bluuebunny/crossref_metadata_2025 huggingface dataset:
Combined Surfactant and Enzyme-Assisted Extraction of Pectin from Hawthorn (Crataegus monogyna Jacq.) Fruits
Authors: Novikova Anastasia , Skrypnik Liubov
Published: January 2022

Introduction. Commercial pectin is usually obtained from apples or citrus fruits. However, some wild fruits, such as hawthorn, are also rich in pectin with valuable nutritional and medical properties. The research objective was to study and improve the process of combined surfactant and enzyme-assisted extraction of pectin from hawthorn fruits.

Study objects and methods. The study involved a 1% solution of Polysorbate-20 surfactant and a mix of two enzymes, namely cellulase and xylanase, in a ratio of 4:1. The response surface methodology with the Box-Behnken experimental design improved the extraction parameters. The experiment featured three independent variables – temperature, time, and solvent-to-material ratio. They varied at three levels: 20, 40, and 60°C; 120, 180, and 240 min; 15, 30, and 45 mL per g. Their effect on the parameters on the pectin yield was assessed using a quadratic mathematical model based on a second order polynomial equation.

Results and discussion. The response surface methodology made it possible to derive a second order polynomial regression equation that illustrated the effect of extraction parameters on the yield of polyphenols. The regression coefficient (R2 = 98.14%) and the lack-of-fit test (P > 0.05) showed a good accuracy of the model. The optimal extraction conditions were found as follows: temperature = 41°C, time = 160 min, solvent-to-material ratio = 32 mL per 1 g. Under the optimal conditions, the predicted pectin yield was 14.9%, while the experimental yield was 15.2 ± 0.4%. The content of galacturonic acid in the obtained pectin was 58.5%, while the degree of esterification was 51.5%. The hawthorn pectin demonstrated a good complex-building ability in relation to ions of copper (564 mg Cu2+/g), lead (254 mg Pb2+/g), and cobalt (120 mg Co2+/g).

Conclusion. Combined surfactant and enzyme-assisted extraction made improved the extraction of pectin from hawthorn fruits. The hawthorn pectin can be used to develop new functional products.
Fermented Milk Beverages Fortified with Soy Protein
Authors: Statsenko Ekaterina , Litvinenko Oksana , Kodirova Galina , Kubankova Galina , Korneva Nadezhda , Pokotilo Olesya
Published: January 2022

Introduction. Fermented milk beverages with various vegetable additives expand the range of functional foods with probiotics, vitamins, and minerals. The research objective was to develop a new technology for fermented milk drinks fortified with soy protein.

Study objects and methods. Heat-treated cow’s milk with Direct Vat Set bacterial starter served as the control sample, while the experimental samples featured fermented milk fortified with soy additives. The soy protein ingredient was obtained from powdered sprouted soybean. Soybeans were pre-germinated in a thermostat at 26°C for 24 h and blanched with steam for 15 min. After that, 1–9% of the soy substance was added to pasteurized milk and fermented at 38–40°C for 6–8 h. The resulting sample was tested for quality indicators and physicochemical composition.

Results and discussion. The best sensory properties belonged to the sample with 5% mass fraction of the soy additive. As a result, the soy-fortified beverages entitled Bifivit and Immunovit had a better nutritional value: protein – by 1.92 and 1.79 g, fat – by 0.77 and 0.75 g, vitamin E – by 0.16 mg, choline – by 23.82 mg, potassium – by 149 mg, phosphorus – by 19 and 22 mg, calcium – by 25 and 24 mg, magnesium – by 22 and 23 mg, respectively. One portion (100 g) of these drinks contained over 15% of recommended daily intake of protein, vitamin B2, potassium, magnesium, calcium, and phosphorus. The content of lactic acid and bifidobacteria remained above the norm (1×108) both in fresh products and by the end of their shelf life.

Conclusion. The article introduces a technology of new functional soy-fortified fermented milk drinks with improved chemical and sensory properties.
Effect of Oat-Based Ingredients on the Quality of Pastry Products
Authors: Shcherbakova Natalia , Misteneva Svetlana , Rudenko Oxana , Kondrat’ev Nikolay , Baskakov Andrew
Published: January 2022

Introduction. Whole grain products can prevent some chronic diseases. Oats and oat-based foods are rich in beta-glucan, which makes them a perfect ingredient for functional foods. The present research objective was to introduce oat-based ingredients into the formulation of sugar cookies and study the quality of the finished product.

Study objects and methods. The study involved various formulations of sugar cookies with different proportions of oat meal and composite flour. Sensory, physicochemical, rheological, structural, and mechanical properties were determined according to standard methods.

Results and discussion. The mass shares of protein, fat, and dietary fiber increased together with the share of oat meal: protein – 11.9–12.5%, fat – 2.3–3.7%, dietary fiber – 4.1–4.5%. The swelling rates were 3.41–4.60, which was higher than in the wheat flour sample (2.94). Oat meal increased the viscosity of the model suspensions from 50 to 500 Pa·s The sample with the biggest share of oat meal had the greatest strength (1700 g). The water absorption also increased (193%): it was 220 when the share of oat meal was 20% and 221% when it was 30%. Oat meal decreased the water activity from 0.360 to 0.290 as its concentration grew.

