bluuebunny/crossref_metadata_2025 huggingface dataset:
Comparison of Machine Learning Algorithms for Processing of Health Insurance Claim
Authors:   Delhi Technological University, Delhi India, Saxena Paridhi , Seth Abhishek , Chawla Gangesh , Singari Ranganath
Published: May 2021

The health insurance industry protects against financial losses resulting from various health conditions. Since a long, it has relied on statistics and data to calculate risks and thereby, centre attention more profoundly on a particular target audience for increasing the operational efficiency of the industry. Technologies like Machine Learning and Artificial Intelligence prove to be an efficient tool for enabling insurance companies to predict the Customer Lifetime Value (CLV). This can be done using customer lifestyle behaviour data allowing to assess the customer's potential profitability for insurance companies. This creates a more personalised marketing offer within the audience. The insurance industry and its components constitute a dynamic and competitive sector representing approximately 2.7 percent of the US Gross Domestic Product (GDP). As customers have become progressively scrupulous about narrowing down their specific requirements, insurers and insurance companies are scrutinizing techniques for improving business operations and consumer satisfaction. An attempt in this regard has been made to analyse the “sample insurance claim prediction dataset" using various machine learning models including Decision tree, Random Forest algorithms, Naïve Bayes, K-nearest neighbour algorithm, Supper Vector machines and Neural Networks. A comparative analysis is performed to generate reports.
Handle Design of Woodworking Tools: Preferences and Recommendations of Craftsmen and Design Students
Authors:   Industrial Design Department, National Institute of Technology Rourkela, India, Bisht Dhananjay Singh , Khan Mohammed Rajik
Published: May 2021

23 popular woodworking tool handle designs were collected to develop a reference visual catalog. Survey data was collected from 19 male craftsmen (11 carvers, 8 carpenters) regarding their most frequently used tools along with recommendations on handle designs suitable for these tools. Opinions were also collected regarding the most “liked” and “disliked” handle designs on the catalog. Subjective preferences and recommendations of handle designs for the most frequently used tools were also collected from a group of 58 undergraduate students of Design (41 male, 17 female). Participant responses revealed that woodcarvers most "liked” an ivory-colored, Japanese style, circular cross-section, regular-sized handle with a hooped top. Carpenters most "liked" a wenge-colored, rectangular-sectioned bulky handle with a hooped top. Male Design students most "liked" a golden-honey-colored, London pattern handle with an octagonal central section and domed wooden top. Female Design students most "liked" a beech-colored, bulky pear-shaped round handle with a hooped top. Overall, 12 different tools which included different sizes of u-gouges, v-parting tools, fishtail-chisels, firmer-chisels, mortise-chisels, and an in-denting tool were found to be the most frequently used implements by the craftsmen. On an aggregate for these 12 tools, an espresso-colored, bulky pear-shaped round handle with a hooped top was found to be the most recommended handle and a Bubinga-colored elongated pattern maker type handle was the least recommended handle. Results from this paper should help researchers and manufacturers gain qualitative insights into subjective preferences and biases that may exist for and against certain handle design features in the context of woodworking tool research and development
Effect of Heat Treatment Processes on Metals and Alloys-A Review
Authors:   Delhi Institute of Tool Engineering, Okhla, Delhi-110020, India, Bharti Sheel , Arora Gaurav , Singh Kanwarjeet , Varshney Swati
Published: May 2021

Heat treatment can be simply defined as heating, holding, and cooling of materials. The current review paper presents the various types of heat treatment processes done on the different metals and alloys. A comparative analysis of the effect of heat treatment on hard-ness, yield strength, and microstructure, etc. of the various metals and alloys has been presented in this paper. The literature has shown that the heat treatment resulted in the development of new phases along with the improvement of microstructural and mechanical properties of various metals and alloys. The paper also represents the consequence of microwave heat treatment done on various substrates. The final part of the paper discusses the suggested future work that can be done.
Biomechanical details regarding the efficiency of start in sprinting events
Authors: Petrescu Tomina Dana , Ionescu Bondoc Dragoș
Published: May 2021

Our research is based on a study on the efficiency of athletic start in sprinting events, based on biomechanical analyses of the “key” moments from the start of a sprinter, component of the national athletic team. The study wishes to highlight a number of important details that, under the most favorable conditions, would allow the athlete a better use of the available potential at the start. The research was based on high-frequency footage recordings of a top runner who rankedthird at the National Athletics Indoor Championships. After analyzing and interpreting the main sequence of the phases of each step after running out of the starting blocks, some technical aspects have been highlighted, which have proved to be restrictive on the performance of the athlete in the competition.These minor technical errors highlighted in our research may be considered to have made the difference between our subject and the winner of the competition.We believe that by remedying these small technical deficiencies, through specific analytical exercises, the value of performance of our subject can be substantially improved. The paper is an analysis of the moments of completion of pulses on the first steps of detachment from the starting block and the moments in which the contact is made with the runway after each phase of flight. For each of these moments, the impulse angles of the first steps and their growth rate were analyzed, the ground contact angles at landing after each flight phase.
Comparative study regarding the level of anxiety in various categories of athletes
Authors: Ababei Catalina
Published: May 2021

