bluuebunny/crossref_metadata_2025 huggingface dataset:
Structural performance of connectors in a hardwood stairway handrail guard system
Authors: Quin Jr. Franklin , Franca Tamara , Street Jason , Lim Hyungsuk , Shmulsky Rubin
Published: January 2024

Wood is a preferred material for constructing staircases due to its appealing aesthetic features. The use of wood, especially hardwoods such as red oak (Quercus rubra), white oak (Quercus alba), yellow poplar (Liriodendron tulipifera), and hard maple (Acer saccharum), has been the main construction material for staircases over the years. Staircase designs have evolved because of the flexibility of wood and working with specialized manufacturing machinery. A stair guard system connection must be designed to resist rotational and translational movements whenever a force is applied to the handrail. The demand for structural design values in wooden stair guards has been steadily increasing, driven by the needs of engineers, designers, builders, and end-users alike. This paper presents experimental data for four stair guard connections (post-to-rail, infill-to-footing, infill-to-rail, and rail-to-rail) encountered in a hardwood stairway handrail guard system. The data generated from this research could be useful for modeling the structural behavior of the connections.
Comparative analysis of photo-fermentation hydrogen production from pretreated corn stover by deep eutectic solvents
Authors: Li Cunjie , Lu Yanwei , Liu Yanyang , Yue Jianzhi , Zhou Xiaokai , Jing Yanyan
Published: January 2024

To compare the pretreatment effect of deep eutectic solvents (DESs) on corn stover, three types of DESs (acid, neutral, and alkaline) were used to pretreat corn stover, and their effects on lignin removal were investigated. Then the performance of photo-fermentation hydrogen production (PFHP) using DESs pretreated corn stover was compared and analyzed. The results showed that acid DESs had the best lignin removal efficiency, and the lignin removal percentages of choline chloride/formic acid (ChCl/Fac) and choline chloride/oxalate (ChCl/Oac) were 64.7% and 65.6%, respectively. The alkaline DESs had the second highest removal of lignin, while the neutral DESs had a poor effect on lignin removal. The comparison of hydrogen production indicated that the corn stover pretreated with ChCl/Oac had the best hydrogen production effect. In conclusion, the DESs pretreatment can obviously remove the lignin in corn stover, and then improve the hydrogen production capacity and efficiency of photo-fermentation, which provides a potential pretreatment method for the efficient utilization of straw biomass.
Potential use of nanofibrillated cellulose-loaded cationic starch solutions as coating formulation for recycled fluting papers
Authors: Tozluoğlu Ayhan
Published: January 2024

Effects of cellulose nanofibers (CNF) and cationic starch (CS) were evaluated as coating components relative to the physical and mechanical properties of fluting papersheets fabricated from recycled corrugated cardboard fibers. Fabricated fluting papers were subjected to size press applications by three different coating blends. Coating suspensions were prepared at various concentrations of CNF (0.5%, 1%, 2%, 3%, and 4%) and 4 wt% CS, and the same amounts of CS/CNF. The paper sheets were fabricated using size press machine as three-time repetitive applications, followed by one-time drying section, and compared to uncoated, CS-coated, and CNF-coated papers. The application of CNF suspensions increased tensile indices up to 11.7%. Moreover, CS/CNF suspensions resulted in a 67.2% increase in tensile index values. The coating of CS/CNF suspensions increased the burst index values by 163% at the CS+1%CNF concentration when compared to the control pulp. Surface application of prepared suspensions reduced the porosity of the samples under all conditions. The highest reduction in the air permeability was observed in the CS+4%CNF-coated samples as 91.5%. It can be concluded that the superficial applications of CNF on the physical and mechanical properties of recycled fluting paper was more effective in the presence of CS.
Liberalismo, ciudadanía y sectores populares: la venta callejera limeña como estrategia para el ejercicio de la ciudadanía a mediados del siglo XIX
Authors: Hidalgo Mantilla Juan Carlos
Published: January 2024

En Lima, a mediados del siglo XIX, la ciudadanía fue condicionada y restringida para una minoría selecta que justificaba sus privilegios con derechos. En ese contexto de desigualdad, los sectores populares limeños, carentes de patrimonio y grandes ingresos, asimilaron el liberalismo y lo adecuaron a sus condiciones de vida para ejercer su condición de ciudadanía. El objetivo es demostrar cómo los sectores populares limeños, por medio de un oficio o trabajo, ejercen su ciudadanía. Para ello, se analizará testimonios de intelectuales y viajeros de época, artículos periodísticos y documentos del Archivo Histórico de la Municipalidad de Lima, que expliquen el modo en que la venta callejera generó honra y reconocimiento social para el ejercicio ciudadano.
Un libro para la revolución. Por la emancipación de América Latina y el Plan Político del joven Haya de la Torre, 1923–1927
Authors: Ruiz Zevallos Augusto
Published: January 2024

El artículo aborda el primer libro de Haya de la Torre, Por la emancipación de América Latina. Su publicación en mayo de 1927 estaba enlazada al proyecto de una insurrección armada en el Perú que iniciaría la revolución continental. Era una guía doctrinal para encaminar la revolución, con una lectura del pasado y del presente y una propuesta de futuro (un camino autóctono y autónomo hacia el socialismo). Era además un medio discursivo orientado a constituir una realidad inmediata: un “partido/ frente único”, con militantes disciplinados y dispuestos a la acción armada, una periferia de simpatizantes e intelectuales para gobernar y un liderazgo mesiánico científico, el de Haya de la Torre. En la medida que ese discurso ganaba concreción, colisionaba con los planteamientos de José Carlos Mariátegui -líder con gran predicamento-, y con ello el libro, pese a resultar útil para la gestación y fundamentación del movimiento aprista, perdió sentido.
Drinot, Paulo. (2023) José Carlos Mariátegui o el «cojito genial». Historia y discapacidad en el Perú
Authors: Luyo Soto Diego Alonso
Published: January 2024