Conclusion. The optimal amount of oat meal was 30% and that of oatmeal flakes – 10% of the flour amount. The research also defined the effect of oat meal and oat flakes on the composite flour blend, model dough, and sugar cookes. The article introduces a new commercial formulation of sugar biscuits.
Macroeconomic assessment of the environmental quality of economic growth at the regional level
Authors: Panov Andrey
Published: January 2022

The research featured a macroeconomic assessment of the quality of economic growth. The analysis was based on various environmental factors, obtained in the process of strategic environmental assessment of the developmental priorities of the Kemerovo region in 2002–2020. The research objective was to determine the effect of environmental factors on eco-intensity and economic growth in this resource-based region in the context of global and national environmental challenges. The paper presents an overview of the methods of ecological and economic analysis suitable for strategic environmental assessment. The study featured mathematical methods of calculating the economic eco-intensity and the decoupling effect, as well as the model of economic growth developed by P. Victor. The decoupling effect was rather weak for the main types of negative impact, i.e. pollution, waste generation, disturbed lands, etc. The only green decoupling effect was revealed by the volume of contaminated wastewater. P. Victor's extended model showed the predominance of "brown" economic growth, while the increase in the carbon intensity of the gross domestic product for methane coincided with the significant decrease in the economic development of the region. The article also introduces a forecast of the economic development of the Kemerovo region, based on global and national trends of decarbonization. Transition to the use of the best available technologies should reduce the level of eco-intensity and increase the rate of decarbonization, both in the main industries and in methane processing.
Adsorption of phosphorus onto nanoscale zero-valent iron/activated carbon: removal mechanisms, thermodynamics, and interferences
Authors: Adly Adel , Mostafa Nagwan G. , Elawwad Abdelsalam
Published: January 2022

This study investigated removal mechanisms, thermodynamics, and interferences of phosphorus adsorption onto nanoscale zero-valent iron (nZVI)/activated carbon composite. Activated carbon was successfully used as support for nZVI particles to overcome shortcomings of using nZVI include its tendency to aggregate and separation difficulties. A comprehensive characterization was done for the composite particles, which revealed a high specific surface area of 72.66 m2/g and an average particle size of 37 nm. Several adsorption isotherms and kinetic models have been applied to understand the removal mechanisms. Adsorption isotherm is best fitted by Freundlich and Langmuir models, which indicates that the estimated maximum phosphorus adsorption capacity is 53.76 mg/g at pH 4. Adsorption kinetics showed that the chemisorption process behaved according to a pseudo-second-order model. An adsorption mechanism study conducted using the intra-particle diffusion and Boyd kinetic models indicated that the adsorption rate is limited by surface diffusion. A thermodynamic study showed that phosphorus removal efficiency increased as the solution temperature increased from 15 to 37 °C. Finally, the results of an interference study showed that the presence of Ni2+, Cu2+, Ca2+, Na+ cations, nitrate ions (), and sodium acetate improves removal efficiency, while the presence of sulfate ions () and urea reduces removal efficiency.
ON OSCILLATORY INSTABILITY IN A SYSTEM OF TWO IMMISCIBLE LIQUIDS UPON LOCAL HEATING OF THE INTERFACE
Authors: Klyuev Denis S. , IVANOVA Natalia А.
Published: January 2022

Modern methods of controlling the shape of interfacial surfaces of miscible and immiscible liquids, as well as technologies based on them, adaptive liquid optics, or the so-called free-form optics, require a deep understanding of the processes of heat and mass transfer occurring at the interface. These processes have a significant effect on the shape of the surface and the rate of its transition to a stable state, which is the determining criterion for accommodating the optical characteristics of liquid-layer optics. The aim of this work is to study the main modes of thermocapillary convection in a horizontal system of two immiscible liquids. The reason for the occurrence of heat and mass transfer in the system under study was the local heating of the interface with the help of laser radiation. The technique for obtaining information about the change in the curvature of the layer surface as an indicator of the hydrodynamic stability of the system is based on measuring the diameter of the interference pattern formed on a remote screen by a laser beam reflected from the deformed surface of the liquid. Using this method, it was found that one of the systems under consideration (benzyl alcohol — polymethylsiloxane) is characterized by the appearance of hydrodynamic instability of an oscillatory nature, which manifests itself in a change in the shape of both the interface between the two liquids and the free boundary. The distinctive features of the evolution of the detected instability are shown, and an assumption is made about the influence of microbubble clusters, revealed by the method of optical microscopy, as the cause of the onset and damping of oscillations. It is assumed that the movement of bubble clusters by means of thermocapillary flows and capillary drift contributes to the formation of a local difference in interfacial tension, leading to destabilization of the stable deformation of the layer and the transition of the system to a mode of oscillatory instability. The decay times and periods of oscillations are determined depending on the thickness of the upper layer.
AUTOMATIC ROCK IDENTIFICATION FROM CORE PHOTOS USING MODERN MACHINE LEARNING METHODS
Authors: Dyachkov Sergey M. , Yadryshnikova Olga A. , Polyakov Dmitriy V. , Devyatka Nadezhda P. , Chermyanin Pavel I. , Dmitrievskiy Mikhail V.
Published: January 2022

