bluuebunny/crossref_metadata_2025 huggingface dataset:
Modelo de inteligencia artificial y aprendizaje automático para la predicción espacial y temporal de eventos de sequía en el departamento del Magdalena, Colombia.
Authors: Herrera Posada Daissy Milenys , Aristizábal Edier
Published: July 2024

Introducción— La sequía es uno de los fenómenos hidrometeorológicos más críticos por sus impactos en la sociedad. A pesar de que Colombia es un país tropical, existen zonas del territorio que presentan periodos de sequía, lo que ocasiona importantes perjuicios económicos.
Objetivo— Debido a los recientes avances en cuanto a las resoluciones espaciales y temporales de la teledetección, y a las técnicas de inteligencia artificial, es posible desarrollar modelos de aprendizaje automático apoyados en información histórica.
Metodología— En este estudio se construyó un modelo clasificador de Bosque Aleatorio (RF) y Árbol de Decisión en Bolsa (DTC) para realizar la predicción espacial y temporal de sequía en el departamento del Magdalena utilizando las siguientes características: Índice de Vegetación de Diferencia Normalizada (NDVI), temperatura de la superficie terrestre (LST), precipitación, Índice de Agua de Diferencia Normalizada (NDWI), Índice de Sequía Multibanda Normalizada (NMDI), evapotranspiración (ET), humedad superficial del suelo (SSM), humedad subsuperficial del suelo (SUSM), Índice ENSO Multivariado (MEI), Índice de Oscilación del Sur (SOI) e Índice del Niño Oceánico (ONI).
Resultados— Para el etiquetado, que permite entrenar y evaluar el modelo, se utilizó el Índice de Precipitación Estandarizado (SPI) para identificar los eventos de sequía.
Conclusiones— La implementación del modelo desarrollado puede permitir a las entidades gubernamentales tomar acciones para mitigar los impactos generados por sequías recurrentes en sus territorios.
Clasificación de las imágenes de satélite utilizadas en el Catastro Ambiental Rural (REC): un estudio de caso en el municipio de Parobé - RS
Authors: De Medeiros Diego , Muller Rubens , De Nardin Dionara , Dos Santos Dafne 
Published: July 2024

Introducción: A partir de la supresión histórica de la vegetación nativa para otro tipo de uso del suelo (agricultura, ganadería, minería) y con el avance de la geotecnología, se hizo cada vez más importante planificar racionalmente la ocupación y el uso territorial. En este contexto surge el CAR (Registro Ambiental Rural) como mecanismo de promoción de la sustentabilidad ambiental, sancionado por el Nuevo Código Forestal Brasileño (Ley 12.651 / 2012). Objetivo­: De esta manera, esta investigación tiene como objetivo evaluar cómo las imágenes utilizadas para la generación de la base de homologación CAR, en referencia a los años 2008 y 2011, son eficaces para la cartografía ambiental, analizando el municipio de Parobé, en Rio Grande do Sul. Metodología: Las imágenes de análisis temporal, utilizando el distrito de Parobé como caso de estudio, se dividieron en dos grupos. El primero comparó imágenes de los años 2008 y 2011 (como sancionado en el Código Forestal) y el segundo grupo analizó imágenes de 1985 y 2015 (para las cuales había una mayor cobertura para fines de comparación). Resultados: Los resultados mostraron que entre los años de 2008 y 2011 las áreas perturbadas de Parobé disminuyeron un 1%, ya que las áreas con vegetación nativa crecieron un 11% en este período. Entre 1985 y 2015 hubo una disminución del 6% en las áreas perturbadas y las áreas de vegetación nativa se mantuvieron en ambos años ocupando el 21% de la ciudad. Conclusiones: La CAR es de extrema importancia para la sociedad, pues facilita el mapeo de las propiedades rurales, ayuda a controlar la deforestación y de vegetación autóctona cercana a cero en 30 años.
Phytochemical potential of berries: An overview
Authors: Maurer Talison Roberto , Tonello Carolina , Machado Bianca , Trentin Thomas , Bertol Charise , Lângaro Nadia , Chiomento José Luís
Published: July 2024

Introduction: Phytochemicals, or secondary metabolites, present in small fruits are responsible for improving the health of consumers when included in the daily diet. All edible forms of berries are considered safe functional foods because they have nutritional properties and therapeutic potential. Objective: Therefore, this narrative review aims to analyze the state of the art on the phytochemical potential of the six main small fruits (blackberry, physalis, raspberry, blueberry, strawberry and grape), to gather information on the application of strategies to obtain berries with higher concentrations of biomolecules and to present the benefits of phytochemicals to the consuming public. Methodology: In the first stage of this narrative review, the cultivation scenario of these six main berries is contextualized. Subsequently, a temporal metasynthesis on berry phytochemicals is performed. In the last part of this review, we detail the biomolecule profile of blackberry, physalis, raspberry, blueberry, strawberry and grape and focus on their action against diseases. Results: The consumption of these six berries triggers anti-diabetic, anti-inflammatory, anti-cancer, anti-aging, anti-obesity, anti-microbial, anti-ulcer and radioprotective, neuroprotective and glucoregulatory actions. Despite scientific and clinical evidence on the positive effects of small fruit consumption on human health, their consumption remains low. Conclusions: The creation of public policies will contribute to improve the scenario of berry intake because it will involve the entire small fruit production chain: scientists, producers, food and pharmaceutical industries, and consumers.
Diversity and Free Expression in Higher Education
Authors: Young Jeremy , Celestine-Donnor Neijma , Allain Jacqueline
Published: July 2024