¿Sabéis quién es Mariátegui? Es la pregunta de Henri Barbusse que nos interpela y cuestiona desde la tumba del Amauta. El historiador Paulo Drinot la retoma y, partiendo de los campos de la historia de la salud, ya visitados en sus trabajos anteriores, ofrece nuevas luces sobre José Carlos Mariátegui, el padre del socialismo peruano, desde una mirada necesaria: su discapacidad física. Su figura ha sido tan poderosa que le ha valido la creación de un ismo, la inclusión de su apellido en el nombre de un partido político en la década de los 80s y decenas, sino cientos de representaciones artísticas, tanto gráficas como plásticas.
El principio de legalidad penal y la necesidad de una redacción adecuada del delito de minería ilegal
Authors: Ruiz Bravo Hernan
Published: January 2024

La redacción del delito de minería ilegal presenta algunas falencias que hasta la fecha no han sido corregidas. La última modificación del Decreto Legislativo N° 1102 por el D.L N° 1351 establece que el elemento normativo “realizar un acto minero” se realice sobre un recurso metálico y no metálico, lo cual solo puede ser cumplido en la región Madre de Dios y no en todo el territorio nacional. Esto resulta contraproducente, considerando que la minería ilegal está presente en 21 de las 25 regiones del país. La mala redacción hace que, por principio de legalidad penal, el acto de beneficio no sea sancionado como delito de minería ilegal. La redacción de este delito puede ser mejorado para evitar impunidad de dos maneras: incorporando cada uno de los actos mineros de la LGM en el artículo 307-A o cambiando la forma de redacción de este «el que realice un acto minero (...)».
De la revocación de licencias de edificación en el derecho peruano
Authors: Villanueva Haro Benito Roberto
Published: January 2024

El presente trabajo de investigación analiza y evidencia que toda Licencia de edificación, como acto administrativo que la contiene, es mutable y responde al interés público de una realidad normativa cambiante, que podría responder a exigencias técnico normativas en un momento determinado. En ese sentido, surge el interés de incursionar en el instrumento de la revocación como figura jurídica por la cual puede dejarse sin efecto en cualquier momento el acto administrativo que contiene la licencia de edificación.
Informality and Competition
Authors: Tello Mario D.
Published: January 2024

Based upon the changes of labor productivity for the economy decomposed by sectors and activities, this paper proposes three hypotheses on the relationship between the informal sector and competition for Peruvian economy in the period 2007-2018. The first one postulates that there might exist product market segmentation between formal and informal firms. The second postulates that the effects of the PTAs on the changes of labor productivity in activities and sectors have been diverse and unclear. The last and third hypothesis postulates that labor productivity changes in Peru and its within and reallocation components have been associated with the fluctuations and the rate of growth of the GDP and the terms of trade. These associations are consistent with the primary- export structure of the Peruvian economy.
Unobserved effects of monetary policy in the Peru’s departments output and unemployment
Authors: Mendoza Vargas Oscar Manuel
Published: January 2024

This is the first article in a series of two. A NAIRU-Keynesian model is developed for Peru’s departments (regions) to analyse whether there is a stable relationship between inflation and unemployment, and inflation and the output gap as documented in the Peruvian literature. I applied GLS for model estimation. My results document a positive relationship between future inflation rates and the gap in departmental unemployment rates concerning national unemployment rates, I evidence the Phillips curve flattening at the departmental level when estimating with the output gap, which is consistent with the national aggregate models, but there is a more elastic relationship when estimating with departmental unemployment rates. This represents unobserved effects for the monetary policy maker and requires further research.
Gerstle, G. 2022. The Rise and Fall of the Neoliberal Order: America and the World in the Free Market Era
Authors: Chire Apari Juan Jesus
Published: January 2024

El neoliberalismo es una teoría política y económica que se encuentra a favor de reducir la intervención del estado en la economía. Reconoce el valor individual y aboga por el cosmopolitismo social. Además, apoya la globalización como un generador de beneficios mediante el comercio internacional. Esta teoría inició su auge en la década de 1970, tras la imposibilidad del keynesianismo para hallar una solución al problema de ralentización económica que enfrento el mundo.
Usman, Z. 2022. Economic Diversification in Nigeria: The Politics of Building a Post-Oil Economy
Authors: Cortez Flores Jose Luis
Published: January 2024

Nigeria se caracteriza por episodios de crecimiento irregular, es dependiente de los ingresos de las exportaciones de petróleo, tiene graves disparidades regionales y el factor político es importante en las decisiones estatales que han originado y profundizado el reto de diversificación económica. Esta problemática ha llevado a diversos investigadores a realizar diversas críticas y recomendaciones relativas a la situación descrita.
Limited Efficiency of Monetary Policy on Local Inflation Rates and Output
Authors: Mendoza Vargas Oscar Manuel
Published: January 2024