Layer-by-layer description of the core is performed to understand the regularities of the structure of the geological section, predict the development of reservoirs, clarify stratigraphic boundaries and obtain calculation parameters for assessing hydrocarbon reserves. In this case, the name of the breed is one of the key parameters determined in the layer-by-layer description.
This paper presents a comparative analysis of two approaches to determining the breed using machine learning methods: based on graphical identifiers and convolutional neural networks.
The original sample contained photographs of core samples from the Tyumenskaya suite fields (8 fields, 15 wells, more than 2 km of core) under daylight. For the analysis, 4 main classes of rocks (siltstones, mudstones, sandstones, coals) were selected. For these rocks, windows of 5 × 5 cm were formed and compressed to 299 × 299 pixels. The total sample exceeded 90,000 windows: 70% — training sample (60,359 windows) and 30% — test (31,140 windows). The training and test samples contain photographs of core samples from different fields.
The comparison was made between convolutional neural networks (ResNet, ResNeXt, Inception, etc.) and a classifier (such as XGBoost) based on graphic identifiers of two types: color (average color, dominant colors) and texture (entropy, Euler’s number, contrast, dissimilarity, uniformity, energy, correlation). According to the results of the experiments, the model based on convolutional neural networks turned out to be more sensitive to implicit features and made it possible to reduce the error in the weighted average f1-measure with respect to the ensemble of weak classifiers by 12.5% on the test sample even without optimization of hyperparameters.
Thus, we can conclude that the model based on convolutional neural networks is more sensitive to implicit features that are difficult to extract using known graphic identifiers. On the other hand, the approach based on graphic identifiers and an ensemble of weak classifiers can be used without specialized computing power (video cards).
COOLING DOWN OF OIL WHEN THE PIPELINE STOPS IN FROZEN SOIL
Authors: VAKULIN Alexander A. , SCHABAROV Alexander B. , VAKULIN Alexander A.
Published: January 2022

The article presents the formulation and solution of the associated problem of oil cooling when the underground laying oil pipeline stops and the temperature changes in frozen soil in the presence of moss and snow cover on the surface. A physical and mathematical model and an associated computational algorithm for calculating the parameters of oil in a pipeline and soil with covers have been developed. Peculiarities of solidification of oil containing N-fractions of paraffins during heat removal into frozen soil have been studied. In this work, an important solved problem is the approximation of a characteristic diagram of phase equilibrium states during cooling of paraffinic oil in the temperature range from the onset of crystallization of paraffins to the pour point. A feature of the problem being solved is that the temperature field of oil in the pipeline (region A) and the temperature field of the moist soil surrounding the pipeline (region B) have a common border — the pipeline wall, which is assumed to be thin. Through the pipeline wall, the temperature of which is not known in advance, the mutual influence of temperature fields (conjugation) is taken into account. The results of an experimental study of changes in the temperature in the pipeline with time in laboratory conditions are presented. The calculation results are in satisfactory agreement with experimental data on the solidification of high-viscosity paraffinic oil in a model oil pipeline when the oil is cooled from +4.5 to −5.5 °C. On the basis of the physical and mathematical model developed in this article and the coupled algorithm for calculating the parameters of soil and oil, it has been established that in the presence of moss and snow cover, characteristic of the winter conditions of the Middle Ob region of Western Siberia, in an oil pipeline with a nominal diameter of 700 mm, oil freezes in a time of 40 60 hours depending on soil parameters and oil fractional composition.
FEATURES OF PHYSICAL AND MATHEMATICAL MODELING OF OIL AND WATER FILTRATION AT DIFFERENT CRIMPING PRESSURES
Authors: Zagorovskiy Mikhail A. , STEPANOV Sergei V. , Gilmanov Yan I. , Zagorovskiy Alexei A. , Zaitsev Alexei I.
Published: January 2022

The article discusses the features and results of physical and mathematical modeling of filtration experiments on terrigenous and carbonate rock core samples at different crimping pressures. Such studies are necessary to understand the effect of rock pressure on the reservoir properties and relative phase permeability (RP) of reservoir rocks, including from the standpoint of the Digital Core technology, since core tomography is usually performed under atmospheric conditions and data on rock properties are required for reservoir conditions.
The article discusses the features and results of physical and mathematical modeling of filtration experiments on terrigenous and carbonate rock core samples at different crimping pressures. Such studies are necessary to understand the effect of rock pressure on the reservoir properties and relative phase permeability (RP) of reservoir rocks, including from the standpoint of the Digital Core technology, since core tomography is usually performed under atmospheric conditions and data on rock properties are required for reservoir conditions.
The laboratory study of the relative permeability was carried out on composite core models by the method of stationary filtration at crimping pressures of 10 and 20 MPa. Mathematical modeling of filtration experiments was performed in the Eclipse simulator. The distribution of porosity in the hydrodynamic models of the core was set based on data from computed tomography of the core. The distribution of other rock properties (permeability, residual saturations, RPP values at residual saturations) was calculated using generalized dependencies.
It is shown that for terrigenous and carbonate rocks, an increase in pressure leads to different behavior of the RPP functions and fluid mobility. The results of laboratory studies are interpreted from the point of view of processes at the micro level, based on the formation of the nature of the flow and the associated water saturation during deformation of the void space. It is also shown that filtration experiments on core at different rock pressures can be simulated on a hydrodynamic simulator, but at the same time, the study of patterns in the change in model parameters with a change in pressure depends on the presence of patterns in the behavior of rock properties based on the results of physical modeling.
Chemical Constituents of the Roots of Astragalus polycladus var. nigrescens
Authors: Zhang Yu , Yang Han , Dong Xiang , Xiao Chao-Jiang , Jiang Bei
Published: January 2022