Across the United States today, college campuses face two major distinct but interrelated challenges. The first is a legislative threat. Since 2021, state legislatures have enacted 15 laws or policies in 11 states that directly undermine university autonomy and academic freedom. As of this writing, 119 legislative restrictions on higher education have been introduced in 34 states since 2021, and there are now 14 states with such a legislative or policy restriction. The second threat has to do with how university administrators and other campus stakeholders respond to political tensions on campus in a manner that upholds both the prerogatives of inclusivity and robust protections for academic freedom. This article examines these two challenges in tandem, offering guidelines for how to champion academic freedom and free expression while simultaneously fostering inclusive campus communities. Both goals, we argue, are crucial to upholding higher education’s democratic mission.
Changes of the peripapillary vascular parameters in premature infants without retinopathy of prematurity using U-net segmentation
Authors: Liu Shuai ,   School of Information Science and Technology, University of Science and Technology of China, Hefei 230022, Anhui Province, China; Eye Institute, Affiliated Hospital of Nantong University, Medical School of Nantong University, Nantong 226006, Jiangsu Province, China, Ma Cui-Xia , Huang Liu-Hui , Li Bin ,   Anhui Province Maternity and Child Health Hospital, Maternity and Child Health Hospital Affiliated to Anhui Medical University, Hefei 230001, Anhui Province, China,   Department of Ophthalmology, Tenth People’s Hospital Affiliated with Shanghai Tongji University School of Medicine, Shanghai 200072, China,   School of Information Science and Technology, University of Science and Technology of China, Hefei 230022, Anhui Province, China
Published: July 2024

AIM: To quantitatively assess the changes in mean vascular tortuosity (mVT) and mean vascular width (mVW) around the optic disc and their correlation with gestational age (GA) and birth weight (BW) in premature infants without retinopathy of prematurity (ROP).
METHODS: A single-center retrospective study included a total of 133 (133 eyes) premature infants [mean corrected gestational age (CGA) 43.6wk] without ROP as the premature group and 130 (130 eyes) CGA-matched full-term infants as the control group. The peripapillary mVT and mVW were quantitatively measured using computer-assisted techniques.
RESULTS: Premature infants had significantly higher mVT (P=0.0032) and lower mVW (P=0.0086) by 2.68 (104 cm-3) and 1.85 μm, respectively. Subgroup analysis with GA showed significant differences (P=0.0244) in mVT between the early preterm and middle to late preterm groups, but the differences between mVW were not significant (P=0.6652). The results of the multiple linear regression model showed a significant negative correlation between GA and BW with mVT after adjusting sex and CGA (P=0.0211 and P=0.0006, respectively). For each day increase in GA at birth, mVT decreased by 0.1281 (104 cm-3) and for each 1 g increase in BW, mVT decreased by 0.006 (104 cm-3). However, GA (P=0.9402) and BW (P=0.7275) were not significantly correlated with mVW.
CONCLUSION: Preterm birth significantly affects the peripapillary vascular parameters that indicate higher mVT and narrower mVW in premature infants without ROP. Alterations in these parameters may provide new insights into the pathogenesis of ocular vascular disease.
Conocimiento y práctica del autoexamen de mama en la detección precoz de cáncer en mujeres de Bogotá, Colombia
Authors: Fajardo Zapata Alvaro Luis
Published: July 2024

Introducción. La autoexploración mamaria, es una prueba de tamizaje que no disminuye la mortalidad por cáncer, pero permite que las mujeres conozcan la anatomía de sus mamas para que puedan detectar cualquier anormalidad y la informen de inmediato a su entidad de salud. Objetivo. Identificar los conocimientos y prácticas sobre autoexamen de mama en la detección precoz de cáncer en mujeres bogotanas. Materiales y métodos. Estudio descriptivo transversal realizado a través de una encuesta a las participantes del estudio. Resultados. Se encontró que el 87% de las participantes tenían conocimiento sobre qué es, y en qué consiste el auto examen de mama. Se evidenció relación entre la realización del auto examen de mama y la edad (Chi2 = 20.347 p = 0.0024), el nivel educativo (Chi2 = 13.81 p = 0.0079) y los antecedentes de cáncer de esta glándula en las mujeres participantes en el estudio (Chi2 = 10.15 p = 0.0062). Conclusiones. Es necesario insistir en la educación a las mujeres sobre la importancia de la realización del autoexamen de mama, pero hay que poner especial énfasis en recalcar la técnica, para que el resultado de dicha práctica sea eficaz.
Dynamics of Thought in the Fiqh of Civilization Halaqah at Pesantren Affiliated with Nahdlatul Ulama (NU) in Yogyakarta
Authors: Fathorrahman  , A Hashfi Luthfi  , Riyanta  , Ach Fatayillah Mursyidi
Published: July 2024