The Romanian Language Dictionary (2009) defines anxiety as inquietude, unrest, fear. The athletes' emotional states can change easily, especially in less experienced athletes, often near acompetition that demands reaching a goal, or when they find themselves in new situations. This can cause them to block or have no reaction in key moments. Professional sports regard anxietyas a normal reaction of the athlete's body, believing that in this manner it adapts to new conditions and functional parameters. The study was based on the hypothesis stating that anxietycould have various levels in athletes before a competition, according to their sport. The research was conducted on 45 athletes practicing wrestling, track and field, and boxing at a national level, for various Bacau sports clubs. The main research method for this study was the inquiry, and the working instrument was the questionnaire - J. Taylor's anxiety scale.
AGGLUTINATED CONICAL FORAMINIFERA (ORBITOLINIDAE, COSKINOLINIDAE) FROM THE UPPER CRETACEOUS (CAMPANIAN) OF GREECE, WITH DESCRIPTION OF PARACOSKINOLINA KLOKOVAENSIS N. SP.
Authors: SCHLAGINTWEIT FELIX
Published: May 2021

An assemblage of agglutinated conical foraminifera including Lepinoconus chiocchinii Cruz-Abad et al., Calveziconus lecalvezae Caus & Cornella, Paleodictyoconus sp., and Paracoskinolina klokovaensis n. sp. are described from the upper lower-middle Campanian of Klokova Mountain of the Gavrovo-Tripolitza Zone, SW continental Greece. With the presence of one rafter in the marginal zone, the new species P. klokovaensis compares to the Lower Cretaceous species Paracoskinolina arcuata (Arnaud-Vanneau) that is distinguished by its cylindroconical test morphology and much larger size. The assemblage occurs in inner platform carbonates associated with other foraminifers such as dicyclinids, and Accordiella conica Farinacci. Representatives of the genus Paracoskinolina were so far only reliably reported from the Upper Berriasian–Albian interval. This new record suggests that the genus either survived the larger benthic foraminifera extinction event associated with the Cenomanian – Turonian boundary anoxic event, or may be an example of an Elvis taxon or homoplasy.
A RELIABILITY TEST METHOD FOR AGRICULTURAL PADDY FIELD INTELLIGENT ROBOT
Authors: Xuefeng Deng , Bingqian Zhou , Yiming Hou
Published: May 2021

With the development of artificial intelligence technology, in order to alleviate the labour intensity of agricultural paddy field production and improve production efficiency, the development of robot used in paddy field production has been a hot research in the field of agricultural production. Different from the industrial environment, the agricultural production environment is complex, and there are many interference factors to the intelligent robot. Therefore, ensuring the reliability of the robot in the operation has become an important index in the production process. The model checking technique can evaluate the reliability of the system when designing the system. In this paper, timed automata is used to model the agricultural paddy field intelligent robot, and the environmental influence factor model is introduced, so as to evaluate the reliability of the system qualitatively and quantitatively in the design of the agricultural paddy field robot. Finally, the control prediction of the system safety is carried out, and to provide a definite basis for the actual engineering design.
CHEMICAL VALORIZATION OF CELLULOSE FROM LIGNOCELLULOSIC BIOMASS: A STEP TOWARDS SUSTAINABLE DEVELOPMENT
Authors: KAUR RAMANDEEP , KAUR PUNEET
Published: May 2021

"The potential of non-edible lignocellulosic biomass paves the path to sustainable economy. A large number of valueadded products have been synthesized by the fractionation of the major components of biomass, i.e. cellulose, hemicelluloses and lignin. Cellulose, the most abundant biopolymer on earth, serves as a starting material for the synthesis of various platform chemicals, such as sorbitol, 5- hydroxylmethylfurfural (HMF), dimethylfuran and levulinic acid. Hydrogels and aerogels fabricated from cellulose, modified cellulose or nanocellulose have proved valuable in a wide range of such as biomedical, food and technological applications. Cellulose-based polymers or bioplastics also emerged as an alternative to fossil fuel-based polymers. In this review, chemical paths to valorize plant cellulose for producing various value-added products have been discussed. The major challenge for valorization is the development of novel and green synthesis methods with simultaneous focus on an integrated approach."
THERMAL DECOMPOSITION OF WOOD FIBERS: THERMAL SIMULATION USING THE F-TEST STATISTICAL TOOL
Authors: ORNAGHI HEITOR L. , ORNAGHI FELIPE GUSTAVO , MOTTA NEVES ROBERTA , MAGALHÃES DE OLIVEIRA DANIEL , POLETTO MATHEUS
Published: May 2021

"Wood biomass is an alternative for fossil fuels to produce bioenergy, due to its low cost, renewability and
environmental friendliness. In order to use biomass as an energy source, understanding its thermal degradation behavior
is highly recommended. This work focuses on the thermal degradation of wood fibers belonging to different species
(Pinus elliotti (PIE), Eucalyptus grandis (EUG) and Mezilaurus itauba (ITA)), commonly used by the Brazilian lumber
industry. The prediction of their degradation kinetics and overall thermal behavior was performed based on the most
common theoretical data using the F-test statistical tool. The most probable degradation mechanism was found to be
autocatalytic for all the wood fibers tested, with three different degradation steps. The results obtained were in
accordance with the findings recently reported in the literature using other fitting methods. It was found that cellulose is
the major contributor to Arrhenius parameters, while hemicelluloses – to reaction order."
Fast tunable all-polarization-maintaining supercontinuum fiber laser for CARS microscopy
Authors: Yang Kangwen , Huo Lizhong , Ao Jianpeng , Wang Qingting , Hao Qiang , Yan Ming , Huang Kun , Ji Minbiao , Zeng Heping
Published: May 2021