This is the second article of a series of two that documents the limited efficiency of the Peruvian monetary policy on local inflation rates. With this research I deepen on my preliminary findings on the unobserved effects of Peruvian monetary policy using departmental Phillips curves. On this occasion, the motivation seeks to answer the question: by incorporating the NAIRU-Keynesian and neo-Keynesian structural model criteria for the Peruvian case, what other unobserved effects of monetary policy would be found in Peru’s departments?
Two models of structural equations are developed to estimate the impact of monetary policy at sub-national levels, the first considers the unemployment rate (NAIRU-Keynesian) and the second considers the departmental GDP gap, from which there are counterproductive results that start from the misalignment of departmental economic cycles with the national one which generates inefficiency of monetary policy to reduce departmental inflation, the increase in departmental unemployment and the decrease in the departmental GDP gap.
Análisis y diseño de un PORTAL web para asistir al cuidado de pacientes con accidente cardiovascular
Authors: Cortez-Vásquez Augusto , Pro-Concepción Luzmila , Mamani-Macedo Néstor
Published: January 2024

When blood flow to a part of the brain stops for a few seconds, a cerebrovascular accident (CVA) also known as a stroke (MedlinePlus, 2022) occurs, causing it to be unable to receive nutrients and oxygen, causing permanent damage or even death. The WHO points out that strokes are one of the main causes of death in men and women, this was accentuated during the COVID 19 pandemic. Technology can help the people involved, be they patients, family members, caregivers and medical personnel to mitigate the derived effects. The main objective of the study is to design a web portal that helps people by offering them, in an easy and integrated way, access to a series of resources and services, which can be of great help (NetCommerce, 2022), for this, three Fundamental aspects: Information, Participation and Comfort, giving them access to the greatest amount of information from the same site, always considering that the resources offered by the web must be accompanied by a good education for their proper use.
Asimilación, vulnerabilidad y subordinación cultural en torno a la realidad Mapuche en Chile
Authors: Del Valle-Rojas Carlos , Loayza-Javier Jerjes
Published: January 2024

En un contexto de despojo contra el pueblo Mapuche, se aplican 7 entrevistas a profundidad desarrolladas durante los años 2020 y 2021 a mujeres y hombres provenientes de la etnia mapuche que, actualmente, vienen desempeñándose en labores académicas, organizacionales y políticas. El artículo busca debatir la asimilación social, cultural y económica de la población mapuche en su proceso de “chilenización”. En este proceso se identifica la vulneración contra la identidad mapuche, la segregación racial y de clase hacia quienes deciden migrar y movilizarse socialmente, así como la lógica de una subordinación cultural que mella constantemente la libertad mapuche, de su lengua, de sus costumbres, de su cosmovisión y, en general, de su derecho a disentir.
The problems and perspectives of the training of applied mathematicians
Authors: Ivanauskas Feliksas , Pekarskas Vidmantas
Published: January 2024

The article gives a survey of the problems and perspectives of the training of applied mathema­ticians. The syllabus of applied mathematics is discussed too.
Polynomials with many roots on a circle
Authors: Dubickas Artūras
Published: January 2024

There is not abstract.
On weak solutions of Stratonovich integral equation driven by a continuous p-semimartingales
Authors: Kubilius Kęstutis
Published: January 2024

There is not abstract.
Convergence of numerical solution of stochastic differential equation for the self-thinning process
Authors: Rupšys Petras
Published: January 2024

For theoretical and practical analysis of the self-thinning process we use stochastic differential equation, which take the form:
dN (t) = N (t) (α - β ln N (t))dt + μN (t)dW (t), N(t0) = N0, t0 ≤ t ≤ T,
where N – tree per hectare (stem/ha), t – stand age, W(t) – scalar standard Brownian motion, N0 – not random, α, β and μ are parameters – real constants. In this paper from a practical viewpoint we apply a simple numerical method for solution of the stochastic differential equations by the Milstein's higher order method. The programs for numerical simulation are written on MAPLE. The convergence of this model is explored too.
Realization of operator expressions for the solutions of differential equations
Authors: Bikulčienė Liepa
Published: January 2024

There is not abstract.
On representation formula for solutions of Hamilton–Jacobi equations for unbounded initial conditions
Authors: Gudynas Gintautas
Published: January 2024

There is not abstract.
Internet application Mozilla localization and using in teaching
Authors: Grigas Gintautas , Jevsikova Tatjana
Published: January 2024

The analysis of Intemet application Mozilla using at school is presented. The reasons to discuss this topic are following: 1) the programs' suite was localized (menu, dialog boxes and other strings and documentation are translated and the program is adapted for its proper matching to Lithuanian environment); 2) using one Mozilla package for teaching Intemet topics instead of separated Inter­net applications (web browser, HTML composer, e-mail and chat clients) has many advantages.The new features, added into Mozilla during its localization, are described, farther improvement possibilities are evaluated and a short curriculum is presented.
Informational architectures of asynchronous and synchronous learning models
Authors: Jarmuškaitė Lina , Kulvietienė Regina , Šileikienė Irma
Published: January 2024

There is not abstract.
Research of the object-oriented programming learning environment
Authors: Lipeikienė Joana , Kalpaitė Kristina , Kluonytė Aušra
Published: January 2024

Research and results of the use of C++ Learning Environment for teaching at Vilnius Pedago­gical University are described in this paper. Results of questionnaires and Web Ct statistical data were used for the research.
A mathematical model of a nuclear reactor with delay depending on the power of the reactor
Authors: Bučys Kostas , Grigolienė Rasa , Janutėnienė Jolanta , Švitra Donatas
Published: January 2024