This paper explains the dynamics of thought in the Halaqah Fikih Peradaban (Fiqh of Civilization Halaqah, HFP) at pesantren (Islamic boarding school) ideologically affiliated with NU. The spirit of fiqh contextualization developed in the Fiqh of Civilization Halaqah is a key idea of PBNU in initiating civilization fiqh as a new approach to understanding and studying Islamic heritage. This paper elaborates on two aspects. First, why PBNU initiated the Fiqh of Civilization Halaqah and how the dynamics of thought occur within it. Second, how pesantren affiliated with NU discuss one of the main focuses of the Fiqh of Civilization Halaqah related to nationality and statehood. The authors use the theory of Islamic Law Sociology to explain the reciprocal relationship between the socio-religious topics discussed in the Fiqh of Civilization Halaqah and the dynamic and critical way of thinking. This paper uses qualitative research. The primary data was obtained through interviews with several sources and five caretakers who conducted the Fiqh of Civilization Halaqah in five pesantrens. Supporting data was obtained from documents and other news sources that review the Fiqh of Civilization Halaqah. The research results show that the reason for the Fiqh of Civilization Halaqah initiated by PBNU is to create a discourse space for contextualizing progressive fiqh understanding and developing a dynamic way of thinking. Through this approach, fiqh can be used as an inclusive perspective in understanding social change and the development of the times. This study also shows that the theme of nationality and statehood (fiqh siyāsah) discussed in the Fiqh of Civilization Halaqah in five Pondok Pesantren (Islamic boarding school) promotes dynamic and progressive thinking while critiquing fiqh siyāsah studies limited to the khilāfah. This attitude aligns with the spirit of civilization fiqh initiated by PBNU, which emphasizes a dialectical perspective in studying Islamic heritage.
The King’s Decree: Integration of Customary Law and Islamic Law in the Clove Lease Agreement
Authors: M. Ali Rusdi  , Pradana Syafa'at Anugrah , Rustam Magun Pikahulan  , Faisal Nur Shadiq Shabri  , Dirga Achmad
Published: July 2024

This study examines the impact of the king’s decree on creation of legal products in Iha Village, Maluku. In Iha, legal products are primarily in the form of village regulations that serve as the foundation for government activities within each village. However, Iha distinguishes itself by utilising the king’s decree. This research employs an empirical juridical approach with a socio-legal perspective, which involves examining the legal realities within society and comparing them with applicable positive law. The study finds that the community views the king’s decree as customary decision that must be adhered to, thereby granting the king absolute, as in a case of authority in the execution of the clove lease agreements. Unlike the other village, Iha follows a different procedure for conduction clove lease agreements, as determined by the king’s decree. In addition, the king’s order is also used as a guiding principle for the preservation of local culture and environmental sustainability through the application of local laws in social cultural, and environment contexts. This research can assist the government in formulating draft laws and regulations pertaining to customary law.
Prevalencia y factores asociados a la sobrecarga percibida en cuidadores familiares de un municipio en Boyacá
Authors: Espitia Nicole , Salazar Montes Ana María
Published: July 2024

Se considera cuidador a la persona que presta ayuda permanente en las actividades de la vida diaria a un individuo dependiente. El cuidado permanente y por largo tiempo genera consecuencias negativas en la salud física y mental, la economía y el área social del cuidador, ocasionando el desarrollo del síndrome de sobrecarga. Si bien, en Colombia se han realizado estudios alrededor de esta enfermedad, en el municipio de Samacá en Boyacá es la primera vez que se analiza. Este estudio determinó la prevalencia general del síndrome de sobrecarga y su relación con factores sociodemográficos y de funcionalidad familiar. El estudio aplico un diseño cuantitativo de corte descriptivo. La muestra estuvo compuesta por 59 cuidadores familiares, a quienes se les evaluó el grado de sobrecarga con el instrumento Zarit. Se realizó un análisis de correlación, modelos lineales generales que fueron evaluados a través de 1000 replicaciones en un bootstrap del mejor modelo del dredge. Se encontró una prevalencia de sobrecarga de 72% y se relacionó con el estado civil, el apoyo familiar y el nivel de dependencia de la persona a cargo. El 91.5% fueron mujeres con escolaridad incompleta bajos ingresos y sin asesoramiento en autocuidado o en cuidado de otros. Los hallazgos indican una escasa atención de este síndrome, una afectación importante de la salud percibida y factores sociodemográficos relacionados. Se refleja la urgencia del acompañamiento a este grupo de cuidadores basado en un enfoque diferencial y la exploración profunda de factores socioculturales que puedan estar incidiendo en la alta prevalencia de sobrecarga.
Encefalitis aguda diseminada en paciente pediátrico: reporte de caso
Authors: Rincón Ardila Osskar Iván , Manrique Flores María Fernanda , Beltrán Nuño José Ignacio
Published: July 2024