We have demonstrated a compact fiber laser with broad and fast wavelength tunability for coherent anti-Stokes Raman scattering (CARS) microscopy. Originated from an Er-doped fiber laser, the Stokes pulses can be tuned from 1015 to 1060 nm within 300 μs from supercontinuum of a tapered high nonlinear fiber, while pump pulses at 790 nm were obtained by second harmonic generation. The two beams were then sent to microscopes for CARS detection of oil, ethanol and mouse ear samples. This fast and broadly tunable fiber laser in the all-polarization-maintaining architecture would be promising to implement rapid label-free histology in clinical translation.
Precipitation Nowcasting using Data-driven Reduced-order Model
Authors: Vidyadharan Divya S , Xavier Aaron , Bastian Blossom Treesa , Ragh Ajay , Chittilapilly Naveen
Published: May 2021

Radar-based precipitation nowcasting refers to predicting rain for a short period of time using radar reflectivity images. For dynamic nowcasting, motion fields can be extrapolated using an approximate and localized reduced-order model. Motion field estimation based on traditional Horn-Schunck (HS) algorithm suffers from over-smoothing at discontinuities in non-rigid and dissolving texture present in precipitation nowcasting products. An attempt to preserve the discontinuities using an L1 norm formulation in HS led to the use of Total Variation L1 norm (TVL1). In this paper, we propose a radar-based precipitation nowcasting model with TVL1-based estimation of motion field and Sparse Identification of Non-linear Dynamics (SINDy)-based

estimation of non-linear dynamics. TVL1 is effective in preserving the edges especially in the case of the eye of typhoons and squall lines while estimating motion vectors. SINDy captures the non-linear dynamics and generates the subsequent update values for the motion field based on a reduced-order representation. Finally, the SINDy-generated ensemble of motion field is used along with

the radar reflectivity image for generating precipitation nowcasts. We evaluated the effectiveness of TVL1 in preserving edges while capturing the motion field from non-rigid surfaces. The performance of the proposed TVL1-SINDy model in nowcasting weather events such as Typhoons and Squall lines are evaluated using performance metrics such as Mean Absolute Error (MAE), and Critical Success Index (CSI). Experimental results show that the proposed nowcasting system demonstrates better performance compared to the benchmark nowcasting models with lower MAE, higher CSI at higher lead times.
Adaptive Kalman Filter for Linear Systems with Additive and Multiplicative Noises
Authors: Yu Xingkai
Published: May 2021

This manuscript investigates adaptive Kalman filter problem of of linear systems with multiplicative and additive noises. The main contributions are stated in two aspects.

Firstly, compared with the estimation problem of linear systems with additive noises, we propose an algorithm that is applicable to the linear systems with both additive and multiplicative noises. To solve the technical issue raised by the multiplicative noise, a variational Bayesian approach is proposed. Moreover, the proposed approach is capable of estimating the multiplicative and additive measurement noise covariances as a whole, while the existing algorithms often operate in a separate way.

Secondly, in contrast with existing literature, where the covariance of the multiplicative noise is assumed to be fixed and known, we focus on the situation that the covariances of both additive and multiplicative noises are time-varying and unknown. Towards this end, a novel adaptive Kalman filter is proposed to jointly estimate the covariances of multiplicative and additive noises based on projection formula and a VB approach.
Geometry of Multiprimary Display Colors I: Gamut and Color Control
Authors: Sharma Gaurav , Rodriguez-Pardo Carlos
Published: May 2021

Displays that render colors using combinations of more than three lights are referred to as multiprimary displays. For multiprimary displays, the gamut, i.e., the range of colors that can be rendered using additive combinations of an arbitrary number of light sources (primaries) with modulated intensities, is known to be a zonotope, which is a specific type of convex polytope. Under the specific three-dimensional setting relevant for color representation and the constraint of physically meaningful nonnegative primaries, we develop a complete, cohesive, and directly usable mathematical characterization of the geometry of the multiprimary gamut zonotope that immediately identifies the surface facets, edges, and vertices and provides a parallelepiped tiling of the gamut. We relate the parallelepiped tilings of the gamut, that arise naturally in our characterization, to the flexibility in color control afforded by displays with more than four primaries, a relation that is further analyzed and completed in a Part II companion paper. We demonstrate several applications of the geometric representations we develop and highlight how the paper advances theory required for multiprimary display modeling, design, and color management and provides an integrated view of past work on on these topics. Additionally, we highlight how our work on gamut representations connects with and furthers the study of three-dimensional zonotopes in geometry.
Lifecycle Optimization of Smart Contract for Flexibility
Authors: Su Hong
Published: May 2021

Smart contract-based methods are used to implement the blockchain applications. While smart contracts have separate pre-deployed steps, which are suitable for applications that are deployed once and invoked many times. However, there are smart contracts that are used only one time (the disposable smart contract) or few times. Pre-deployment requires an additional step and additional transactions, which bring burdens (such as longer waiting time and more transaction fees) to users. In this paper, we propose a new Lifecycle model of smart contracts, which allows combining the pre-deployment with function invocations. This facilitates the usage of the disposable smart contract, as users are only required to send one transaction to perform both the pre-deployment and the function invocation. Together with the smart contract separation, it also allows participants to customize their special smart contracts at the request time. At last, we verify the proposed model and it shows the potential to save additional burden and to facilitate the usage of the smart contract.
PLANT COMMUNITIES OF BROAD-LEAVED FORESTS OF THE COLCHIS LOWLAND (WESTERN TRANSCAUCASIA)
Authors: Ermakov N. B. , Plugatar Yu. V. , LeiЬa V. D. , Ermakova E. V.
Published: May 2021

