Results.Among patients with BA without COPD, the incidence of FAO was 31%, with the most frequent (60%) FAO was found in severe BA and less often – in the mild (7%) and medium (36%) course of the disease. Among patients with a combination of BA and COPD, a severe course of the disease prevailed – 77%. Patients with FAO were older and had a longer duration of disease. The presence of FAO was accompanied by lower rates of pulmonary function, a higher frequency of positive markers of eosinophilic inflammation, worse indicators of control over BA and quality of life, a higher need for “emergency” drugs and drugs to support the treatment of BA, including biological therapy, increased use of healthcare resources. The risk factors for FAO in patients with BA include the debut of BA under 25 years of age (odds ratio (OR) – 1.6), sensitization to ticks of house dust (OR – 1.8), passive smoking (OR – 6.5), suffered during the life of pneumonia (OR - 3.0).

Conclusion. The combination of BA + FAO can be considered as a separate phenotype of the disease with a more severe course and less favorable prognosis.
Inhalation glucocorticosteroids in the treatment of chronic obstructive pulmonary disease
Authors: Avdeev S. N. , Aisanov Z. R. , Arkhipov V. V. , Belevskiy A. S. , Leshchenko I. V. , Ovcharenko S. I. , Emel'yanov A. V. , Demko I. V. , Ignatova G. L. , Trofimenko I. N. , Shmelev E. I.
Published: August 2020

The main objectives of chronic obstructive pulmonary disease (COPD) therapy are to reduce the severity of symptoms and the risk of exacerbations. The article discusses the role of local and systemic inflammation in the pathogenesis of COPD as well as various mechanisms of pharmacological influence on it. Approaches to prescribing basic therapy for patients with COPD, recommended by various national and global guidelines (clinical recommendations of the Russian respiratory society, criteria of the Global Initiative for Chronic Obstructive Lung Disease (GOLD), guidelines of the National Institute for Health and Clinical Excellence (NICE)), as well as recommendations on the therapy frequency review are considered. Currently, so-called triple combinations – fixed combinations of double bronchodilators with inhaled glucocorticosteroids – are being developed and registered in the world, and their place and significance in the treatment of COPD raise many discussions. The paper discusses the role of fixed triple combinations in reducing the incidence of COPD exacerbations, the impact on functional and patient-reported outcomes, and provides recommendations for the use of triple combinations in patients with COPD, taking into account the benefit/risk ratio.
Structurally topological algorithm for star recognition and near-Earth space’ object detection
Authors:   Moscow State University of Geodesy and Cartography (MIIGAiK), Zhurkin I.G. , Chaban L.N. ,   Moscow State University of Geodesy and Cartography (MIIGAiK), Orlov P.Yu. ,   Moscow State University of Geodesy and Cartography (MIIGAiK)
Published: August 2020

When solving a variety of celestial navigation tasks there is a problem of determining parameters of spacecraft motion and onboard primary payload orientation based on the coordinates of registered star images. Furthermore, unwanted objects, like active satellites, natural and artificial space debris, that reduce the probability of correct recognition may get into the field of view of a satellite sensor. This prompts the necessity to filter out such interference from the star field images. However, if the objects under recognition are bodies located in near-Earth space, in this case, the star images themselves will act as interferences. In addition, since the detection and cataloging of these objects from the Earth’s surface is complicated by their small size, the atmospheric effects, as well as other technical difficulties, it is worthwhile to use the existing equipment onboard spacecrafts to solve this task. The existing recognition algorithms for star groups, as well as their classification, are presented in this paper. Moreover, a structurally topological approach for identifying groups of stars based on the properties of enveloping polygons used in constructing topological star patterns is proposed. Specific features in the construction of topological configurations on the analyzed set of points, as well as the principles of dynamic space object detection within their limits are described. Results of the numerical experiments performed using the developed algorithm on the star field maps and model scenes are presented.
Optimal planning of networks of mobile objects under uncertainty
Authors:   Samara National Research University, Mostovoy Y.A. , Berdnikov V.A. ,   Samara National Research University
Published: August 2020