Introducción: La encefalomielitis aguda diseminada es una enfermedad desmielinizante aguda del sistema nervioso central, generalmente se relaciona con una infección viral o inmunización; además se asocia a encefalopatía aguda y síntomas neurológicos multifocales. Presentación del caso: Se trata de escolar de sexo femenino sin antecedentes patológicos de importancia ni evidencia de inmunizaciones previas al padecimiento, con cuadro de intolerancia a la vía oral y datos de somnolencia además de presencia de convulsiones y cambios en el comportamiento durante estancia en el servicio de urgencias, con deterioro del estado de conciencia, por lo que requiere manejo avanzado de la vía área y por clínica valorada por el servicio de Neurología. Este último solicita resonancia magnética y se encuentra presencia de múltiples lesiones hiperintensas que involucra sustancia blanca redonda de bordes bien delimitados. Por lo anterior y por evolución clínica, se inicia esquema con esteroides y por no respuesta clínica recibe manejo con inmunoglobulina intravenosa, posteriormente con recuperación gradual de la sintomatología motora, y se envía a seguimiento en la consulta externa con el servicio de neurología. Conclusión: Esta patología constituye un dilema diagnóstico desde la etapa inicial de los síntomas, el padecer esta enfermedad no diagnosticada o no tratada de manera adecuada tiene mayor riesgo de secuelas devastadoras, aunque la parte neurocognitiva es favorable. Por lo anterior, siempre se debe tener en cuenta entre los diagnósticos diferenciales de pacientes con patología del sistema nervioso central con antecedentes de inmunizaciones e infecciones en las últimas 2 semanas.
Cuidado enfermero y calidad de atención integral a la población LGBTI/OSIGD
Authors: Escobar Escobar María Beatriz , Fernández Rincón Carmen Aydé , Henao Buriticá Adiela
Published: July 2024

Introducción investigación realizada para la universidad del Quindío con el objetivo de sistematizar los resultados de estudios relacionados con el cuidados enfermero a la población LGBTI/OSIGD con las publicaciones realizadas en ingles, portuges y español en diferentes paises de europa, norte , centro y sur america, la primera devela las percepciones de los funcionarios de la salud y el contexto sociocultural del cuidado enfermero a este grupo de usuarios y pacientes Objetivo: Sistematizar los hallazgos de los estudios publicados sobre los cuidados de enfermería a la población LGBTI/OSIGD. Método: Revisión sistemática que sigue una guía de ocho pasos: determinar el propósito de  revisión; protocolo y formación; búsqueda de literatura; cribado para  inclusión; evaluación de calidad; extracción de datos; síntesis de estudios y escritura de la reseña. permiten seguir las fases de planificación, desarrollo y reporte de la revisión sistemática. Se partió del planteamiento de la pregunta:  ¿Existen publicaciones científicas sobre los cuidados que enfermería y atencion integral  prestados a la población LGBTI/OSIGD, y cuál es su calidad investigativa? en el período de 2018 a 2022, el estudio se apoya en dos estrategias para medir la cantidad de publicaciones y el cumplimiento de requisitos minimos en cuanto a estructura y organización el QUADAS-2 y el CONSORT. Resultados: se develan las percepciones de los funcionarios de la salud y el contexto sociocultural del cuidado enfermero, describe de que manera se producen ciertos codigos y dispositivos de estigmatización discriminación y exclusión y examina la disparidad en la atención en salud y política pública
Accelerated forming of nickel-cadmium battery by asymmetrical current
Authors: Smetankin G. P. ,   All-Russian Research and Design Institute of an Elektrovozostroyeniye (JSC VELNII), Matekin S. S. , Burdyugov A. S. , Plokhova T. V. ,   All-Russian Research and Design Institute of an Elektrovozostroyeniye (JSC VELNII),   All-Russian Research and Design Institute of an Elektrovozostroyeniye (JSC VELNII),   All-Russian Research and Design Institute of an Elektrovozostroyeniye (JSC VELNII)
Published: July 2024

Research results of accelerated forming of nickel-cadmium and battery cell by asymmetrical current are given. The comparative data on the forming by directive current are given. The chosen mode of forming by asymmetrical current has allowed to reduce cycle quantity and total molding time by factor of 3 at smaller rate of gas evolution and heat in comparison with the forming mode by directive current. Control of battery self-discharge confirmed preservation of required battery performances at forming by asymmetrical current.
Studying of processes of allocation of oxygen and hydrogen on lead-antimony and lead-calcium alloys
Authors: Inozemtseva E. V. ,   Saratov State University, Burashnikova M. M. , Kazarinov I. A. ,   Saratov State University,   Saratov State University
Published: July 2024

Influence of concentration of antimony, tin, cadmium in lead-antimony alloys, also calcium, silver and barium in lead-calcium alloys for speed of allocation of hydrogen and oxygen was studied. It is shown, that alloying lead-antimony alloys cadmium or tin increases overpotential of allocation of hydrogen. The Introduction of cadmium in an alloy also increases overpotential of allocation of oxygen. Tin, on the contrary, causes decrease in overpotential of allocation of oxygen. The increase in concentration of calcium in lead-calcium alloys raises overpotential of allocation of hydrogen, but leads to decrease in overpotential of allocation of oxygen. Alloying lead-calcium alloys silver or barium leads to insignificant reduction of overpotential of allocation of hydrogen, but the rate of allocation of oxygen is thus close to rate of allocation of oxygen on a lead electrode.
Familial Mediterranean Fever Triggered by Menstruation – A Case Report from Zambia
Authors: Maksoud Gamal , Nyirenda Christopher
Published: July 2024