There is analysed the problem of the stability of the reactor using a nonlinear mathematical model. By the method of D-decomposition there is done linear analysis and obtained a region of asymptotic stability D0 and the region D2 in which there appear a stable periodical solution. The nonlinear analysis of the model was done with the help of the theory of bifurcations. There is received an approximate periodical solution of one frequency of the model and determined the `degree of harmonicity'' of the solution.
Statistical modelling of ozone concentration in troposphere
Authors: Girgždienė Rasa , Rekašius Tomas
Published: January 2024

Statistical analysis of the ozone concentration data received from the background monitoring stations located in Lithuania is performed. The goal of the study is modelling of ozone background concentration trend-cycle component. The regression models obtained include ozone concentra­tions at foregoing moments, local meteorological factors (such as air temperature, solar activity, wind speed and its direction, ect.), their lags and interactions.
Numerical simulation of the current-voltage characteristics of the inhomogeneous Schottky diodes
Authors: Pincevičius Albertas , Rakauskas Rimantas-Jonas
Published: January 2024

In this paper we offer methods for estimation parameters of diodes of the Schottky by compa­ring outcomes of calculations and experiment. Definite some parameters of contact area: allocation of a active impurity in this area, to define more precisely a potential barrier in the area, to study tunnel mechanisms of electrons through this potential barrier. Such tasks are important from the practical point of view at improvement of performances of devices. One more problem the proce­dure helps to decide-to design devices with the established volt-ampere characteristic. In this case we can offer the corresponding allocation of an impurity in contact area, to select a technology for engineering of contact of the Schottky.
Parallel algorithms for solving of multidimentional vibrational Shrodinger equation
Authors: Rakauskas Rimantas-Jonas , Šulskus Juozas , Vošterienė Svajonė
Published: January 2024

There is not abstract.
Mathematics in economics and business studies
Authors: Apynis Antanas , Stankus Eugenijus
Published: January 2024

The books in microeconomics and macroeconomics are considered in view of mathematics consepts. The syllabus of mathematics for economics and business students is presented.
Teaching of decimal positional number system and decimal fractions in the 5-th grade
Authors: Bakštys Albertas , Šukienė Irena , Viliminė Albina
Published: January 2024

Long, almost 3500 years delay was observed, until the notion of positional number system originating from Babylon was introduced in Western Europe and, afterwards, in aIl over the modern world. This proves that acquaintance with such a complex concept as decimal fraction is must be started long before the arithmetic of decimal fractions is introduced. Teachers working experience using A. Bakštys and G. Bakštys textbook [5] in the 5-th grade is described in this paper.
Experiment as methods of student's methods of mathematical research activity
Authors: Balčiūnas Sigitas , Freibergaitė Daiva
Published: January 2024

The article deals with the mathematical experiment method on the basis of the constructivist theory. The types of experiment are illustrated by mathematical samples at school. The samples of mathematical experiments out by students are displayed.
Saliamonas Antanaitis (1894–1973) and his research into the old mathematics
Authors: Banionis Juozas
Published: January 2024

Antanaitis is one of the 20th century Lithuanian professional mathematicians, who trained pedagogues at Teachers' Colleges in the 3–4th decades. After World War II S. Antanaitis worked in the Gymnasium of the 16th of February in Western Germany. He won distinction in research into mathematics. S. Antanaitis published articles on mathematics. There was a critique, some articles touching upon questions of methodology and mathematics history. Articles on mathematics history must be paid attention to because they threw the light both on the portraits of the famous creators in the period of elementary mathematics (until 17th century) and their merits in this scientific field. One of those articles was up for a famous astronomer and mathematician Johan Kepler (1571–1630). Another one was an original book about a scientist of Ancient Greece Archimedes (287 BC–212 BC). S. Antanaitis having made a thorough analysis of works of European science historians presented these science personalities and underlined importance of their works for the development of the higher mathematics.
The influence of the secondary school-learning examination in mathematics on the studies at the university
Authors: Čirba Stasys , Daunoravičius Jonas
Published: January 2024

The dependency of good results of the first year students of the first stage upon the final exami­nation of mathematics taken at school, upon the evaluation mark obtained as well as upon the school location whether secondary school was finished in town or in some country district is discussed.Admitting students to VGTU when counting scores of competition exams 10 scores are added to those who took the state examination in mathematics.The analysis of the studies of the first session having done it was obtained that 13 scores should be added additionally.
The validation of mathematical skills application tasks
Authors: Kiseliova Danutė , Kiseliovas Arkadijus , Donielienė Ingrida , Kiseliova Orinta
Published: January 2024

There is not abstract.
Thirty years to the seminar of the number theory
Authors: Laurinčikas Antanas
Published: January 2024

In the paper a survey of the activity of the seminar of the number theory is given.
Possible restrictions of mathematics learning in transition from a teaching model to a learning model
Authors: Novikienė Regina , Petraitienė Stasė
Published: January 2024

The problem on changes of higher education pedagogics, however, is particularly urgent, since traditional pedagogics, when teaching is considered as a communication process meets demands of society no longer. A traditional education form, i.e., a lecture, does not develop abilities, possession of which would lead to the formation of a studying society. Thus a problem occurs, which may be defined by the following questions: ln which way a didactic process shall be organised in order to ensure the development of necessary abilities? What are the restrictions, characteristic to the transition to the process mentioned?The article consists of two parts. First part discusses the way for theoretical grounding of a change possibility for a mathematics learning model. Second part reveals theoretic restrictions, which may occur, while changing a model of studying.
On teaching mathematical modelling
Authors: Valakevičius Eimutis
Published: January 2024