Three associations of the class Carpino-Fagetea Jakucs et Passarge 1968 were described as а result of the classification of forest communities of the Colchis Lowland (Westem Transcaucasia) using the Brown­ Blanquet method. Association Vaccinio arctostaphilli-Carpinetum betuli ass. nova prov. was included in the order Lathyro-Carpinetalia Passarge 1981, alliance Crataego-Carpinion Passarge 1981. Associations Truello thunbergii-Alnetum barbatae ass. nova prov. and Carici remotae-Pterocmyetum pterocarpae ass. nova prov. were included in the order Rhododendro ponticae-Fagetalia orientalis Quezel et al. 1992, alliance Alnion barbatae Quezel et al. 1992. The results of the DCA ordination and the interpretation of the leading axes demonstrated three well-distinguished ecological and floristic types of deciduous forests (ofthe association rank) forming the ecological series according to the leading ecological factors - the degree of humidity of habitats and the degree of drainage of substrates. Twenty-three plant species - thermophilous Tertiary rehcs were found in all three associations. Of these, eight evergreen species play а significant phytocoenotic role in the formation of the understory in forest communities.The pecuharities of the Tertiary rehc speciesdistributions in the floristic compositions of described associations are discussed.
ENZYMATIC ACTIVITY OF POST-PYROGENIC SOILS OFTHE UTRISH RESERVE
Authors: Vilkova V. V. , Кazeev K. S. , Shabunina V. V. , Kolesnikov S. I.
Published: May 2021

Southem Federal University, Academy ofBiology and Biotechnology, Rostov-on-Don, Russia. А study of the enzyme activity of soils in two sites of the Abraus Peninsula in the coastal part of the Utrish reserve was conducted. Sites differ in the period of post-fire recovery. The long-term significant influence of fires on the enzyme activity (catalase, invertase, peroxidase, urease) of brown subtropical soils (Chromic Cambisols) is shown. The activity of various enzymes of soils is reduced compared to the soils of the control sites. The degree of inactivation of enzymes depends on the type of enzyme and the time of post-pyrogenic recovery of ecosystems.
A ordem social na teoria de Max Weber
Authors: Dos Santos Bolda Bruna
Published: May 2021

Os estudos atualizativos dos escritos de Max Weber questionam seu estatuto de “individualista metodológico”. Perseguindo esses esforços antirreducionistas, visualizamos em seus escritos metodológicos (nomeadamente, Kategorien de 1913 e Grundbegriffe de 1921) uma a macrossociologia das ordens sociais – que será objeto de discussão neste estudo. Em termos formais, em ambos os textos Weber concebe a ordem como o ápice do nível macro. Em termos substantivos, todavia, enquanto em 1913 a ordem é exposta como uma regulamentação da relação social que possui validade formal, em 1921, ao inserir o elemento moral-normativo da vigência legítima, a ordem é descrita como um conjunto de deveres considerados máximas obrigatórias para as ações. Quer dizer,  Weber deixa de pensar a ordem somente em função do direito (ordem estabelecida) e passa a articular seu raciocínio a partir da política (ordem legítima).
A escrita de mulheres como espaço de elaboração de traumas coletivos
Authors: Saraiva Junia Saraiva
Published: May 2021

O presente artigo se propõe a analisar a escrita literária das obras Meio Sol Amarelo (2008) de Chimamanda Ngozi Adichie e Baratas (2018) de Sholastique Mukasonga, considerando que as obras fornecem o espaço terapêutico necessário para que os traumas provenientes de guerras e genocídios em seus países possam ser elaborados. Dessa forma, a escrita das autoras, além de resgatar a história perdida de Ruanda e da Nigéria, permitem a elaboração necessária para que as sociedades que foram construídas em um sistema baseado na violência possam superar a repetição de atos violentos, conforme aponta Sigmund Freud em sua obra Recordar, repetir e elaborar (1914/1911-1913). Além disso, consideramos que a escrita das autoras, retratam as vozes dos que foram duplamente silenciados, no que diz respeito ao silêncio imposto para seu gênero e para sua etnia, o que confere as obras uma dupla potência e significação.
HUBUNGAN TUGAS PMO DALAM MENGINGATKAN PERIKSA DAHAK DENGAN KEJADIAN DROP OUT (DO) PENGOBATAN TUBERKULOSIS
Authors: Sari Nina Pamela , Nugraha Gandi Sukma
Published: May 2021

Latar belakang: Tuberculosis (TB) sampai saat ini masih menjadi masalah utama kesehatan didunia. Dalam program pemberantasan penyakit TB masih adanya kejadian drop out (DO)pengobatan TB. TB di Indonesia menjadi penyebab kematian nomor dua setelah stroke. Angkakematian akibat TB dipengaruhi oleh gagalnya pengobatan atau DO. Tugas PMO selainmendampingi pasien menjalani pengobatan TB juga mengingatkan periksa dahak sebagaipengawasan perkembangan pengobatan pasien TB.Tujuan penelitian ini adalah untuk mengetahui pelaksanaan tugas PMO (Pengawas MenelanObat) dalam mengingatkan periksa dahak dengan kejadian drop out (DO) pengobatan TB diwilayah kerja puskesmas Tamansari Kota Tasikmalaya.Metode penelitian : metode analitik menggunakan rancangan retrospektif dengan pendekatancase control. Populasi terdiri dari populasi kasus yaitu penderita TB yang DO dan populasikontrol yaitu penderita TB yang tidak DO. Sampel yang diambil terdiri dari sampel kasus 56orang dan sampel kontrol 56 orang diperoleh dengan menggunakan teknik simple randomsampling. Instrumen yang digunakan adalah kuesioner. Data yang diperoleh dalam penelitian inidianalisis uji Chi Square dengan p value 0,05 dan menghitung nilai Odds Ratio (OR).Hasil : Dari hasil penelitian dapat disimpulkan bahwa faktor pelaksanaan tugas PMO dalammengingatkan periksa dahak berhubungan signifikan dengan DO pengobatan TB. (pvalue=0.018, OR=2.600). Saran : Berdasar hasil penelitian ini diharapkan dapat sebagai dasarpeningkatan kinerja dari petugas programer TB dan PMO dalam meningkatkan kesadaranpenderita TB dalam kepatuhan pengobatan.
Estimation of hydromechanical parameters of limb lymphedematous tissue with the use of chamber tests
Authors: Kaczmarek Mariusz , Nowak Joanna , Olszewski Waldemar L. , Zaleska Marzanna
Published: May 2021