Familial Mediterranean Fever (FMF) is an autoinflammatory autosomal-recessive disorder that is characterized by recurrent attacks of abdominal pains, fevers and serositis. It is highly prevalent among people from the Mediterranean basin including Arabs and Turks. However, due to the increase in migration worldwide, we start to recognize cases of FMF outside the Mediterranean region. We present the case of a 27-year-old Lebanese female residing in Zambia whose recurrent attacks constantly coincided with her menstruation. Due to the rarity of occurrence of FMF in regions such as Zambia, the coming up with the diagnosis was delayed and unnecessary interventions such as exploratory laparotomy were done. This case aims to highlight the importance of considering FMF and its potential triggers especially menstruation by the healthcare providers in non-Mediterranean areas to ensure timely recognition and management to avoid serious future complications such as amyloidosis.
Relevance of the Socialization Process in the Brazilian Public Sector: A Review
Authors: Aylmer Roberto , Aylmer Mariana , Dias Murillo
Published: July 2024

This article explores the socialization process in companies through an extensive literature review. Socialization refers to how new employees are integrated into the company culture. This process can take many forms, including orientation sessions, training programs, mentorship arrangements, and team-building activities. The primary goal of socialization is to help new employees understand the company's values, goals, and expectations. Additionally, it aims to facilitate building relationships with colleagues. In conclusion, a successful socialization process can lead to greater job satisfaction, increased productivity, and stronger team cohesion, which is helpful to scholars, human resource managers, and other practitioners.
Effect of sugarcane bagasse biochar on soybean germination and initial growth
Authors: Souza Lorrana Zelia Martins de , Silva Halax Duart Martins , Alcantara Giovanni Uema , Pinto Bruna Cristina , Carillo Adriana Duneya Diaz , Ferreira Osania Emerenciano , Costa Gustavo Henrique Gravatim , Machado Alan Rodrigues Teixeira
Published: July 2024

Biochar is known as an excellent soil conditioner and a powerful carbon sequestration tool. However, to expand its use, it is necessary to understand potential adverse effects. To better address this issue, biochar was prepared from sugarcane bagasse. The effect of biochar on the germination of soybean seeds was evaluated, and a greenhouse experiment was conducted to assess the response of soybean seedlings to biochar application at different rates (CK, 0% w/w; BC1, 1% w/w; BC3, 3% w/w; and BC5, 5% w/w). Thirty days after sowing, the growth parameters, soil physicochemical attributes, and microbiota were evaluated. The biochar exhibited a low O/C ratio (0.18) and an irregular porous surface, which promoted improvements in the soil’s physical, chemical, and biological attributes. Moreover, no phytotoxic effects were detected in the germination tests for application rates up to 50 t/ha. The results of soybean cultivation revealed that, compared with the CK treatment, the BC3 and BC5 treatments significantly increased the fresh mass of the aerial parts of the plants by 64% and 86%, respectively. These treatments also significantly increased the fresh mass of the root system by 23% and 423%, respectively. These results highlight the potential of biochar in promoting early soybean development.
La exégesis patrística en la interpretación de la Biblia: una reflexión sobre sus acercamientos y métodos
Authors: Cardona Ramírez Hernán ,   Pontificia Universidad Javeriana, Restrepo-Zapata Juan-David ,   Universidad de Antioquia
Published: July 2024

La exégesis patrística es un enfoque de interpretación bíblica, basado en los escritos de los Padres de la Iglesia, que abarca casi siete siglos, desde el siglo I d. C. hasta el VIII d. C. Ha desempeñado un papel fundamental en las tradiciones teológica, histórica y hermenéutica del cristianismo. Este enfoque se caracteriza por una interpretación sincrónica de las Escrituras, considerando tanto su dimensión textual final, como su contexto cultural e histórico. A pesar de su importancia, en el pasado la exégesis patrística se mantuvo en segundo plano en comparación con los métodos históricos y críticos. Sin embargo, ha habido un renovado interés en la exégesis patrística y su diálogo con la exégesis histórica y crítica, así como con las ciencias del lenguaje y la filosofía hermenéutica. Esta investigación se centra en la evolución de la exégesis patrística en los últimos 30 años, considerando su relación con los métodos históricos y críticos, las ciencias del lenguaje y su contribución a la comprensión sincrónica de la Sagrada Escritura. Además, se examinan las relaciones intertextuales en la Biblia y se resalta la importancia de una interpretación personal y comunitaria de las Escrituras, demostrando que la exégesis patrística no solo es relevante para la teología, sino también para un corpus robusto de disciplinas.
The Theodosian Family, Bishop Leo I of Rome, and their competition for piety through their correspondence
Authors: Kooijman Marijke
Published: July 2024

This article investigates the entreaties sent to the Eastern Roman emperor Theodosius II and his elder sister Pulcheria by their Western imperial family members Valentinian III, Galla Placidia and Licinia Eudoxia on behalf of Bishop Leo I of Rome on 22 February 450, and Theodosius’ replies. Instead of focusing on the outcome of this diplomatic correspondence, it analyzes the rhetoric of each letter and compares the arguments used with Bishop Leo’s own letters on this matter to the Eastern imperial court. It is argued that Theodosius and his family could come to contrasting conclusions despite their shared cultural framework of decision-making because they all claimed to act in accordance with Bishop Leo’s wishes. Moreover, this article contends that the entreaties of Valentinian, Galla Placidia and Licinia Eudoxia, albeit prompted and inspired by Leo’s affectionate plea, should also be read as testimonies to their individual interests. Whereas Valentinian and Galla Placidia sought to enhance the status of the city of Rome, Licinia Eudoxia tried to reinforce her personal influence over her father. In an appendix, finally, this article offers the first full English translation of the seven letters under discussion. Thus, it offers new insights in the processes of political decision-making around the Church councils of the mid-fifth century, and discloses an understudied yet unique case of imperial family correspondence.
Descubriendo historias de diseño: nuevas propuestas metodológicas para el estudio de los objetos
Authors: Alfaro María Regina , Hernández Vega de Villagrán Kenia Guisela , Mendoza Valladares Astrid Rocío
Published: July 2024