When solving a given common task, a swarm of moving objects coordinates the state of its individual members. When planning swarm operations, there is a need to take into account the possibility of its operational regrouping, since at the time of planning the exact purpose of the swarm operation may be either not yet defined, or secret, or determined by a number of random circumstances. At the same time, the swarm resources are insufficient for one-time coverage of all possible targets in a given service area. Therefore, the execution of the operation of the swarm begins to resolve the aforementioned uncertainties. In this case, the operation time can be significantly reduced. This problem is solved by methods of the percolation theory. A concept of programmable percolation of the service area, which is implemented in two phases, is introduced. The value of the concentration of objects in a basic stochastic swarm is obtained numerically -- using the results of statistical modeling of two-phase operations -- and analytically, providing a minimum total cost of the two-phase operation. The synergy of information interaction between the swarm objects when implementing a programmable percolation path is analyzed.
Camera parameters estimation from pose detections
Authors:   Samsung-MSU Laboratory, Lomonosov Moscow State University, Shalimova E.A. , Shalnov E.V. ,   Samsung-MSU Laboratory, Lomonosov Moscow State University, Konushin A.S. ,   Samsung-MSU Laboratory, Lomonosov Moscow State University,   Samsung AI Center
Published: August 2020

Some computer vision tasks become easier with known camera calibration. We propose a method for camera focal length, location and orientation estimation by observing human poses in the scene. Weak requirements to the observed scene make the method applicable to a wide range of scenarios. Our evaluation shows that even being trained only on synthetic dataset, the proposed method outperforms known solution. Our experiments show that using only human poses as the input also allows the proposed method to calibrate dynamic visual sensors.
A method of contour detection based on an image weight model
Authors:   Kazan National Research Technical University named after A.N.Tupolev-KAI, Gizatullin Z.M. , Lyasheva S.A. ,   Kazan National Research Technical University named after A.N.Tupolev-KAI, Morozov O.G. ,   Kazan National Research Technical University named after A.N.Tupolev-KAI, Shleymovich M.P. ,   Kazan National Research Technical University named after A.N.Tupolev-KAI
Published: August 2020

In this paper a new method for contour detection in grayscale images is proposed. The pro-posed method is based on the use of an image weight model, which allows one to estimate its pix-els from the point of view of their significance for perception. In this case, the most significant pixels are those that contain characteristic features of the image, including brightness differences at the boundaries of the regions. To assess the significance of pixels, we propose a procedure for analyzing the contribution of the corresponding wavelet coefficients at different scale levels to the total energy of the image. The described method of contour detection involves building an image weight model, determining the directions of linear segments along the edges on the weight image, analyzing the significance of pixels and linking significant pixels. The advantage of the method is the high operation speed (the corresponding loop detector works on average four times faster than the Canny edge detector). In addition, the paper describes a detector of significant image areas, which is also based on the weight model. The proposed approach can be used in various systems of information processing and control based on methods and tools of computer vision, including control and navigation systems of unmanned vehicles, remote sensing of the Earth, systems for pavement defect detection, biometric systems, etc.
Quality control method of the transmission of fine image details in the JPEG2000
Authors:   Pacific National University, Sai S.V. , Shoberg A.G. ,   Pacific National University
Published: August 2020

The article proposes a method for controlling the transmission quality of fine image details in the JPEG2000 standard based on an automatic adjustment of the quantization parameters of discrete wavelet transform (DWT) coefficients. An algorithm for setting up quantization scale parameters for different transformation sub-ranges of the DWT coefficients depending on given (permissible) distortions is described. For an objective assessment of image quality, numerical measures of fine detail distortion in a normalized N-CIELAB colorimetric system are used, according to which an analysis of their structural features is performed. Results of the experimental studies of the analysis of image quality and compression efficiency depending on the quantization parameters utilized in the developed adaptive compression algorithm are presented. Results of evaluating the algorithm performance that can be used for practical applications in multimedia applications are also presented.
Incremental learning of an abnormal behavior detection algorithm based on principal components
Authors:   Lobachevsky State University of Nizhny Novgorod, Shatalin R.A. , Fidelman V.R. ,   Lobachevsky State University of Nizhny Novgorod, Ovchinnikov P.E. ,   Lobachevsky State University of Nizhny Novgorod
Published: August 2020