Purpose: In this paper, in vivo methods of estimation of the shear modulus and hydraulic permeability of subcutaneous tissue of lower limb are presented. Methods: The experimental technique is based on single- or two-chamber inflation-deflation tests in which temporal changes in limb circumference under the test chamber for cyclic loading are registered. Simplified models for fast undrained deformation and slow creep of oedematous tissue with squeezing out interstitial liquid were considered. Finite element simulations of the chamber test within a finite deformation poroelastic model were elaborated. Results: Formulas necessary to estimate the shear modulus and permeability of subcutaneous tissue were derived and then tested or calibrated using the results of poroelastic simulations. An example of application of the derived formulas for clinical data obtained from the chamber test was discussed. Conclusions: A simple in vivo methods of estimation of the hydromechanical properties of lymphedematous tissue (shear modulus and permeability) were proposed. The strengths and weaknesses of the proposed methodology were discussed.
Design and development of an e-nose system for the diagnosis of pulmonary diseases
Authors: Binson V.A. , Subramoniam M.
Published: May 2021

Purpose: The aim of this paper was to discuss the design and development of an innovative e-nose system which can detect respiratory ailments by detecting the Volatile Organic Compounds (VOCs) in the expelled breath. In addition to nitrogen, oxygen, and carbon dioxide, the expelled breath contains several VOCs, some of which are indicative of lung-related conditions and can differentiate healthy controls from people affected with pulmonary diseases. Methods: This work detailed the sensor selection process, the assembly of the sensors into a sensor array, the design and implementation of the circuit, sampling methods, and an algorithm for data analysis. The clinical feasibility of the system was checked in 27 lung cancer patients, 22 chronic obstructive pulmonary disease (COPD) patients, and 39 healthy controls including smokers and non-smokers. Results: The classification model developed using the support vector machine (SVM) was able to provide accuracy, sensitivity, and specificity of 88.79, 89.58 and 88.23%, respectively for lung cancer, and 78.70, 72.50 and 82.35%, respectively for COPD. Conclusions: The sensor array system developed with TGS gas sensors was non-invasive, low cost, and gave a rapid response. It has been demonstrated that the VOC profiles of patients with pulmonary diseases and healthy controls are different, hence, the e-nose system can be used as a potential diagnostic device for patients with lung diseases.
The influence of facet joint orientation in the lumbar spine segment on the intervertebral disc bulge
Authors: Szkoda-Poliszuk Klaudia , Żak Małgorzata
Published: May 2021

Purpose: Due to the growing percentage of degenerative spinal diseases among the population, it is extremely important to assess how the orientation of the articular facets affects the changes in the intervertebral disc. Therefore, the aim of this study was to assess the effect of the orientation of the articular facets on the changes occurring in individual layers of the annulus fibrosus of the intervertebral disc under the influence of the load causing extension. Methods: Numerical simulations were performed for five configurations of the functional spinal units: physiological, with moderate tropism, severe tropism, and segments in which non-physiological orientation was modelled of both processes with different ranges. Results: It can be concluded that severe tropism causes more significant changes in intervertebral disc bulging on the physiological side of the orientation of the articular facets. Furthermore, the value of stress on articular processes increases tenfold on the side of severe tropism compared to the physiological facet joint orientation. Conclusion: Facet joint orientation plays an important role in the transfer of loads by the spine and the posterior column provides important support for the spine during extension.
On approximating curves associated with nonexpansive mappings
Authors:   DIPARTIMENTO DI MATEMATICA E INFORMATICA UNIVERSITA DEGLI STUDI DI PALERMO VIA ARCHIRAFI 34, 90123 PALERMO, ITALY E-mail address: fvetro@math.unipa.it, VETRO FRANCESCA
Published: May 2021

Let X be a Banach space with metric d. Let T, N : X → X be a strict d-contraction and a d-nonexpansive map, respectively. In this paper we investigate the properties of the approximating curve associated with T and N. Moreover, following [3], we consider the approximating curve associated with a holomorphic map f : B → α B and a ρ-nonexpansive map M : B → B, where B is the open unit ball of a complex Hilbert space H, ρ is the hyperbolic metric defined on B and 0 ≤ α < 1. We give conditions on f and M for this curve to be injective, and we show that this curve is continuous.
On a regularization technique for Kovarik-like approximate orthogonalization algorithms
Authors:   FACULTY OF MATHEMATICS AND COMPUTER SCIENCE OVIDIUS UNIVERSITY 900527, CONSTANTA, ROMANIA E-mail address: anicola@univ-ovidius.ro, NICOLA AURELIAN , POPA CONSTANTIN ,   FACULTY OF MATHEMATICS AND COMPUTER SCIENCE OVIDIUS UNIVERSITY 900527, CONSTANTA, ROMANIA E-mail address: cpopa@univ-ovidius.ro, RUDE ULRICH ,   INSTITUTE FOR COMPUTER SCIENCE 10 (SYSTEMSIMULATION), FRIEDRICH-ALEXANDER-UNIVERSITAT ERLANGEN-NURNBERG, GERMANY E-mail address: ulrich.ruede@informatik.uni-erlangen.de
Published: May 2021