El presente artículo comparte un innovador enfoque desarrollado por diseñadoras-historiadoras para analizar sistemáticamente las interconexiones entre objetos, cultura, historia y lugares.
Contrastes de la artesanía como componente cultural en la arquitectura patrimonial y la contemporánea de Guatemala
Authors: Alonso Ramírez America
Published: July 2024

El valor de lo artesanal, estimado como un elemento arquitectónico de representación cultural y con objetivo estético, se ha transformado con el tiempo.
Numerical simulation of non-stationary regime of a submerged combustion setup operation
Authors: Demin Vitaly A. , Kostyrya Alexey V.
Published: July 2024

Relevance. The need to evaporate large quantities of brines at potash industry enterprises. Evaporation of brines in surface evaporators is difficult due to the encrustation of heat exchange surfaces by salt deposits. Therefore, such evaporation is most expedient to be carried out in submerged combustion apparatuses, since they do not contain heat-transmitting surfaces. However, in this type of apparatus, malfunctions may occur due to uncontrolled solid phase deposition. At the moment, the dynamics of the solid phase in submerged combustion devices is poorly studied. This study is part of a scientific program aimed at a comprehensive review of the laws of motion of solid particles in submerged combustion apparatuses. Aim. To study the hydrodynamic processes in the submerged combustion setup in the time interval corresponding to the beginning of its operation; describe the patterns of solid phase motion as a function of time. Object. Laboratory setup of submerged combustion. A simplified model of the thermal mode of operation without the subsequent transition of the liquid phase to steam is analyzed. Methods. The study was conducted by numerical experiment. The hybrid finite volume method was used in simulation in combination with the technology of the finite element method. The multiphase system was considered as two coexisting subsystems: gas–liquid and liquid–solid. Results. The paper considers the final time interval of the setup operation. It is found that during the time under consideration, a stationary mode of solid particle deposition is achieved. The authors have detected liquid flow velocity oscillations, leading to fluctuations in the mass flow rate of solid particles at the bottom of the setup. It was found that the velocity at the tip of the flue gas jet escaping from the burner nozzle, as well as the pressure at the nozzle section, have a similar form of oscillation. The authors substantiated the hypothesis about the determining influence of the instability of the jet movement of flue gases on the oscillatory behavior of the entire hydrodynamic system.
Improving methods for calculating the equivalent pressure of jet fans in large-section mine workings
Authors: Semin Mikhail A. , Maltsev Stanislav V. , Rodionov Vladimir A.
Published: July 2024

Relevance. The need to improve methods for calculating the operating parameters of jet fans in mine workings. The use of jet fans operating without air stopping is a promising option for increasing the efficiency of ventilation of large-section mine working systems. Operational analysis of the effectiveness of the selected parameters of jet fans and mixing chambers is possible only if there are sufficiently universal and accurate methods for calculating equivalent characteristics. While the approaches existing today have, as a rule, only one of the above properties. Aim. To determine the patterns of changes in the aerodynamic parameters of the air flow as it moves through a mine working with the jet fan operating without air stopping. Objects. Air flows generated in a large-section mine working as a result of the operation of the jet fan with a mixing chamber. Methods. Three-dimensional numerical simulation of steady-state turbulent air flow in a mine working, comparative analysis of calculation results for different locations of the jet fan, comparative analysis of numerically calculated equivalent characteristics of the jet fan with an analytical formula. Results. The authors have determined the patterns of changes in mechanical energy and static pressure of the air flow as it moves along the mine working. Multiparameter numerical simulation for various airflow rates at the entrance to the mine working made it possible to obtain equivalent pressure characteristics of the VM-8 jet fan with a mixing chamber, which can be used in one-dimensional calculations of the steady-state distribution of flow rates in the mine ventilation networks. A comparative analysis of simulation data with a known analytical dependence of the pressure drop made it possible to determine the directions for further improvement of analytical methods for describing air flow in mine workings with jet fans equipped with mixing chambers.
System for monitoring building heat consumption
Authors: Kolosov Mikhail V. , Lipovka Alexey Yu. , Lipovka Yuri L.
Published: July 2024