In this paper, we propose an incremental learning scheme for the abnormal behavior detection algorithm based on principal component. The results obtained on a UCSD dataset and our experimental videos at a different number of training samples show that error rates are similar to conventional learning. Moreover, the proposed scheme allows the incremental learning time to be significantly reduced in comparison with a method based on matrix eigendecomposition.
Crop growth monitoring through Sentinel and Landsat data based NDVI time-series
Authors:   Samara National Research University, Boori M.S. ,   American Sentinel University,   University of Rennes 2, Choudhary K. ,   Samara National Research University,   The Hong Kong Polytechnic University,   University of Rennes 2, Kupriyanov A.V. ,   Samara National Research University,   IPSI RAS – Branch of the FSRC “Crystallography and Photonics” RAS
Published: August 2020

Crop growth monitoring is an important phenomenon for agriculture classification, yield estimation, agriculture field management, improve productivity, irrigation, fertilizer management, sustainable agricultural development, food security and to understand how environment and climate change effect on crops especially in Russia as it has a large and diverse agricultural production. In this study, we assimilated monthly crop phenology from January to December 2018 by using the NDVI time series derived from moderate to high Spatio-temporal resolution Sentinel and Landsat data in cropland field at Samara airport area, Russia. The results support the potential of Sentinel and Landsat data derived NDVI time series for accurate crop phenological monitoring with all crop growth stages such as active tillering, jointing, maturity and harvesting according to crop calendar with reasonable thematic accuracy. This satellite data generated NDVI based work has great potential to provide valuable support for assessing crop growth status and the above-mentioned objectives with sustainable agriculture development.
Hybrid Tamm-cavity modes in photonic crystal with resonant nanocomposite defect layer
Authors:   Siberian Federal University, Vetrov S.Ya. ,   Kirensky Institute of Physics, Federal Research Center KSC SB RAS, Avdeeva A.Yu. ,   Kirensky Institute of Physics, Federal Research Center KSC SB RAS, Pyatnov M.V. ,   Kirensky Institute of Physics, Federal Research Center KSC SB RAS,   Siberian Federal University, Timofeev I.V. ,   Kirensky Institute of Physics, Federal Research Center KSC SB RAS,   Siberian Federal University
Published: August 2020

Hybrid optical modes in a one-dimensional photonic crystal with a resonant nanocomposite defect bounded by a metallic layer are studied. The nanocomposite consists of spherical metallic constituents, that are distributed in a dielectric matrix. Transmittance, reflectance, and absorbance spectra of this structure, which is shined by light with normal incidence, are calculated. The possibility of control of the hybrid modes spectral characteristics by changing the thickness of the layer adjacent to the metal, the number of layers, and the nanocomposite filling factor is shown.
The use of reference marks for precise tip positioning in scanning probe microscopy
Authors:   Udmurt Research Center, Ural Branch of the Russian Academy of Sciences, Gulyaev P.V.
Published: August 2020

The article discusses techniques for the precise positioning of a probe tip on the surface under study in scanning probe microscopy. The precise tip positioning is of high importance when studying the same sample with various microscopes, probes, in various environments and conditions. It is offered that the precise positioning should be done by applying on the surface equidistant reference marks with a nanoindentor along a straight line. The article describes a procedure for shifting the microscope’s field of view for detecting the reference marks and subsequently moving the probe along the marks line. A reference marks recognition algorithm is presented. The algorithm is based on the image correlation analysis using a master mark image and the subsequent extraction of special points (at local maxima of the correlation coefficient). A descriptor of mutual distances between the special points and the Pearson coefficient (аs a quantitative criterion of recognition) are used for recognition. Three types of reference marks are considered: a circle, a circle with gradient filling, and a circle with continuous filling. It is shown that the number of the allocated special points can be significantly larger than that of the reference marks. A method for filtering special points is offered. The method is based on the threshold filtering of special points using values of the correlation coefficient. The filtering consists in excluding those special points in whose neighborhood the difference of the maximum and minimum of the correlation coefficient does not exceed a preset threshold. Results confirming the effectiveness of the offered filtering method are presented. Recommendations for choosing the parameters of the recognition and filtering algorithms are given.
Waveguided modes in a planar structure «graphene – thin semiconductor film – graphene»
Authors:   Ulyanovsk State University, Abramov A.S. , Evseev D.A. ,   Ulyanovsk State University, Sementsov D.I. ,   Ulyanovsk State University
Published: August 2020