The purposes of this paper is to suggest aims and learning outcomes in teaching mathematical modelling and how to present material of the subject.
General definition of mean
Authors: Vilkas Robertas
Published: January 2024

In this article there is presented general definition for mean. Also many interesting examples are given.
Decision procedure for a fragment of quantified branching temporal logic
Authors: Pliuškevičienė Aida
Published: January 2024

There is not abstract.
Comparison of likelihood ratio rule with plug-in rule in classification
Authors: Dučinskas Kęstutis
Published: January 2024

There is not abstract.
The cointegration analysis of the Lithuania's macroeconomic indicators
Authors: Firkovič Viktorija
Published: January 2024

Most of the existing technigues of the macroeconomic indicators analysis can not be succefully applied to the common situation of a limited data set. The goal of the work is to estimate the evolution of Lithuania's macroeconomic indicators using the vector cointegrated anlysis combined with the recursive metod proposed by R. Rudzkis and G. Vilutis (2001).
The influence of temperature to the arrival dates of spring migrants
Authors: Ivanauskas Feliksas , Lapinskas Remigijus , Nedzinskas Vytautas
Published: January 2024

We establish that the day when the average temperature of the 20 days before that for the first time in the year reaches +3 degrees centigrade is the best predictor of the arrival date of the tufted duck to the Zuvintas reservation, Lithuania.
The survival regression model of competing risks for the family of Farlie–Gumbel–Morgenstern distributions
Authors: Jakaitienė Audronė , Zuokas Danas
Published: January 2024

In this paper the trivariate survival regression model for FGM family of distributions is const­ructed with marginal left-truncated logistic distributions. Two methods (using survival and hazard functions in the first case, and distributional density and ` `conditional'' survival function in the se­cond case) are used when constructing likelihood function for model parameter estimation. Const­ructed survival model was run with the data of the  ` `KRIS'' (The Kaunas Rotterdam Intervention Study), which lasted for 22 years from 1972. The results show, that using second case for likehhood function construction gives better approximation for the data, because some additional conditions are considered.
Procedure of the removal of the outliers from the sample satisfying the multidimensional Gaussian mixture model
Authors: Jakimauskas Gintautas
Published: January 2024

There is not abstract.
Comparison of various clustering algorithms efficiency
Authors: Ruzgas Tomas
Published: January 2024

This article illustrates the problem of clustering efficiency of Gaussian mixture models using various clustering methods. The results of investigation by simulation are discussed.
One class of Nash equilibria in bimatrix games
Authors: Blaževič Aneta Gracjana , Sūdžiūtė Daina
Published: January 2024

Active Nash equilibria existence in bimatrix game problem is reduced to the problem of nonexistence of special solutions of the systems (11) and (12).
Comparison of the stability of discontinuous Galerkin and finite-difference methods
Authors: Čiegis Raimondas , Čiegis Remigijus , Suboč Olga
Published: January 2024

In this article we present stability analysis of two discrete schemes, which are used to solve a parabolic problem on adaptive nonstationary meshes. The influence of interpolation and projection errors is investigated. It is proved that interpolation error accumulates during computations while projection error has much better stability properties. Numerical examples illustrate these theoretical results.
Interpolation of periodical functions by splines
Authors: Plukienė Danutė , Plukas Kostas
Published: January 2024

Interpolating periodical splines estimation methods are considered in this paper. Periodical spli­ne universal implementation method is presented.
Automatic aggregate modelling
Authors: Žvironienė Aušra
Published: January 2024

There is not abstract.
Analysis of a immunity system using qualitative methods
Authors: Kavaliauskas Algis
Published: January 2024

The article deals with analysis of reciprocity model of cancer cells and lymphocites, when cancer cells are restricted by cylindrical surfaces. The growth of cells is possible in the direction of radius and altitude in different speeds. The qualitative analysis of stationary values of this model is done.
The approximation problems of solutions of the compressible fluid flow in an exterior domain
Authors: Leonavičienė Teresė
Published: January 2024

The approximation of solutions of the three-dimensional steady compressible flow (linearized problem) in an exterior domain is studied. The formal error estimates are obtained.
Convergence of products of independent random variables to the log-Poisson law
Authors: Lileikytė Reda , Šiaulys Jonas
Published: January 2024

There is not abstract.
Large deviation theorems for weighted summation of Gamma-distribution random variables
Authors: Saulis Leonas
Published: January 2024

There is not abstract.
Optimal allocation of means for trauma prevention using stochastic programming
Authors: Vakrinienė Sigutė , Čyras Petras
Published: January 2024

Optimal criterion for allocation of means necessary for trauma prevention is proposed. The problem is simulated as a matrix game with random elements.
Data mining technologies based on IBM intelligent miner
Authors: Kulvietienė Regina , Mamčenko Jelena
Published: January 2024

There is not abstract.
High energy laser & systems to neutralise stellar coronal mass ejections (CME) plasma
Authors: Lutz Kolemann , Trevino Terry
Published: January 2024