A new cycloartane triterpenoid, 24-acetylcyclocantogenin (1), along with five cycloartane
triterpenoids (2-6), eight steroids (7-14) and nine other known compounds (15-23), was obtained from
the methanol extract of roots of Astragalus polycladus var. nigrescens. Their structures were elucidated
based on extensive spectroscopic analysis (1D and 2D-NMR, MS and IR). They were isolated from A.
polycladus var. nigrescens for the first time.
2′,7′-Dichlorofluorescein: Biological, Analytical, and Industrial Progress
Authors: Kousar Shazia , Mudassir Muhammad Ahmad , Bibi Fehmeeda , Irfan Madiha , Alyas Mohammad , Bukhari Syed Waqas , Qadir Salman
Published: January 2022

Abstrack:

Fluorescein derivatives have attracted a great deal of attention for ubiquitous applications
on account of their unique properties. Particularly, the 2′,7′-dichlorofluorescein (DCF) is of paramount
importance in biological, analytical, and industrial fields. Mainly, DCF has been employed as
a reactant in reactive oxygen species (ROS) formation reactions in biological applications. It has
been utilized in oxidative stress and cell spreading measurement. It has been extensively explored to
analyze oxidative, respiratory burst, secretory peroxidase, and multidrug resistance-associated proteins
(MRPs). It has been widely investigated for detecting/quantification of H2O2, glucose, lipid,
cholesterol, other hydroperoxides, and polycationic protamine.
Moreover, it has been applied to differentiate dopamine from ascorbic acid. It has also shown immense
potential in biolabeling, cancer imaging, and drug delivery. Several studies demonstrated the
great promise of DCF as a fluorescent probe for real-time monitoring/quantification of mercury,
cadmium, zinc, arsenite, acetate, fluoride, thiocyanate, azide ions, hydrogen peroxide, ammonia,
ozone, sulfur dioxide, and drug molecules. Furthermore, the use of DCF to manufacture dyesensitized
solar cells and Schottky barrier devices opens up avenues for its industrial applications.
Apart from presenting a comprehensive account of the immense potential of DCF in the areas mentioned
above, the present review also intends to provide insight into its broader future scope for a
myriad of applications to emerge.
role of experiential value in mediate experiential marketing on repurchase intention
Authors: Darmawan Made Harry , Yasa Ni Nyoman Kerti
Published: January 2022

The various types of culinary businesses offered are so diverse such as restaurants, cafes, lounges, and bars. One local restaurant that is well known to the public is MM Juice and Restaurant. An indicator of the success of a company is determined by the intention to repurchase its consumers on an ongoing basis which is one of the factors that MM Juice and Restaurant want to improve. This study aims to explain the role of experiential value in mediating the effect of experiential marketing on repurchase intention. This research was conducted in Denpasar City involving 185 respondents who live in Denpasar with an age range of 18 years and over and have completed high school education. The method used is online purposive sampling via Google Form. The data analysis technique used is a descriptive statistical analysis technique, path analysis, and Sobel test. The results of this study indicate that experiential marketing has a positive and significant effect on experiential value.
Developing high-quality human resources in quang ngai province (Viet Nam) currently
Authors: Quyet Nguyen Thi
Published: January 2022

Currently, developing the high-quality human resources to meet the socio-economic development requirements of Vietnam in general and Quang Ngai province in particular is a very urgent need, is a very urgent need. This is a both fundamental and long-term issue  in order to realize the strong and happy national aspirations. Located in the central key economic region with Dung Quat economic zone whose core is Dung Quat oil refinery, Quang Ngai is developing day by day. Presently, Dung Quat economic zone together with industrial clusters of the province have been creating a huge value of industrial output, especially heavy industry - an important spearhead industry in the process of industrialization, modernization, creating momentum to promote the development of industry and service in the whole region, and play an important role in creating the driving force for the development of the central region. Due to the specific requirements of industries with modern technology, Quang Ngai is required to have highly qualified and skilled human resources. Being well aware of this, Quang Ngai province has paid great attention to the development of high-quality human resources and initially achieved certain achievements over the past time.
determinant of business intelligence systems quality on Indonesian higher education information center
Authors: Murti Galuh Tresna , Mulyani Sri
Published: January 2022

PDDIKTI Feeder as a business intelligence application is used as an information center in higher education, containing master data of each student and lecturer, learning process data, reporting graduate data and lecturer activities in teaching for decision making. Paradoxically, through the empirical data there are many problems in implementing business intelligence systems in private universities, related to the maturity of information technology, data quality and information culture. Addressing this gap, we present a descriptive verification analysis research on 40 private universities in Bandung city, Indonesia, using the Partial Least Square Model. We conclude there is a positive influence of information technology maturity, data quality and information culture on the quality of the business intelligence system.
Structure, meanings and functions make from colors of personal nouns in ede in Vietnam
Authors: Hoat Nguyen Minh , Huyen Nguyen Thi Thanh
Published: January 2022