We investigated optical-range waveguide modes propagating in a semiconductor film sandwiched between two graphene plates. The mode characteristics were shown to depend on the chemical potential of graphene and the film thickness. Based on the numerical analysis, we obtained dispersion relations for the first waveguide modes, frequency dependences of their group and phase velocities, and the distribution of the energy flux density in the structure. We discovered the presence of spectral bands characterized by small phase and negative group velocities of the waveguide modes. The possibility of tuning the waveguide mode by changing the chemical potential of graphene and the thickness of the semiconductor film was established.
Diffraction in grating optical filters with angular-selective light transmission
Authors:   Orenburg State University, Zakirullin R.S.
Published: August 2020

The effect of diffraction on the directional light transmittance of grating optical filters designed for smart windows is studied. The filter has an angular selective light transmission due to two thin-film gratings formed by "non-transmissive" (absorptive, reflective or scattering) parallel strips on the surfaces of a single or double glazed window. Methods are considered for calculating the op-timal slope angle of two filter’s gratings, their relative position on the opposite window surfaces and the widths of the strips of both gratings to minimize light transmission on a specific date and time of day for a given latitude and longitude of the building and azimuth of the window. A meth-od has been developed for calculating the diffraction at the input and output gratings of the filter with regard for a complex movement of the Sun relative to the window and a corresponding change in the incidence angle of the solar beams on the gratings. To evaluate a decrease in the light transmittance of the filter due to diffraction, an additional factor is introduced into the calcu-lation equation. Geometric parameters of the filters and diffraction are calculated. The values of the diffraction factor are 0.9999992 and 0.9999998 for single or double glazed windows, respec-tively, i.e., the influence of diffraction on the light transmittance of the grating filter can be ne-glected.
Visual attention method based on vertex ranking of graphs by heterogeneous image attributes
Authors:   Murom Institute (branch), Vladimir State University named after Alexander and Nikolay Stoletovs, Zakharov A.A. , Titov D.V. ,   Southwest State University, Zhiznyakov A.L. ,   Murom Institute (branch), Vladimir State University named after Alexander and Nikolay Stoletovs, Titov V.S. ,   Southwest State University
Published: August 2020

The paper discusses a method of visual attention based on vertex ranking of graphs on the basis of image features. The aim of the research is to develop a method that allows high-precision detection of objects in images with low color contrast between the selected and background areas. The image is pre-segmented into regions to calculate the saliency map. The graph is based on regions. Each region is associated with related regions, as well as with areas adjacent to adjacent regions. The regions are vertices of the graph. The vertices of the graph are ranked according to the characteristics of the corresponding image areas. The scope is highlighted based on requests from background areas. The saliency map is determined based on background area queries. Regions adjacent to the edges of the image belong to the background areas. Color features of the image were used in the existing approach of visual attention based on the manifold ranking. Texture features and shape features are additionally used in the proposed method to improve accuracy. Gabor's energy function is used to calculate texture features. The distance between centers of the regions is calculated by analyzing the form. The proposed method has shown good results for detecting objects in images in which the background color and object color are in similar ranges. The experimental results are presented on test images. Precision-recall curves showing the advantage of the developed method are constructed.
Motor imagery recognition in electroencephalograms using convolutional neural networks
Authors:   National Research Tomsk Polytechnic University, Bragin A.D. , Spitsyn V.G. ,   National Research Tomsk Polytechnic University,   National Research Tomsk State University
Published: August 2020

Electroencephalography is a widespread method to record brain signals with the use of electrodes located on the surface of the head. This method of recording the brain activity has become popular because it is relatively cheap, compact, and does not require implanting the electrodes directly into the brain. The article is devoted to a problem of recognition of motor imagery by electroencephalogram signals. The nature of such signals is complex. Characteristics of electroencephalograms are individual for every person, also depending on their age and mental state, as well as the presence of noise and interference. The multitude of these parameters should be taken into account when analyzing encephalograms. Artificial neural networks are a good tool for solving this class of problems. Their application allows combining the tasks of extracting, selecting and classifying features in one signal processing unit. Electroencephalograms are time signals and we note that Gramian Angular Fields and Markov Transition Field transforms are used to represent time series in the form of images. The article shows the possibility of using the Gramian Angular Fields and Markov Transition Field transformations of the electroencephalogram (EEG) signal for motor imagery recognition using examples of imaginary movements with the right and left hand, also studying the effect of the resolution of Gramian Angular Fields and Markov Transition Field images on the classification accuracy. The best classification accuracy of the EEG signal into the motion and state-of-rest classes is about 99%. In future, the research results can be applied in constructing the brain-computer interface.
Method for camera motion parameter estimation from a small number of corresponding points using quaternions
Authors:   Samara National Research University, Goshin Ye.V. , Kotov A.P. ,   Samara National Research University,   IPSI RAS – Branch of the FSRC “Crystallography and Photonics” RAS
Published: August 2020