With CME plasma and shockwave travelling at 600+ km/sec, active methods such as high energy electron lasers (HEL) and mirrors are effective at making contact with ionised atoms in CME. Electrons pulsed from kW to MW laser(s) could polarise ionised atoms such as Fe16+, O7/8+, Mg, He2+,etc to fill valence pairs. As high-FIP atoms are electromagnetically trapped with a higher susceptibility from lower e- density and temperatures, CME plasma clouds can be neutralised, separated, and reduced in velocity trajectory around planet. Study outlines interactions between Electron Laser and CME plasma cloud, orbital geometry, build of high energy lasers, subsystems, as well as recoils, and cloud charge dynamics with e- interactions to neutralise CME particles. Additional space-based systems are designed such as mirrors in closer orbit to align lower velocity light beams. In approaching higher electron recombination and FIP ionisation of laser-plasma ion cluster density, max absorption of e- to CME could be approached with similar beam, CME, mirror angles and alignment, where e- couple and fill valence shells. Models evaluate efficacy of coherent laser beams of charged electrons, X-rays, infrared (IR), and/or electron/radio Hz to polarize CME column charge densities, with optimal CME scatter geometry and time window. Low cost ground experiments are discussed. Models suggest every ~1 km gap laser creates when CME t=8.255min creates a 10,067 km gap for Earth to orbit through. Such a HEL laser, reflecting mirrors, and space systems could neutralize plasma CME Cloud within 92.818M mi (Sun-Earth distance) and mitigate effects and trillion dollar costs from Carrington-type CME flares, and supernovae.
Potensi Ekstrak Kulit Buah Pepaya (Carica papaya L.) Untuk Isolasi Kolagen Cumi-cumi (Loligo sp.) Sebagai Penyembuhan Luka Kulit Mencit (Mus musculus)
Authors: Astria Angelia , Prasetyaningsih Aniek , Prakasita Vinsa Cantya
Published: January 2024

AbstrakKulit buah pepaya merupakan bagian dari buah pepaya yang tidak dikonsumsi dan mengandung enzim papain yang dapat digunakan sebagai pengganti papain murni untuk mengekstraksi kolagen. Tentakel cumi-cumi merupakan salah satu dari bahan baku marine collagen. Ekstraksi kolagen dari tentakel cumi-cumi menggunakan metode maserasi menggunakan CH3COOH dan penambahan ekstrak kulit buah pepaya pada konsentrasi 5, 10, 15, dan 20%. Hasil menunjukkan bahwa konsentrasi 15% ekstrak kulit buah pepaya memberikan rendemen yang terbaik yaitu 19,2% (w). Kolagen yang dihasilkan memenuhi kriteria Badan Standardisasi Nasional (BSN) (2014) pada jumlah mikrobia dan total coliform tetapi belum memenuhi pada kadar protein, pH, dan kadar air. Pada uji preklinis digunakan kolagen hasil ekstraksi dengan penambahan 20% ekstrak kulit buah pepaya yang memenuhi kriteria BSN dengan kadar protein terbanyak. Serum kolagen dibuat menjadi tiga konsentrasi, yaitu 5, 10, dan 20 mg/mL. Hasil pengujian preklinis menunjukkan bahwa kelompok perlakuan kolagen 20 mg/mL memiliki presentase penutupan luka kulit mencit terbaik sebesar 84,61%, dari hasil pengujian statistik menunjukkan tidak ada perbedaan signifikan dengan kelompok perlakuan kontrol positif.AbstractThe papaya peel, which is a part of papaya not typically consumed, contains the papain enzyme that can be used as a substitute for pure papain to extract the collagen. Squid tentacles are one of the mainsources of marine collagen. The extraction of collagen from squid tentacles was conducted using a maceration method with CH3CHOOH solvent, and the papaya peel extract was added at concentrations of 5, 10, 15, and 20%, respectively. The extraction process showed that the addition of 15% papaya peel extract provided the best result of 19.2% (bb). The collagen produced in this experiment met the BSN criteria for total microbes and total coliforms. However, it did not yet comply with the BSN criteria for protein content, pH, and water levels. The preclinical testing utilized the extracted collagen and the papaya peel extract with a 20% concentration, which met the BSN standards with the highest protein level. The serum collagen was divided into three concentrations: 5 mg/ml, 10 mg/ml, and 20 mg/ml. Preclinical studies showed that the treatment group receiving 20 mg/mL collagen exhibited the highest percentage of skin wound healing at 84.61%, and the statistical test found no significant difference compared to the positive control treatment group.
Short Communication: Morphophysiological Response to Partial Submergence and Water Deficit in North Sulawesi Local Rice
Authors: Nio Song Ai , Kakanga Christine J.R. , Koda Marlince , Ludong Daniel Peter Mantilen
Published: January 2024