In linguistics, when studying nouns, specialists often divide them into two large groups, common nouns, and proper nouns. Based on general meaning, common nouns are divided into smaller groups, such as nouns with generalizing meaning, nouns without generalizing meaning. Nouns with generalizing meaning can be divided: nouns of units, nouns of people, nouns of objects, etc. Nouns for people include nouns denoting kinship relations, social relations. These are general nouns of people. They take up a sizeable amount and are an important word class of nouns. Nouns of people indicate not only people but also expressive nuances, cultural expressions of individuals or communities. The article clarifies the characteristics of structures, semantics, and functions as Ede vocative addressing words in Vietnam, thereby explaining the Ede people's cultural characteristics through nouns of people.
PENGUJIAN KONSORSIUM MIKROBA ANTAGONIS UNTUK MENGENDALIKAN PENYAKIT PUSTUL BAKTERI PADA TANAMAN KEDELAI
Authors: Dwirani Novia , Syibli Muhammad Akhid , Aini Luqman Qurata
Published: January 2022

Salah satu penyakit penting yang menyerang tanaman kedelai adalah penyakit pustul daun yang disebabkan oleh bakteri Xanthomonas axonopodis pv. glycines. Penelitian ini bertujuan untuk mengetahui potensi konsorsium mikroba antagonis yang terdiri dari Bacillus subtillis, Pseudomonas fluorescens, serta Trichoderma sebagai agens hayati untuk mengendalikan penyakit pustul daun pada tanaman kedelai yang disebabkan oleh bakteri X. axonopodis pv. glycines. Hasil penelitian menunjukkan bahwa semua perlakuan aplikasi antagonis baik yang berupa konsorsium mikroba antagonis maupun mikroba antagonis tunggal mampu menghambat pertumbuhan bakteri X. axonopodis pv. glycines pada media dalam cawan Petri. Semua perlakuan mikroba antagonis baik tunggal maupun dalam konsorsium juga menekan perkembangan penyakit pustul bakteri pada tanaman kedelai. Kemampuan konsorsium mikroba antagonis dengan konsentrasi 20ml/l, konsorsium mikroba antagonis dengan konsentrasi 30ml/l, mikroba antagonis tunggal B. subtilis, P. fluorescens, dan Trichoderma, setara dengan bakterisida Streptomisin sulfat dalam menekan perkembangan penyakit pustul bakteri pada tanaman kedelai. Perlakuan mikroba antagonis tunggal P. fluorescens dapat meningkatkan tinggi tanaman kedelai.
An Analysis of Optimal Tax Revenue Sharing for Mexico
Authors: Ponce Rodríguez Raúl Alberto , Ponce Rodríguez Benito Alan
Published: January 2022

We develop an analysis that identifies the characteristics of an optimal system of shared tax collection and intergovernmental transfers. Mathematical optimization is used to find the level of taxes and intergovernmental transfers. Formulas for the optimal level of taxes and transfers to subnational governments are characterized. We suggest reforms to intergovernmental transfers to include the costs of tax inefficiency, some tax equalization transfer rules, and the marginal social benefits of local public spending. Future research could include local public spending with regional externalities, migration, and consider a dynamic model. This article proposes an original theoretical model of optimal tax coordination and transfers. The optimal level of taxes and transfers are identified. This paper proposes reforms to the participation formula for subnational governments.
Relaciones de largo plazo entre la política monetaria, el tipo de cambio y el premio al riesgo en México (2003-2018)
Authors: Castro Pérez Judith Jazmín , Cruz Aké Salvador , Durán Saldívar Mario Alejandro
Published: January 2022

El objetivo de esta investigación es estudiar las relaciones de largo plazo entre la política monetaria, el tipo de cambio y el premio al riesgo en la economía mexicana. Mediante la metodología de series de tiempo, modelos ARFIMA y ARFIMAX, con datos diarios de mayo, 2003 a octubre, 2018. Los resultados señalan que las decisiones tomadas por el Banco Central a través de su mecanismo de transmisión (tasa de interés) bajo un objetivo de inflación controlada, envían señales a la economía que impactan en el tipo de cambio, el cual actúa como el canal de transmisión que altera el comportamiento del premio al riesgo de los activos financieros. La recomendación es analizar el impacto que tienen otros mecanismos de política monetaria en el premio al riesgo, la limitación es que sólo se analizaron las relaciones especificas al objetivo, implicando la falta de medición de otros efectos económicos. La originalidad es el análisis de relaciones de largo plazo en la política monetaria mediante modelos fraccionales. En conclusión, se reconoce la existencia de la paradoja del banco central en la economía mexicana.
La hipótesis de convergencia en México: un enfoque de sigma-convergencia débil
Authors: Rodríguez Benavides Domingo , Mendoza González Miguel Ángel , Climent Hernández José Antonio
Published: January 2022