In this paper, we study methods for determining parameters of camera movement from a set of corresponding points. Unlike the traditional approach, the corresponding points in this paper are not used to determine the fundamental matrix, but directly to determine motion parameters. In addition, in this work, we use a multi-angle image formation model based on the representation of three-dimensional images and motion parameters in the form of quaternions. We propose method for determining motion parameters, including the selection of the most noise-free matches using the RANSAC method. The study presents results of an experiment on the “Middlebury” and “ETH3D” test kits, which contains a set of images with known values of the motion parameters. Using a program written in Python, a comparative experiment was conducted to evaluate the accuracy and reliability of the estimates obtained using the proposed method under conditions of a small number of corresponding points and a shallow depth of the scene. In the course of experimental studies, it was shown that under the above-described conditions, the reliability of parameter determination using the proposed method significantly exceeds the reliability of traditional methods for estimating motion parameters based on the calculation of the fundamental matrix.
Parameterized interpolation for fusion of multidimensional signals of various resolutions
Authors:   Samara National Research University, Gashnikov M.V. ,   IPSI RAS – Branch of the FSRC “Crystallography and Photonics” RAS
Published: August 2020

Parameterized interpolation algorithms are adapted to fusion of multidimensional signals of various resolutions. Interpolating functions, switching rules for them and local features are specified, based on which the interpolating function is selected at each point of the signal. Parameterized interpolation algorithms are optimized based on minimizing the interpolation error. The recurrent interpolator optimization scheme is considered for the situation of inaccessibility of interpolated samples at the stage of setting up the interpolation procedure. Computational experiments are carried out to study the proposed interpolators for fusion of real multidimensional signals of various types. It is experimentally confirmed that the use of parameterized interpolators allows one to increase the accuracy of signal fusion.
Modification of blurred image matching method
Authors:   Samara National Research University, Paringer R.A. ,   IPSI RAS – Branch of the FSRC “Crystallography and Photonics” RAS, Donon Y. ,   Samara National Research University,   IPSI RAS – Branch of the FSRC “Crystallography and Photonics” RAS, Kupriyanov A.V. ,   Samara National Research University,   IPSI RAS - Branch of the FSRC “Crystallography and Photonics” RAS
Published: August 2020

The article proposes a modification of the Blurred Image Matching (BIM) method, a key point selection method in images, thus solving a problem of their accurate comparison. A new approach for blobs selection and comparison is proposed. The use of these modifications allows us to achieve an increase in the proportion of correctly matched pairs of images by 30.2% compared to the basic method when working with noisy data.
Algorithm for reconstructing complex coefficients of Laguerre–Gaussian modes from the intensity distribution of their coherent superposition
Authors:   IPSI RAS – Branch of the FSRC “Crystallography and Photonics” RAS, Volotovskiy S.G. , Karpeev S.V. ,   IPSI RAS – Branch of the FSRC "Crystallography and Photonics" RAS; Samara National Research University,   Samara National Research University, Khonina S.N. ,   IPSI RAS – Branch of the FSRC “Crystallography and Photonics” RAS,   Samara National Research University
Published: August 2020