Flood and drought are two disasters that resulted in crop failure, including rice production. The objective of this study was to evaluate the morphophysiological characteristics of North Sulawesi local rice (Oryza sativa L.) cultivars as response to partial submergence and water deficit at the vegetative phase based on plant height, number of leaves, root length and volume, and leaf total chlorophyll concentration. The factorial experiment in Completely Randomized Design consisted of four rice cultivars (Superwin, Ombong, Temo, and Burungan) and three treatments (well-watered, partial submerged, and water deficit). The treatments commenced at four-fully-expanded leaf stage for 14 days. Plant height and leaf number were recorded on day 0 (before the treatments commenced), 7, and 14 after treatments. The length and volume of roots as well as total chlorophyll were recorded at 14 days after treatment. Root length was potential indicator of partial submergence and water deficit as it was higher under partial submergence and water deficit than well-watered. Root volume was potential indicator of partial submergence as it was larger under partial submergence than water deficit and well-watered. The partial submergence and water deficit tolerance of North Sulawesi local rice should be further evaluated based on the other characteristics.AbstrakKebanjiran dan kekeringan merupakan bencana alam yang mengakibatkan kegagalan panen, termasuk produksi beras. Penelitian ini bertujuan untuk mengkaji karakterisitik morfofisiologis pada padi (Oryza sativa L.) lokal Sulawesi Utara sebagai respons terhadap kebanjiran dan kekeringan pada fase vegetatif berdasarkan tinggi tanaman, jumlah daun, panjang, dan volume akar serta kandungan klorofil daun. Percobaan faktorial dalam Rancangan Acak Lengkap ini menggunakan empat kultivar padi (Superwin, Ombong, Temo, dan Burungan) serta tiga perlakuan (diairi, digenangi, dan tidak diairi). Perlakuan dimulai pada saat tanaman mempunyai empat daun yang berkembang penuh selama 14 hari. Tinggi tanaman dan jumlah daun diamati pada hari ke-0 (sebelum perlakuan dimulai), hari ke-7, dan 14 setelah perlakuan. Panjang dan volume akar serta kandungan klorofil daun diukur pada 14 hari setelah perlakuan. Panjang akar merupakan indikator yang potensial untuk kebanjiran dan kekeringan karena panjang akar saat kebanjiran dan kekeringan lebih besar daripada diairi. Volume akar merupakan indikator yang potensial untuk kebanjiran karena volume akar saat kebanjiran lebih besar daripada saat kekeringan dan diairi. Toleransi padi lokal Sulawesi Utara terhadap kebanjiran dan kekeringan perlu dievaluasi lebih lanjut berdasarkan karakteristik lainnya.
Pengelolaan dan Pengayaan Koleksi Biji Begonia di Bank Biji Kebun Raya Cibodas Jawa Barat
Authors: Lailaty Intani Quarta , Mufida Yulita Ratna , Kurniawan Vandra , Efendi Muhammad
Published: January 2024

AbstrakBank biji merupakan salah satu solusi yang baik dalam pemeliharaan plasma nutfah secara ex-situ, karena dianggap lebih efektif dan efisien dalam penyimpanan. Bank biji di Kebun Raya Cibodas (KRC) telah mengoleksi 147 jenis biji dari 102 marga dan 61 suku. Penyimpanan biji ukuran kecil masih menjadi suatu tantangan dan peluang tersendiri untuk diteliti dan dikembangkan. Dalam tulisan ini akan dibahas mengenai pengelolaan dan pengayaan koleksi biji ukuran kecil, seperti Begonia, di bank biji KRC. Prosedur pengelolaan biji di bank biji KRC meliputi pemanenan, pemrosesan, pengujian, dan penyimpanan biji. Tiap jenis biji akan diberi nomor koleksi sesuai prosedur di bank biji. Pengujian viabilitas biji menggunakan metode cut test dan uji Triphenyl Tetrazolium Chloride (TTC). Biji-biji yang dikoleksi di bank biji KRC berasal dari tumbuhan koleksi kebun dan hasil eksplorasi biji secara khusus di wilayah Jawa dan Sumatra. Terdapat 12 penambahan jenis biji Begonia di bank biji KRC, antara lain Begonia multangula, B. muricata, B. isoptera, B. areolata, B. stictopoda, B. repanda, B. chiasmogyna, dan B. atricha yang berasal dari Gunung Tilu, Jawa Barat dan Gunung Slamet, Jawa Tengah. Uji viabilitas menggunakan TTC menunjukkan warna merah dengan perlakuan perendaman 24 jam dan pre-treatment pada B. repanda. B. longifolia memiliki karakter simpan serupa biji ortodoks berdasarkan studi literatur dan 100 seed test termodifikasi.AbstractSeed bank is a good solution for ex-situ germplasm maintenance. It is considered more effective and efficient in storage. The seed bank at Cibodas Botanic Gardens (CBG) has collected 128 types of seeds from 102 genera and 61 families. Storage of microscopic seeds still be a challenge and opportunity to be observered and developed. In this paper, we will discuss the management and enrichment of microscopic seed collections, such as Begonia, at the CBG’s seed bank. Seed management procedures at the CBG’s seed bank include harvesting, processing, testing and storage of seeds. Each type of seed will be assigned a collection number according to the procedure at the seed bank. The seed viability test used the cut test method and the Triphenyl Tetrazolium Chloride (TTC) test. The seeds collected from collection plants of CBG and seed exploration specifically in Java and Sumatra. There are 12 additional species of Begonia seeds in the CBG’s seed bank, including Begonia multangula, B. muricata, B. isoptera, B. areolata, B. stictopoda, B. repanda, B. chiasmogyna, and B. atricha from Mount Tilu, West Java and Mount Slamet, Central Java. Viability test using TTC showed a red color with 24 hours immersion treatment and pre-treatment on B. repanda. B. longifolia has storage characteristics similar to orthodox seeds based on literature studies and 100 modified seed tests.
Efek Pemberian Ekstrak Kulit Pisang Kepok (Musa acuminata x balbisiana) Terhadap Kulit Mencit (Mus musculus) yang Terpapar Sinar Ultraviolet
Authors: Maretta Gres , Fitriya Ika , Putra Ramadhani Eka , Ramadhani Untia Kartika Sari
Published: January 2024