In this paper we consider four versions of Kovarik’s iterative orthogonalization algorithm, for approximating the minimal norm solution of symmetric least squares problems. Although the theoretical convergence rate of these algorithms is at least linear, in practical applications we observed that a too big number of iterations can dramatically deteriorate the already obtained approximation. In this respect we analyse the above mentioned Kovarik-like methods according to the modifications they make on the “machine zero” eigenvalues of the problem’s (symmetric) matrix. We establish a theoretical almost optimal formula for the number of iterations necessary to obtain an enough accurate approximation, as well as to avoid the above mentioned troubles. Experiments on collocation discretization of a Fredholm first kind integral equation illustrate the efficiency of our considerations.
Sufficient conditions for the existence of some nonoscillatory solutions of third-order nonlinear differential equations
Authors:   INSTITUTE OF MATHEMATICS FACULTY OF SCIENCE, P. J. SAFARIK UNIVERSITY JESENNA 5, 040 01 KOSICE, SLOVAK REPUBLIC E-mail address: ivan.mojsej@upjs.sk, MOJSEJ IVAN , TARTALOVA ALENA ,   INSTITUTE OF MATHEMATICS FACULTY OF SCIENCE, P. J. SAFARIK UNIVERSITY JESENNA 5, 040 01 KOSICE, SLOVAK REPUBLIC E-mail address: alena.tartalova@tuke.sk
Published: May 2021

The aim of this paper is to study the asymptotic behavior of solutions of nonlinear differential equations of the third-order with quasiderivatives. In particular, we state the sufficient conditions ensuring the existence of some nonoscillatory solutions with a specified asymptotic property as t tends to infinity. The basic tool used in proving our results is the classical Banach contraction mapping principle.
Boundary value problems for nonlinear systems with generalized second-order differences
Authors:   GH. ASACHI TECHNICAL UNIVERSITY DEPARTMENT OF MATHEMATICS CAROL I 11, 700506, IASI, ROMANIA E-mail address: rluca@math.tuiasi.ro, LUCA RODICA
Published: May 2021

In a real Hilbert space, we investigate the existence and uniqueness of the solutions for two classes of infinite nonlinear systems with generalized second-order differences, one of them subject to a boundary condition. Some applications to nonlinear differential systems with monotone operators are also presented.
Some applications of CHEVIE to the theory of algebraic groups
Authors:   INSTITUTE OF MATHEMATICS UNIVERSITY OF ABERDEEN ABERDEEN AB24 3UE, UK E-mail address: m.geck@abdn.ac.uk, GECK MEINOLF
Published: May 2021

The computer algebra system CHEVIE is designed to facilitate computations with various combinatorial structures arising in Lie theory, like finite Coxeter groups and Hecke algebras. We discuss some recent examples where CHEVIE has been helpful in the theory of algebraic groups, in questions related to unipotent classes, the Springer correspondence and Lusztig families.
Positive periodic solutions for systems of second order differential equations
Authors:   TECHNICAL UNIVERSITY OF CLUJ-NAPOCA DEPARTMENT OF MATHEMATICS C. DAICOVICIU 15, 400020 CLUJ-NAPOCA, ROMANIA E-mail address: Vasile.Dincuta@math.utcluj.ro, DINCUTA-TANASE VASILE
Published: May 2021

In this paper we seek for positive periodic solutions for a system of second order differential equations using a vector version of Krasnoselskii’s Fixed Point Theorem in Cones. This makes possible that the nonlinear term of the system have different behaviors both in components and variables.
Generalized Weyl’s theorems for polaroid operators
Authors:   DEPARTMENT OF MATHEMATICS UNIVERSIDAD DE ORIENTE NUCLEO DE SUCRE UNIVERSITY CUMANA, VENEZUELA E-mail address: carpintero.carlos@gmail.com, CARPINTERO C. , MUNOZ D. ,   DEPARTMENT OF MATHEMATICS UNIVERSIDAD DE ORIENTE NUCLEO DE SUCRE UNIVERSITY CUMANA, VENEZUELA E-mail address: dmunoz@sucre.udo.edu.ve, ROSAS E. ,   DEPARTMENT OF MATHEMATICS UNIVERSIDAD DE ORIENTE NUCLEO DE SUCRE UNIVERSITY CUMANA, VENEZUELA E-mail address: ennisrafael@gmail.com, GARCIA O. ,   DEPARTMENT OF MATHEMATICS UNIVERSIDAD DE ORIENTE NUCLEO DE SUCRE UNIVERSITY CUMANA, VENEZUELA DEPARTMENT OF MATHEMATICS UNIVERSIDAD DE ORIENTE. NUCLEO DE ´ SUCRE UNIVERSITY CUMANA, VENEZUELA E-mail address: ogarcia@sucre.udo.edu.ve, SANABRIA J. ,   DEPARTMENT OF MATHEMATICS UNIVERSIDAD DE ORIENTE NUCLEO DE SUCRE UNIVERSITY CUMANA, VENEZUELA E-mail address: jsanabri@sucre.udo.edu.ve
Published: May 2021