In this paper, we consider a problem of reconstructing complex coefficients of the coherent su-perposition of Laguerre–Gaussian modes from the field intensity in a plane perpendicular to the propagation axis at a given distance using the Levenberg–Marquardt and Brent algorithm. The efficiency of using stage-by-stage optimization to restore complex coefficients of a superposition is demonstrated not only on model, but also on experimental intensity distributions. The algorithm can be used in optical information transmission through a turbulent atmosphere to process the received intensity distribution of the optical signal.
Achievements in the development of plasmonic waveguide sensors for measuring the refractive index
Authors:   IPSI RAS – Branch of the FSRC “Crystallography and Photonics” RAS, Kazanskiy N.L. ,   Samara National Research University, Butt M.A. ,   Samara National Research University, Degtyarev S.A. ,   IPSI RAS – Branch of the FSRC “Crystallography and Photonics” RAS,   Samara National Research University, Khonina S.N. ,   IPSI RAS – Branch of the FSRC “Crystallography and Photonics” RAS,   Samara National Research University
Published: August 2020

Optical sensors are widely used in the biomedical, chemical and food industries. They provide high sensitivity to changes in the refractive index of the environment due to a specific distribution of resonances across the field. The sensitivity of the sensor is highly dependent on its material and structure. In this review, we focused on the analysis of silicon waveguides as a promising component for optical sensor miniaturization, and plasmon refractive index sensors without fluorescent labeling. We presented the latest developments of special types of plasmon structures, such as metal-insulator-metal waveguides, and their application in refractive index sensors. We analyzed numerous types of plasmon waveguides, their geometry, materials and manufacturing processes, as well as possible energy losses. A discussion of the spectral characteristics of recently proposed refractive index sensors, with an emphasis on their sensitivity and quality indicators, is an important part of the review.
Determining The Anxiety And Anxiety Levels Of University Students In The COVID 19 Outbreak.
Authors: Çalık Mustafa
Published: August 2020

Objective

The outbreak of the 2019 novel coronavirus disease (COVID-19) caused considerable public health problems. Departing from the case of COVID-19, this paper aims to not only find out the psychological impacts of the changes in universities’ educational programs on undergraduate students in Turkey but also make a scientific contribution to determining what kinds of supports can be given to university students in other possible social catastrophes that could take place in any future time.

Material- Methods

1117 university students over the age of 17 from 23 universities  took part in this study by completing the online questionnaire we prepared on the Internet. The relationship between university students’ stress and anxiety levels and their age, gender and class year were examined.

Result

While average BAI scores of male students were 11.56, female students’ average BAI scores were 16.65. Average STAI-1 points of male and female students were 46,71 and 49,04, respectively. As a result, it was found that there were significant differences between BAI and STAI-1 scores of male and female students.(p<0.05)

Conclusion

''Our study found that more than two/three of the  university students suffered from anxiety symptoms during the COVID-19 outbreak.'. In this regard, it can said that university students should learn to deal with such mental and emotional problems as stress, anxiety and fear, which more likely require psychological and physical effort, by taking necessary measures during important social catastrophes such as Covid-19 outbreak.
Intrahepatic Pregnancy - A Rare Form Of Abdominal Pregnancy At Lira Regional Referral Hospital, Northern Uganda; A Case Report And Literature Review
Authors: Odur Andrew , Okello Tom Richard , Okii Richard , Obbo Olwenyi John Stephen , Pecorella Irene
Published: August 2020

Primary intra-hepatic pregnancy is an extremely rare condition. The purpose of this study was to report a case of 24-year-old Gravida 2 para 1+0 who presented at 35 weeks of amenorrhea, vaginal bleeding and mild right upper abdominal tenderness. Ultrasonography revealed a non-viable extra-uterine fetus located around the right upper part of the abdomen with a bulky uterus. At laparotomy was preferred and on finding a fetus free abdominal cavity and uterus, a macerated female baby was delivered from inside the liver with birth weight of 2.7kilogram. Placenta was left in situ and methotrexate given to hasten its resorption. Maternal outcome during the 18 days of intense follow up was uneventful. This case is a rare occurrence in our setting and it has diagnostic challenges in low resource settings like ours, however intra-hepatic pregnancy can grow to considerable size and weight.
Prevalence Of Hepatotoxicity In HIV-Positive, Tuberculosis And HIV+TB Co Infected Patients In Tertiary Care Hospitals , Sindh
Authors: Uqaili Arsalan Ahmed , Gurbakhshani Marvi , Shaikh Zahid Ali , Ansari Imdad Ali , Gurbakhshani Keenjhar
Published: August 2020