Relevance. Energy consumption and efficient use of district heating networks affect the environment, society and the economy. Solutions are needed that can significantly reduce specific thermal energy losses. Using a technically and economically feasible way to assess energy efficiency allows these decisions to be made. Currently, assessing the energy efficiency of buildings raises significant questions among specialists. There is not much modern specialized literature in this area. The problem of energy efficiency requires more rigorous attention to urban planning issues. Thus, refined methods for assessing the energy efficiency of buildings make it possible to simultaneously save capital investments and ensure efficient consumption of thermal energy. Aim. To develop a system for assessing the real heat consumption of buildings to ensure optimization of dispatching of centralized heat supply systems in real time. Methods. Computer modeling of the state of heat consumption of buildings with various characteristics and schemes for their connection to centralized heat supply networks; methods of geographic information analysis. Results. The authors have proposed the system for monitoring the heat consumption of buildings. This system allows assessing the energy efficiency of buildings through the maximum use of computer and software technologies. It is shown that the calculated heat flows of buildings used to predict savings when modernizing buildings do not always correspond to the actual heat loads, which can lead to an incorrect assessment of investment projects. The authors obtained graphical dependences of the quantities influencing specific heat losses on various primary independent factors. Conclusions. The constructed system for monitoring the heat consumption of buildings allows, together with the use of geoinformation analysis methods, obtaining a fairly complete picture of the state of heat consumption for city areas and an assessment of the energy characteristics of buildings.
Formation of nanosized copper silicides in a high-speed electric discharge plasma jet
Authors: Nikitin Dmitry S. , Nassyrbayev Artur R. , Shanenkov Ivan I. , Vympina Yuliya N. , Sivkov Alexander A. , Orlova Evgenia G.
Published: July 2024

Relevance. The search for suitable materials for creating a new generation of anodes in lithium-ion batteries that have not only high capacity, but also high electrical conductivity. For this purpose, the attempts have been made to use silicon Si, which has a high specific capacitance, instead of graphite C, but this material does not have high electrical conductivity. Copper silicides, in addition to high specific capacity, have high electrical conductivity values, since they do not react with lithium during operation, and therefore can be used to solve problems in the development of the above-mentioned lithium-ion anodes. Aim. To obtain dispersed materials in a high-speed jet of electric discharge plasma in the Cu-Si-C system. Objects. Dispersed materials obtained in the Cu-Si-C system. Methods. Plasma dynamic synthesis, X-ray diffractometry (X-ray phase analysis), scanning electron microscopy, transmission electron microscopy. Results. The authors have carried out the experimental studies to obtain dispersed materials of the Cu-Si-C system in a high-speed electric-discharge plasma jet and studied the microstructure and composition of the synthesized materials. It was revealed that the product consists of nanodispersed particles, which is confirmed by the results of scanning and electron microscopy. According to the results of X-ray diffractometry, crystalline phases of copper of the cubic system and copper silicides Cu3Si and Cu7Si of the hexagonal system are identified in the composition of the synthesized material.
Physical and mechanical properties of ceramics based on ZrN-ZrO2 obtained by spark plasma sintering method
Authors: Kuzmenko Egor D. , Matrenin Sergey V. , Nassyrbayev Artur R.
Published: July 2024

Relevance. Increasing the service life of mining tools is an important task in the development of geology associated with the investigation of new ceramic materials for functional purposes. The ability to reduce wear and thermal and chemical effects of rocks on the working elements of mining equipment determines the vector of development of the use of super-hard, high-strength and refractory ceramics. At the same time, the task is set to increase the fracture toughness of the materials used to solve the problem of maintaining the operability of equipment under conditions of critical deformations. To accomplish this task, it is necessary to study the patterns of consolidation of ceramic materials and search for the optimal combination of consolidation parameters to achieve improved physical and mechanical properties. Aim. To develop a method for producing high-density durable ceramics based on commercially available zirconium nitride powders using spark plasma sintering under vacuum conditions, to study the phase composition and physical and mechanical properties of the resulting samples. Methods. X-ray phase analysis of the studied samples, nanoindentation, microscopic analysis. Results and conclusion. The authors have studied the physical and mechanical properties of zirconium nitride consolidated by spark plasma sintering at 2000℃, a pressure of 30–60 MPa and a holding time at a given temperature of 5–10 minutes. Qualitative and quantitative X-ray phase analysis was carried out, within which the content of the main phase of zirconium nitride and zirconium dioxide phase was determined. It was found that an increase in the pressure applied during consolidation and holding time contributes to better compaction and a decrease in the porosity of the samples from 8.52 to 2.72%. It was found that with a decrease in porosity, the elastic modulus increased in the range from 320 to 378 GPa, and the hardness from 7.3 to 10.4 GPa. At the same time, by extrapolating the data, it was established that non-porous zirconium nitride samples will have an elastic modulus of 394 GPa and a Martens hardness of 11.56 GPa. For the samples under study, critical stress intensity factors were determined. It was established that at a porosity of less than 5%, the critical stress intensity factor of zirconium nitride consolidated by spark plasma sintering has values of at least 4 MPa m1/2.
Effect of coal suspension concentration and gas-air medium temperature on liquid droplets collisions
Authors: Islamova Anastasia G. , Tkachenko Pavel P. , Shulyaev Stanislav A.
Published: July 2024