In this paper we establish necessary and sufficient conditions on bounded linear operators for which generalized Weyl’s theorem, or generalized a-Weyl theorem, holds. We also consider generalized Weyl’s theorems in the framework of polaroid operators and obtain improvements of some results recently established in [20] and [29].
On a second order differential equation with piecewise constant mixed arguments
Authors:   ANKARA UNIVERSITY DEPARTMENT OF MATHEMATICS 06100, ANKARA, TURKEY E-mail address: bereket@science.ankara.edu.tr, BEREKETOGLU H. , SEYHAN G. ,   ANKARA UNIVERSITY DEPARTMENT OF MATHEMATICS 06100, ANKARA, TURKEY E-mail address: gseyhan@science.ankara.edu.tr, KARAKOC F. ,   ANKARA UNIVERSITY DEPARTMENT OF MATHEMATICS 06100, ANKARA, TURKEY E-mail address: karakoc@science.ankara.edu.tr
Published: May 2021

We prove the existence and uniqueness of solutions of a class of second order differential equations with piecewise constant mixed arguments and we show that the zero solution of Eq. (1.1) is a global attractor. Also, we study some properties of solutions of Eq. (1.1) such as oscillation, nonoscillation, and periodicity.
Existence, uniqueness and convergence of approximate solutions of nonlocal functional differential equations
Authors:   DEPARTMENT OF MATHEMATICS BIRLA INSTITUTE OF TECHNOLOGY AND SCIENCE PILANI-GOA CAMPUS GOA, INDIA E-mail address: malikiisc@gmail.com, MUSLIM M. , AGARWAL R. P. ,   DEPARTMENT OF MATHEMATICAL SCIENCES FLORIDA INSTITUTE OF TECHNOLOGY 150 WEST UNIVERSITY BOULEVARD MELBOURNE, FL 32901, USA E-mail address: agarwal@fit.edu
Published: May 2021

In this paper, we study a class of nonlocal abstract functional differential equations in a separable Hilbert space H. Using the theory of analytic semigroups we establish the existence, uniqueness and convergence of approximate solutions. We also give some examples to illustrate the applications of the abstract results.
Pseudoparabolic inequalities
Authors:   COLFE’S SCHOOL HORN PARK LANE LONDON, SE12 8AW, UNITED KINGDOM E-mail address: ceciliacraciun@yahoo.com, CRACIUN CECILIA , LUNGU N. ,   TECHNICAL UNIVERSITY OF CLUJ-NAPOCA DEPARTMENT OF MATHEMATICS C. DAICOVICIU 15, 400020 CLUJ-NAPOCA, ROMANIA E-mail address: nlungu@math.utcluj.ro
Published: May 2021

In this paper we apply the Picard operators technique to a pseudoparabolic inequality. We establish existence and uniqueness of the solution to the corresponding Darboux problem, and derive Gronwall-type results for the solution to the pseudoparabolic inequality. We use the Riemann function to represent the solution x ∗ of some particular pseudoparabolic equations.
Positive solutions of functional-differential systems via the vector version of Krasnoselskii’s fixed point theorem in cones
Authors:   BABES–BOLYAI UNIVERSITY DEPARTMENT OF MATHEMATICS 400084 CLUJ-NAPOCA, ROMANIA E-mail address: sorinbudisan@yahoo.com, BUDISAN SORIN , PRECUP RADU ,   BABES–BOLYAI UNIVERSITY DEPARTMENT OF MATHEMATICS 400084 CLUJ-NAPOCA, ROMANIA  E-mail address: r.precup@math.ubbcluj.ro
Published: May 2021

We study the existence of positive solutions of the functional-differential system ... (0 < t < 1), subject to linear boundary conditions. We prove the existence of at least one positive solution by using the vector version of Krasnoselskii’s fixed point theorem in cones.
Admissible topologies on endomorphism rings
Authors:   DEPARTMENT OF MATHEMATICS AND COMPUTER SCIENCE NORTH UNIVERSITY OF BAIA MARE DR. VICTOR BABES 62/A, 430083 BAIA MARE, ROMANIA E-mail address: abrudan.horea@gmail.com, ABRUDAN HOREA F.
Published: May 2021

We study in this paper admissible topologies on the endomorphism rings of Abelian groups. Various examples of admissible (non-admissible) topologies are given.
Obtención de hidrolizados proteicos bajos en fenilalanina a partir de suero dulce de leche y chachafruto (Erythrina edulis Triana)
Authors: Villafuerte Franklin , Pérez Elevina , Mahfoud Antonieta , Valero Yolmar , Pérez Martínez Amaury
Published: May 2021