Hepatotoxicity is historically the 3rd most common reason for drug withdrawal and toxicity-related discontinuation of treatment. This study was aimed at determining the incidence and the onset of hepatotoxicity and at evaluating the relationship of some risk factors for hepatotoxicity among Human Immunodeﬁciency Virus- (HIV-) positive, tuberculosis (TB), and HIV/TB patients on treatment. This was a prospective follow-up study involving 125 participants from the HIV/AIDS and TB treatment centres in Tertiary Care hospital of Larkana and Sukkur, Sindh. These TB and HIV patients were initiated on RHEZ (R = Rifampicin, H = Isoniazid, E = Ethambutol, and P = Pyrazinamide) and TELE (efavirenz/tenofovir/lamivudine), respectively, and followed up for 12 weeks between September 2018 and November 2019. The levels of liver enzymes (transaminases, gamma- glutamyltransferase, alkaline phosphatase, and unconjugated/total bilirubin) were measured spectrophotometrically using serum. The Chi-squared (χ2) test was used to assess the association between risk factors and hepatotoxicity, while the Kaplan-Meier survival analysis with the log-rank test was used to determine the occurrence of hepatotoxicity in the diﬀerent groups. We followed the general study population for a total person time of 6580 person-days, with an incidence rate and cumulative incidence of 8 cases per 1000 person-days (53/6580 person-days) and 42.4% (53/125), respectively (95% conﬁdence interval), recorded after 12 weeks of follow-up of all the participants. The onset of hepatotoxicity in the total study population was statistically signiﬁcant (χ2 = 9:5334; p = 0:022979; CI = 95%), with the majority observed at week eight of follow-up. Also, the incidence rate and cumulative incidence of hepatotoxicity with respect to HIV/AIDS, TB, and HIV/TB patients, respectively, at 95% conﬁdence interval were: 8 cases per 1000 person-days (32/3843 person-days) and 32/76 (42.1%), 6 cases per 1000 person- days (12/1932 person-days) and 12/32 (37.5%), and 11 cases per 1000 person-days (9/805 person-days) and 9/17 (52.9%). This study shows that the incidence rate and cumulative incidence of hepatotoxicity in HIV/AIDS, TB, and HIV/TB patients on treatment were high . Also, it is very important to check these patients’ liver function especially within the ﬁrst 12 weeks of treatment.
Synthesis and Characterization of Some New 4-Methyl-5-Imidazole Carbaldehyde Derivatives
Authors: ORHAN Ersin , KÖSE Mahmut , ALKAN Demet , ÖZTÜRK Leyla
Published: August 2020

Imidazole is a common and important heterocyclic
fragment of many biologically important molecules. 5-imidazole-carbaldehydes
containing mono- (N-1) methyl (or aryl) analogs are commonly used as building
blocks in medical chemistry. In this study, starting from
4-methyl-1H-imidazole-5-carbaldehyde, the N-1 atom of the imidazole ring is
derived with different alkyl groups. In addition, both N atoms of the starting
imidazole-carbaldehyde were methylated to give
5-carbaldehyde-1,3,4-trimethyl-3-imidazolium salt. The salt which possess quite
reactive carbaldehyde group could be used as a precursor for synthesis of other
imidazolium derivatives. Furthermore, 4-methyl-5-imidazole carbaldehyde was
converted into the benzoxazole, benzothiazole and benzoimidazole by a two-step
reaction over the aldehyde group. These new compounds could display some
biological activities.
The role of myocardial perfusion imaging in the identification of the obstructive coronary artery lesions: a tertiary cardiology center experience
Authors: SAVAŞ Göktuğ , SÜZER ASLAN Melek , FIRAT Mehmet Fatih , TERZI Sait
Published: August 2020