Se analiza la hipótesis de convergencia en México con la prueba relativamente novedosa de sigma–convergencia débil, propuesta por Kong, Phillips y Sul (2019), en el periodo 1940-2019 y en dos subperiodos con la totalidad de las entidades federativas y con grupos formados a partir de su niveles de ingreso, con el fin de determinar si el proceso de liberalización comercial y la entrada en vigor del Tratado de Libre Comercio de América del Norte (TLCAN) promovieron la convergencia regional. Se encuentra que tanto para el primer periodo, como para todo el periodo hay evidencia de –convergencia débil, por el contrario revelan evidencia de divergencia para el segundo periodo. La aplicación de esta prueba en los grupos formados a partir de sus niveles de ingreso contribuye a identificar si algunos de estos grupos puede ser los causantes de la ausencia de convergencia de todas las entidades federativas. No obstante, una limitación de la misma es que puede no conciliar resultados obtenidos para todo el periodo en relación con los de los subperiodos.
El desempeño financiero de la empresa y la composición del consejo de administración
Authors: Berrocal González Adriana María , Domínguez Ortíz Lili , Mariné Osorio Fernando José , Ruiz Fuentes Liliana Raquel
Published: January 2022

Con base en la Teoría de Dependencia de Recursos (TDR) y la Teoría de Agencia (TA), esta investigación tiene por objetivo analizar si existe una relación entre el número y tipo de consejeros (constructo consejo de administración) con respecto a indicadores de desempeño financiero de la empresa con base en ROA, ROE, Margen de Beneficio Neto, ingresos por empleado y riesgo sistemático de mercado-beta (constructo desempeño financiero). Utilizando el método innovador y adecuado para muestras pequeñas PLS-SEM, se crea un modelo teórico basado en la revisión de literatura y un modelo de medición que opera con base en correlaciones múltiples y simultáneas entre las variables seleccionadas. Los resultados muestran la conformación de dos constructos y denotan una relación estadísticamente significativa entre ambos. Se tiene la limitante de ser un análisis exploratorio y transversal. El estudio es original en la aplicación del método estadístico al campo del gobierno corporativo y las finanzas y en la selección de variables. Se concluye que el modelo teórico planteado es eficiente para continuar estudiando los constructos en las empresas.
Using Facebook Advertisements for Women’s Health Research: Methodology and Outcomes of an Observational Study
Authors: Farr Deeonna E , Battle Darian A , Hall Marla B
Published: January 2022

Background

Recruitment of diverse populations for health research studies remains a challenge. The COVID-19 pandemic has exacerbated these challenges by limiting in-person recruitment efforts and placing additional demands on potential participants. Social media, through the use of Facebook advertisements, has the potential to address recruitment challenges. However, existing reports are inconsistent with regard to the success of this strategy. Additionally, limited information is available about processes that can be used to increase the diversity of study participants.

Objective

A Qualtrics survey was fielded to ascertain women’s knowledge of and health care experiences related to breast density. This paper describes the process of using Facebook advertisements for recruitment and the effectiveness of various advertisement strategies.

Methods

Facebook advertisements were placed in 2 rounds between June and July 2020. During round 1, multiple combinations of headlines and interest terms were tested to determine the most cost-effective advertisement. The best performing advertisement was used in round 2 in combination with various strategies to enhance the diversity of the survey sample. Advertisement performance, cost, and survey respondent data were collected and examined.

Results

In round 1, a total of 45 advertisements with 5 different headlines were placed, and the average cost per link click for each headline ranged from US $0.12 to US $0.79. Of the 164 women recruited in round 1, in total 91.62% were eligible to complete the survey. Advertisements used during recruitment in round 2 resulted in an average cost per link click of US $0.11. During the second round, 478 women attempted the survey, and 87.44% were eligible to participate. The majority of survey respondents were White (80.41%), over the age of 55 years (63.94%), and highly educated (63.71%).

Conclusions

Facebook advertisements can be used to recruit respondents for health research quickly, but this strategy may yield participants who are less racially diverse, more educated, and older than the general population. Researchers should consider recruiting participants through other methods in addition to creating Facebook advertisements targeting underrepresented populations.
A Novel Experience Sampling Method Tool Integrating Momentary Assessments of Cognitive Biases: Two Compliance, Usability, and Measurement Reactivity Studies
Authors: Boemo Teresa , Socastro Angela , Blanco Ivan , Martin-Garcia Oscar , Pacheco-Romero Ana Mar , Rodríguez-Carvajal Raquel , Sanchez-Lopez Alvaro
Published: January 2022

Background

Experience sampling methods (ESMs) are increasingly being used to study ecological emotion dynamics in daily functioning through repeated assessments taken over several days. However, most of these ESM approaches are only based on self-report assessments, and therefore, studies on the ecological trajectories of their underlying mechanisms are scarce (ie, cognitive biases) and require evaluation through experimental tasks. We developed a novel ESM tool that integrates self-report measures of emotion and emotion regulation with a previously validated app-based cognitive task that allows for the assessment of underlying mechanisms during daily functioning.

Objective

The objective of the study is to test this new tool and study its usability and the possible factors related to compliance with it in terms of latency and missing responses. Among the compliance predictors, we considered psychological and time-related variables, as well as usability, measurement reactivity, and participants’ satisfaction with the tool.

Methods

We conducted 2 extensive ESM studies—study 1 (N=84; a total of 3 assessments per day for 5 days) and study 2 (N=135; a total of 3 assessments per day for 10 days).