La fenilcetonuria (PKU) es causada por una actividad deficiente de la enzima fenilalanina hidroxilasa. En los pacientes con esta deficiencia la fenilalanina (Phe) no puede ser convertida en tirosina, aumentando sus niveles en sangre y de otros metabolitos neurotóxicos, provocando un retraso mental irreversible. El tratamiento fundamentalmente se basa en una dieta controlada de Phe. Sin embargo, los alimentos libres o bajos en Phe son escasos. El objetivo de esta investigación es obtener hidrolizados proteicos con bajo contenido de Phe a partir del suero dulce de leche en polvo y harina de E. edulis Triana. El aislado proteico (96,01% proteína cruda) se obtuvo por solubilización y precipitación de las proteínas de la harina, mientras que las proteínas del suero (15,69% proteína cruda) fueron tratadas en su matriz original. Las proteínas del suero y el asilado fueron hidrolizadas enzimáticamente con pepsina y proteasa de Streptomyces griseus. La concentración de Phe se determinó por fluorometría y por HPLC, de lo cual la Phe de las proteínas del suero es liberada una hora antes que las del chachafruto, debido a que las proteínas del suero en parte fueron hidrolizadas en la elaboración del queso. Además, los resultados de la utilización del carbón activados como captor de Phe indican la reducción total del contenido de este aminoácido en los hidrolizados y la reducción de la concentración de otros aminoácidos.
Phenylketonuria (PKU) is caused by a low activity of the enzyme phenylalanine hydroxylase. In patients with this deficiency, phenylalanine (Phe) cannot be converted to tyrosine, increasing blood levels and other neurotoxic metabolites, causing irreversible mental retardation. The treatment is fundamentally based on a controlled diet of Phe. However, free or low-Phe foods are scarce. The objective of this research is to obtain protein hydrolysates with low Phe content from sweet milk powder and E. edulis Triana flour. The protein isolate (96.01% crude protein) was obtained by solubilization and precipitation of the flour proteins, while the whey proteins (15.69% crude protein) were treated in their original matrix. Serum and asylated proteins were enzymatically hydrolyzed with pepsin and Streptomyces griseus protease. The concentration of Phe was determined by fluorometry and by HPLC, from which the Phe of whey proteins is released one hour earlier than those of chachafruto, due to the fact that the whey proteins were partially hydrolyzed in the elaboration of the cheese. In addition, the results of the use of charcoal activated as Phe captor indicate the total reduction of the content of this amino acid in the hydrolysates and the reduction of the concentration of other amino acids.
Primer reporte de Escherichia coli Productora de Toxina Shiga no O157 que codifica el gen de la enterohemolisina en carne cruda en Colombia
Authors: Herrera Arias Fanny , Santos Buelga Jesús , Villamizar Gallardo Raquel
Published: May 2021

Dentro de los patotipos de Escherichia coli, el grupo STEC puede producir en el ser humano desde diarrea hemorrágica hasta insuficiencia renal aguda e incluso la muerte; el ganado bovino es el principal reservorio de este agente patógeno y por ende la ingestión de alimentos derivados de estos animales de abasto son una fuente muy importante de infección para el hombre. El objetivo principal de este estudio fue determinar la prevalencia de STEC en muestras de carne cruda comercializada en Pamplona-Colombia y en cepas obtenidas a partir de las muestras. Se analizaron cien muestras de carne cruda aplicando la técnica de Reacción en Cadena de la Polimerasa para la detección de los siguientes genes en muestras y en cepas STEC: stx1, stx2, eae y hlyA. Adicionalmente, se estableció el patrón de resistencia-susceptibilidad antibiótica de cepas STEC aisladas empleando métodos regulados. En el 39% de las muestras fue posible detectar el gen stx2; en el 38%, de ellas, se detectaron los genes stx1 y stx2. Además, se aislaron cepas STEC en el 13% de las muestras analizadas, 85% de ellas portaban el gen hlyA. No se detectó la presencia del gen eae o del serogrupo O157. Las cepas aisladas demostraron resistencia frente a algunos antibióticos de primera y segunda generación. En conclusión, se detectó la presencia de genes que codifican factores de virulencia en las muestras de carne analizadas que representan un riesgo potencial para la salud de los consumidores. Este es el primer reporte de STEC no O157 que codifica el gen de la enterohemolisina en alimentos en Colombia.
Within the Escherichia coli patotypes, the STEC group can produce in humans from hemorrhagic diarrhea to acute renal failure and even death; cattle are the main reservoir of this pathogen and therefore the ingestion of food derived from these stock animals are a very important source of infection for man. The main objective of this study was to determine the prevalence of STEC in raw meat samples marketed in Pamplona-Colombia and in strains obtained from those samples. One hundred raw meat samples were analyzed using the Polymerase Chain Reaction technique for the detection of the following genes in samples and in STEC strains: stx1, stx2, eae and hlyA. In addition, STEC strains were isolated in 13% of the analyzed samples, 85% of them carried the hlyA gene. The presence of the eae gene or serogroup O157 was not detected. The isolated strains demonstrated resistance against some first and second generation antibiotics. In conclusion, the presence of genes encoding virulence factors in the meat samples analyzed, that represent a potential health risk factor to consumers, was confirmed. This is the first report of STEC non-O157 that encodes the enterohemolysin gene in foods in Colombia.
Determination of changes during storage in chemical and microbial compositions of yoghurts made from buffalo milk and buffalo and cow milk mixtures
Authors: Çeti̇nkaya Asya
Published: May 2021

This study was aimed to determine and compare the chemical and microbiological properties of yoghurts made from different types of milk and their mixtures (35%, 65%, and 100%) during their storage at 4 °C for 28 days. For this purpose, chemical and microbiological properties of yoghurts during storage at 4 °C for 28 days were investigated. The total amount of dry matter, fat, pH and protein of yoghurt made from the buffalo and cow milk mixtures was significantly higher than that of pure buffalo milk (P<0.01). Also, storage time has led to significant differences in these components. Considering the results of microbiological analysis, a significant (P<0.01) difference was found between yoghurt samples in terms of total count of mesophilic aerobic bacteria, lactobacilli, lactococcus and yeast and mould. Hence, it is concluded that the addition of buffalo milk to that of cow improves the composition of yoghurt made from cow milk, which indicated the possibilities of processing and marketing of both types of milk especially because the health benefits of cow milk and the fermented products are well documented.