Objectives: Because of the moderate accuracy of treadmill electrocardiogram and fear of a claim if a diagnosis is missed, cardiologists usually order Myocardial Perfusion Imaging (MPI) as a first-step test in most of patients with chest pain admitted to cardiology department. The performance of the MPI in diagnosing obstructive CAD depends on the population studied. Thus we aimed to assess the agreement between MPI and coronary angiography in the identification of the obstructive coronary lesion. Methods: A total of 231 patients who underwent MPI due to suspicion of coronary ischemia and had a coronary angiogram within the last three months were included in this retrospective study. MPI and coronary angiography findings were analyzed to weigh the performance of MPI in determining obstructive coronary lesion. Results: The mean age was 63.9 ± 8.9 years, 54.5% being males. MPI showed a sensitivity of 0.86 in determining patients who had a significant (> 70%) coronary lesion. While evaluating the ability of MPI to detect ischemia in the left ventricle region which is supplied by the lesioned vessel, the sensitivity was found to be; 60% in determining anterior ischemia associated with significant LAD lesion, 77.4% in determining inferior ischemia associated with significant RCA lesion, and 44.4% in determining lateral ischemia associated with significant CX lesion. Conclusions: Our findings have shown that MPI with visual assessment has 86% sensitivity for detecting significant coronary artery stenosis. However, the sensitivity of MPI in determining ischemia in the left ventricle region which is supplied by the lesioned coronary artery was found to be 44.4 to 77.4%.
Colour recognition using colour histogram feature extraction and K-nearest neighbour classifier
Authors: Bayraktar Rabia , Akgul Batur Alp , Bayram Kadir Sercan
Published: August 2020

K-nearest neighbours (KNN) is a widely used neural network and machine learning classification algorithm. Recently, it has been used in the neural network and digital image processing fields. In this study, the KNN classifier is used to distinguish 12 different colours. These colours are black, blue, brown, forest green, green, navy, orange, pink, red, violet, white and yellow. Using colour histogram feature extraction, which is one of the image processing techniques, the features that distinguish these colours are determined. These features increase the effectiveness of the KNN classifier. The training data consist of saved frames and the test data are obtained from the video camera in real-time. The video consists of consecutive frames. The frames are 100 × 70 in size. Each frame is tested with K = 3,5,7,9 and the obtained results are recorded. In general, the best results are obtained when used K = 5.

 

Keywords: KNN algorithm, classifier, application, neural network, image processing, developed, colour, dataset, colour recognition.
User behaviour analysis and churn prediction in ISP
Authors: Turkmen Ahmet , Bahcevan Cenk Anil , Alkhanafseh Youssef , Karabiyik Esra
Published: August 2020

There is no doubt that customer retention is vital for the service sector as companies’ revenue is significantly based on their customers’ financial returns. The prediction of customers who are at the risk of leaving a company’s services is not possible without using their connection details, support tickets and network traffic usage data. This paper demonstrates the importance of data mining and its outcome in the telecommunication area. The data in this paper are collected from different sources like Net Flow logs, call records and DNS query logs. These different types of data are aggregated together to decrease the missing information. Finally, machine learning algorithms are evaluated based on the customer dataset. The results of this study indicate that the gradient boosting algorithm performs better than other machine learning algorithms for this dataset.

 

Keywords: Data analysis, customer satisfaction, subscriber churn, machine learning, telecommunication.
Las zonas periurbanas de las grandes metrópolis, clave de las políticas de reinserción de naturaleza para mejorar el entorno de vida de los ciudadanos
Authors: Wiesztort Laurène
Published: August 2020

Las ciudades cada vez más densas sustituyen los espacios naturales y agrícolas por la extensión urbana. Por eso, los habitantes expresan un malestar. A raíz de esta constatación, en 1950 aparecen las primeras preguntas sobre las ciudades, que analizan como temas fundamentales el desarrollo sostenible y el calentamiento global con el objetivo de generar investigaciones para mejorar el entorno urbano, haciéndolas más sostenibles y habitables. Las conclusiones son alarmantes y es por esa razón que están surgiendo nuevas políticas públicas de reinserción de naturaleza en las ciudades, pero ¿cómo lograrlo en ciudades densas? ¿Qué tipo de naturaleza? ¿Para quién? ¿En qué formas? Así, el objetivo de este artículo es inventariar, observar y criticar estos grandes proyectos para responder a esta problemática. La metodología se construyó con análisis de literatura y conceptos, y trabajos de campo para comprender la evolución de las políticas, los proyectos y sus desafíos desde los años 1950. Abordaremos los conceptos de cinturones verdes y luego de infraestructuras verdes, tramas verdes y azules, lineales originalmente diseñados para convertirlos en parques en el corazón de las metrópolis. Por último, nos hemos interesado en proyectos recientes, en particular dos, para generar una crítica.