Results

In both studies, participants found the tool highly usable (average usability score >81). By using mixed regression models, we found both common and specific results for the compliance predictors. In both study 1 and study 2, latency was significantly predicted by the day (P<.001 and P=.003, respectively). Participants showed slower responses to the notification as the days of the study progressed. In study 2 but not in study 1, latency was further predicted by individual differences in overload with the use of the app, and missing responses were accounted for by individual differences in stress reactivity to notifications (P=.04). Thus, by using a more extensive design, participants who experienced higher overload during the study were characterized by slower responses to notifications (P=.01), whereas those who experienced higher stress reactivity to the notification system were characterized by higher missing responses.

Conclusions

The new tool had high levels of usability. Furthermore, the study of compliance is of enormous importance when implementing novel ESM methods, including app-based cognitive tasks. The main predictors of latency and missing responses found across studies, specifically when using extensive ESM protocols (study 2), are methodology-related variables. Future research that integrates cognitive tasks in ESM designs should take these results into consideration by performing accurate estimations of participants’ response rates to facilitate the optimal quality of novel eHealth approaches, as in this study.
Mobile App Intervention on Reducing the Myeloproliferative Neoplasm Symptom Burden: Pilot Feasibility and Acceptability Study
Authors: Win Hninyee , Russell Samantha , Wertheim Betsy C , Maizes Victoria , Crocker Robert , Brooks Audrey J , Mesa Ruben , Huberty Jennifer , Geyer Holly , Eckert Ryan , Larsen Ashley , Gowin Krisstina
Published: January 2022

Background

Myeloproliferative neoplasms (MPNs) are a group of myeloid malignancies associated with significant symptom burden. Despite pharmacological advances in therapies, inadequate management of MPN symptoms results in reduced quality of life.

Objective

This study aims to determine the feasibility of a 12-week global wellness mobile app intervention in decreasing MPN symptom burden. The University of Arizona Andrew Weil Center for Integrative Medicine’s global wellness mobile app, My Wellness Coach (MWC), guides patients to improve their health and well-being through facilitating behavior changes.

Methods

Of the 30 patients enrolled in a 12-week intervention, 16 (53%) were retained through the final assessment. Feasibility was assessed by the ease of recruitment, participant adherence, and mobile app acceptability. App acceptability was measured using the user version of the Mobile Application Rating Scale. MPN symptom burden was measured at baseline and 12 weeks after the intervention.

Results

Recruitment was efficient, with the participant goal reached within a 60-day period, suggestive of a demand for such an intervention. Adherence was less than the target within study design (75%), although similar to mobile device app use in other studies (53%). The app was deemed acceptable based on the mean user version of the Mobile Application Rating Scale 3-star rating by participants. Finally, there were statistically significant improvements in several MPN symptoms, quality of life, and total score on the Myeloproliferative Neoplasm Symptom Assessment Form surveys.

Conclusions

Our 12-week intervention with the MWC app was feasible and was associated with a decrease in MPN symptom burden. Further investigation of the MWC app for use as a self-management strategy to reduce the symptom burden in patients with MPN is warranted.
The Cole Relaxation Frequency as a Parameter to Identify Cancer in Lung Tissue: Preliminary Animal and Ex Vivo Patient Studies
Authors: Bogdanowicz Les , Fidaner Onur , Ceres Donato , Grycuk Alexander , Guidetti Martina , Demos David
Published: January 2022

Background

Lung cancer is the world’s leading cause of cancer deaths, and diagnosis remains challenging. Lung cancer starts as small nodules; early and accurate diagnosis allows timely surgical resection of malignant nodules while avoiding unnecessary surgery in patients with benign nodules.

Objective

The Cole relaxation frequency (CRF) is a derived electrical bioimpedance signature, which may be utilized to distinguish cancerous tissues from normal tissues.

Methods

Human testing ex vivo was conducted with NoduleScan in freshly resected lung tissue from 30 volunteer patients undergoing resection for nonsmall cell lung cancer. The CRF of the tumor and the distant normal lung tissue relative to the tumor were compared to histopathology specimens to establish a potential algorithm for point-of-care diagnosis. For animal testing in vivo, 20 mice were implanted with xenograft human lung cancer tumor cells injected subcutaneously into the right flank of each mouse. Spectral impedance measurements were taken on the tumors on live animals transcutaneously and on the tumors after euthanasia. These CRF measurements were compared to healthy mouse lung tissue. For porcine lung testing ex vivo, porcine lungs were received with the trachea. After removal of the vocal box, a ventilator was attached to pressurize the lung and simulate breathing. At different locations of the lobes, the lung's surface was cut to produce a pocket that could accommodate tumors obtained from in vivo animal testing. The tumors were placed in the subsurface of the lung, and the electrode was placed on top of the lung surface directly over the tumor but with lung tissue between the tumor and the electrode. Spectral impedance measurements were taken when the lungs were in the deflated state, inflated state, and also during the inflation-deflation process to simulate breathing.

Results

Among 60 specimens evaluated in 30 patients, NoduleScan allowed ready discrimination in patients with clear separation of CRF in tumor and distant normal tissue with a high degree of sensitivity (97%) and specificity (87%). In the 25 xenograft small animal model specimens measured, the CRF aligns with the separation observed in the human in vivo measurements. The CRF was successfully measured of tumors implanted into ex vivo porcine lungs, and CRF measurements aligned with previous tests for pressurized and unpressurized lungs.