AbstrakPendedahan kulit secara langsung oleh sinar ultraviolet dalam jangka panjang dapat menimbulkan kerusakan pada kulit. Kerusakan kulit tersebut umumnya disebabkan oleh keberadaan radikal bebas dan hal ini dapat dicegah dengan antioksidan. Kulit pisang Kepok (Musa acuminata x balbisiana) mengandung senyawa flavonoid dapat bekerja sebagai antioksidan sehingga memberikan efek proteksi terhadap radiasi ultraviolet. Pada penelitian ini dilakukan pengamatan ketebalan epidermis dan menghitung jumlah melanosit pada kulit mencit (Mus musculus) yang dipaparkan sinar ultraviolet selama 14 hari dengan dosis 60 menit per hari. Bagian kulit terpapar diolesi dengan sediaan ekstrak kulit pisang Kepok 1,5% (P1), ekstrak kulit pisang Kepok 5% (P2), ekstrak kulit pisang Kepok 10% (P3), ekstrak propolis 1,5 % sebagai kontrol positif (K+), dan kontrol negatif tanpa adanya penambahan sediaan ekstrak (K-). Pengamatan perubahan struktur kulit mencit dilakukan secara mikroskopik. Hasil penelitian menunjukkan pemberian ekstrak kulit pisang Kepok 1,5% (P1) paling baik untuk menghambat penebalan epidermis dengan rata-rata ketebalan epidermis 98 μm dan produksi melanosit pada kulit mencit (Mus musculus), yaitu 8,3.AbstractExposure to the skin directly by ultraviolet rays in the long term can cause damage to the skin. The presence of free radicals generally causes skin damage, and antioxidants can prevent it. Kepok banana peel (Musa acuminata x balbisiana) contains flavonoid compounds that can work as antioxidants, protecting against ultraviolet radiation. This study observed the thickness of the epidermis and counted the number of melanocytes in the skin of mice (Mus musculus) exposed to ultraviolet light for 14 days at a dose of 60 minutes per day. The exposed skin was smeared with 1.5% Kepok banana peel extract (P1), 5% Kepok banana peel extract (P2), 10% Kepok banana peel extract (P3), 1.5% propolis extract as a positive control (K+), and negative control without adding extract preparations (K-). Observation of changes in the structure of the mice's skin was carried out microscopically. The results showed that administering 1.5% (P1) Kepok banana peel extract was the best for inhibiting epidermal thickening with an average epidermal thickness of 98 μm and melanocyte production in mouse skin (Mus musculus), namely 8.3.
Potensi Cendawan Xylaria sp. Sebagai Sumber Antioksidan
Authors: Prasetyo Handika Dwi , Listiyowati Sri , Batubara Irmanida
Published: January 2024

AbstrakPencegahan radikal bebas di dalam tubuh dapat dilakukan dengan menggunakan antioksidan. Cendawan Xylaria memiliki kandungan senyawa bioaktif yang berasal dari metabolit sekunder yang berpotensi sebagai sumber antioksidan alami baru. Penelitian ini bertujuan menentukan potensi Xylaria sp. (strain F, D, C) sebagai sumber antioksidan melalui pengukuran aktivitas antioksidan dan kandungan total flavonoidnya. Cendawan ditumbuhkan pada media Potato Dextrose Yeast Extract Broth (PDYEB) dan diinkubasi 14 hari dengan kondisi gelap dan statis. Miselium cendawan digerus dengan bantuan nitrogen cair, kemudian ekstraksi dilakukan menggunakan pelarut metanol sebanyak dua kali ulangan. Penentuan aktivitas antioksidan menggunakan metode 2,2-Diphenyl-1-picrylhydrazyl (DPPH) dan kandungan total flavonoid ditentukan menggunakan metode alumunium klorida (AlCl3) yang dinyatakan ekuivalen kuersetin (QE). Seluruh sampel Xylaria sp. memiliki aktivitas antioksidan yang lemah dan kandungan flavonoid yang juga rendah. Xylaria sp. strain F memiliki aktivitas antioksidan tertinggi sebesar 1915,14 ± 24,73 µg/mL dan Xylaria sp. strain D memiliki kandungan total flavonoid tertinggi sebesar 2,41 ± 0,09 mg QE/g ekstrak. Senyawa flavonoid pada sampel Xylaria sp. tidak menjadi senyawa utama yang menunjukkan aktivitas antioksidannya.AbstractPrevention of free radicals in the body can be done by using antioxidants. Xylaria fungus contains bioactive compounds derived from secondary metabolites that have the potential as a source of new natural antioxidants. This study aims to determine the potential of Xylaria sp. (strains F, D, C) as a source of antioxidants by measuring their antioxidant activity and total flavonoid content. The fungus was grown on Potato Dextrose Yeast Extract Broth (PDYEB) and incubated for 14 days in dark and static conditions. The mycelium of the fungus was crushed with the help of liquid nitrogen, then the extraction was carried out using methanol as a solvent for two repetitions. Antioxidant activity was determined using the 2,2-Diphenyl-1-picrylhydrazyl (DPPH) method and the total flavonoid content was determined using the alumunium chloride (AlCl3) method which is expressed as quercetin equivalent (QE). All samples of Xylaria sp. have the weakest antioxidant activity and lowest flavonoid content. Xylaria sp. strain F had the highest antioxidant activity of 1915,14 ± 24,73 µg/mL and Xylaria sp. strain D had the highest total flavonoid content of 2,41 ± 0,09 mg QE/g extract. The flavonoid compounds in the sample Xylaria sp. did not become the main compound showing antioxidant activity.