Relevance. Understanding the mechanisms of liquid droplets interaction with each other is important for many industrial and technical applications related to solving a range of problems like slag removal in a high-temperature environment, obtaining components of the desired fraction in the food industry, etc. Aim. Establishment of the main patterns of suspension droplets interaction in a gas-air environment with temperature variation. Methods. Using shadow high-speed video recording, the main patterns of the binary collision of suspensions droplets were determined. The paper introduces the results of experimental studies of the characteristics of collisions of droplets of coal-water suspensions in a gas-air environment with a temperature of 90–120°C. Parameters of the generated droplets: radius 1.0–2.2 mm, velocity 0.5–2.0 m/s. Results and conclusions. The authors have determined the modes of collision of droplets of suspensions (coagulation and separation) and the main characteristics of secondary fragments and constructed the maps of the modes of interaction of drops of suspensions with each other when varying the concentration of solid particles in the suspension, the temperature of the gas-air environment and the time the target drop spent in a gas-air environment with an elevated temperature. The conditions were established for the coagulation of droplets, as well as their intensive secondary grinding to intensify their drying, ignition and combustion in boiler furnaces. It was established that an increase in the temperature of the gas-air environment leads to a significant change in the size and properties of droplets, as well as to the occurrence of oscillatory phenomena in the system. It is substantiated that collision of droplets of suspensions in a gas-air environment with elevated temperature is complex and multi-parametric. Its characteristics depend on a combination of factors (surface tension and liquid viscosity, size and shape of droplets, speed of their movement, density and viscosity of gas-air environment). The authors obtained mathematical expressions to describe the boundaries of the modes of the studied processes and schemes for using the results obtained in order to increase the efficiency of the corresponding technological processes.
Impact of woody biomass in the composition of coal-water suspensions on their transportation and combustion
Authors: Malyshev Dmitriy Yu. , Kostoreva Zhanna A. , Tamashevich Maxim S.
Published: July 2024

Relevance. A promising fuel from an environmental point of view is coal-water suspensions. Multiple studies have shown that when they are burned, emissions of anthropogenic gases into the Earth's atmosphere are significantly reduced compared to emissions from coal burning. But the large-scale introduction of coal-water suspensions into the overall balance of energy production is difficult due to a significant delay in their ignition, which can reach several tens of seconds at relatively low oxidizer temperatures (Tg≤1073 K). One of the possible ways to solve this problem is the use of new technologies for preparation for combustion, for example, the use of additional microwave heating of fuel and the introduction of special additives into the composition of coal-water suspensions, which accelerate their ignition. The introduction of such additives into the fuel composition can lead to a significant change in the rheological characteristics. Aim. To determine the degree of impact of the concentration and type of wood additive in the composition of the coal-water suspension on the rheological characteristics of droplets of coal-water fuel, as well as the possibility of reducing the duration of thermal preparation of the latter when exposed to microwave heating. Object. Water-coal suspension based on long-flame thermal coal and on long-flame thermal coal with the addition of sawdust and pine needles (Bio-water-coal suspension). Methods. Experimental studies to determine the time characteristics of water-coal suspension ignition were carried out using a high-speed video camera FASTCAM. Fuel combustion was carried out in a flow-through combustion chamber equipped with magnetrons for additional microwave heating of the fuel. Dynamic viscosity was determined using a Brookfield RVDV-II + Pro viscometer. Results. It has been established that the addition of microwave heating can significantly (up to 15%) reduce the ignition delay of water-coal suspension and Bio-water-coal suspension at relatively low oxidizer temperatures (673 K). Experimental studies shown that the type of biomass affects the time characteristics of fuel ignition at ambient temperatures up to 753 K; with a further increase in the temperature of the oxidizer, the type of additive does not have a significant effect. It is shown that when studying the rheological characteristics of the water-coal suspension, the dynamic viscosity of Bio-water-coal suspension does not go beyond the characteristic value of 1200 Pa s at a shear rate of 100 rpm when no more than 2% of pine sawdust and no more than 6% of pine needles are introduced into the water-coal suspension.
Modes of occurrence of tungsten in coals: a review
Authors: Arbuzov Sergey I. , Toropov Andrey S. , Ilenok Sergey S. , Ivanov Vladimir P. , Kholodov Aleksei S. , Zarubina Natalia V. , Ivanov Vladimir V.
Published: July 2024

Relevance. The necessity to know the conditions and forms of W concentration in coals for solving a number of scientific and engineering problems at complex development of coal deposits. Aim. Complex estimation of W modes of occurrence in coal for development of measures for rational ecologically safe use of coal. Methods. Correlation analysis, scanning electron microscopy, infrared spectroscopy, coal group analysis, inductively coupled plasma mass spectrometry, instrumental neutron activation analysis. Results and conclusions. The modes of occurrence of W in coal were studied by a complex of methods. In the majority of W-enriched coal deposits, a negative significant correlation of its content in coal and coal ash with ash yield was found, indicating its association with organic matter. Using the method of coal group composition analysis, it was found that the main carrier and concentrator of W in the studied lignite deposits is organic matter. The contribution of the mineral phase in general in W-rich coals and in coals with its normal content does not exceed 20%, usually less than 5%. These conclusions are also confirmed by infrared spectroscopy data, according to which no more than 15% of the metal in the samples studied is associated with mineral phases. The association of W with high molecular humic acids predominates. In anomalously W-enriched lignites, the humic acid phase represents 76 to 88% of the gross metal content. The role of bitumen and low-molecular-weight humic acids in the balance of W is marginal at their different levels in the coals. Mineral phases of W are not characteristic of coal. Nano-microinclusions of scheelite, wolframite, hubnerite and ferberite were recorded as isolated occurrences. The main mineral phases are associated with Fe and Mn hydroxides, in which W is presented as a trace element in the amount of 1–5% together with other elements (Ge, As, etc.). In more metamorphosed bituminous and anthracite coals, authigenic mineral formations were found, represented by tungstite, phyllotungstite, native W and complex Fe-Mn-Ca-W-O mineral phases.