Conclusions

As previously shown in breast tissue, CRF in the range of 1kHz-10MHz was able to distinguish nonsmall cell lung cancer versus normal tissue. Further, as evidenced by in vivo small animal studies, perfused tumors have the same CRF signature as shown in breast tissue and human ex vivo testing. Inflation and deflation of the lung have no effect on the CRF signature. With additional development, CRF derived from spectral impedance measurements may permit point-of-care diagnosis guiding surgical resection.
Educators' Perspectives on Integrating Technology Into Sexual Health Education: Implementation Study (Preprint)
Authors: Decker Martha J , Harrison Salish , Price Melisa , Gutmann-Gonzalez Abigail , Yarger Jennifer , Tenney Rachel
Published: January 2022

BACKGROUND

In the last decade, the use of technology-based sexual health education has increased. Multiple studies have shown the feasibility of technology-based interventions, while a subset has also shown efficacy in improving youths’ sexual health outcomes such as increased condom use and knowledge. However, little is known about health educators’ experiences in integrating technology to augment sexual health curricula.

OBJECTIVE

The purpose of this study was to assess the perceptions and experiences of health educators regarding the incorporation of technology into a sexual health education program designed for underserved youth in Fresno County, California, and to identify facilitators and challenges to incorporating technology into the in-person curriculum.

METHODS

This implementation study used data collected as part of a cluster randomized controlled trial to evaluate In the Know (ITK), an in-person sexual health education curriculum that includes technology-based content, such as a resource locator, videos, and games, which can be accessed through a mobile app or website. Data from implementation logs from each cohort (n=51) and annual interviews (n=8) with health educators were analyzed to assess the health educators’ experiences using the technology and adaptations made during the implementation.

RESULTS

The health educators reported that technological issues affected implementation to some degree: 87% of the time in the first year, which decreased to 47% in the third year as health educators’ familiarity with the app increased and functionality improved. Technology issues were also more common in non–school settings. Successes and challenges in 3 domains emerged: managing technology, usability of the ITK app, and youth engagement. The health educators generally had positive comments about the app and youth engagement with the technology-based content and activities; however, they also noted certain barriers to adolescents’ use of the mobile app including limited data storage and battery life on mobile phones.

CONCLUSIONS

Health educators require training and support to optimize technology as a resource for engaging with youth and providing sensitive information. Although technology is often presented as a solution to reach underserved populations, educational programs should consider the technological needs and limitations of the participants, educators, and settings.

INTERNATIONAL REGISTERED REPORT

RR2-10.2196/18060
A Novel Tool for Real-time Estimation of Epidemiological Parameters of Communicable Diseases Using Contact-Tracing Data: Development and Deployment (Preprint)
Authors: Silenou Bernard C , Verset Carolin , Kaburi Basil B , Leuci Olivier , Ghozzi Stéphane , Duboudin Cédric , Krause Gérard
Published: January 2022

BACKGROUND

The Surveillance Outbreak Response Management and Analysis System (SORMAS) contains a management module to support countries in their epidemic response. It consists of the documentation, linkage, and follow-up of cases, contacts, and events. To allow SORMAS users to visualize data, compute essential surveillance indicators, and estimate epidemiological parameters from such network data in real-time, we developed the SORMAS Statistics (SORMAS-Stats) application.

OBJECTIVE

This study aims to describe the essential visualizations, surveillance indicators, and epidemiological parameters implemented in the SORMAS-Stats application and illustrate the application of SORMAS-Stats in response to the COVID-19 outbreak.

METHODS

Based on findings from a rapid review and SORMAS user requests, we included the following visualization and estimation of parameters in SORMAS-Stats: transmission network diagram, serial interval (SI), time-varying reproduction number R(t), dispersion parameter k, and additional surveillance indicators presented in graphs and tables. We estimated SI by fitting lognormal, gamma, and Weibull distributions to the observed distribution of the number of days between symptom onset dates of infector-infectee pairs. We estimated k by fitting a negative binomial distribution to the observed number of infectees per infector. Furthermore, we applied the Markov Chain Monte Carlo approach and estimated R(t) using the incidence data and the observed SI computed from the transmission network data.

RESULTS

Using COVID-19 contact-tracing data of confirmed cases reported between July 31 and October 29, 2021, in the Bourgogne-Franche-Comté region of France, we constructed a network diagram containing 63,570 nodes. The network comprises 1.75% (1115/63,570) events, 19.59% (12,452/63,570) case persons, and 78.66% (50,003/63,570) exposed persons, including 1238 infector-infectee pairs and 3860 transmission chains with 24.69% (953/3860) having events as the index infector. The distribution with the best fit to the observed SI data was a lognormal distribution with a mean of 4.30 (95% CI 4.09-4.51) days. We estimated a dispersion parameter k of 21.11 (95% CI 7.57-34.66) and an effective reproduction number R of 0.9 (95% CI 0.58-0.60). The weekly estimated R(t) values ranged from 0.80 to 1.61.

CONCLUSIONS

We provide an application for real-time estimation of epidemiological parameters, which is essential for informing outbreak response strategies. The estimates are commensurate with findings from previous studies. The SORMAS-Stats application could greatly assist public health authorities in the regions using SORMAS or similar tools by providing extensive visualizations and computation of surveillance indicators.