bluuebunny/crossref_metadata_2025 huggingface dataset:
AVANCES EN LA IDENTIFICACION DE MINERALES CONTAMINANTES EN SUELOS DE LA RESERVA NACIONAL DE JUNIN
Authors: Fabián S. Julio , Solórzano P. Edgardo , Noreña D. Alberto
Published: May 2021

Las muestras que se estudian están localizadas en la Reserva Naciomil de Junín ubicada en las provincias y regiones de Junín y Paseo, en la sierra central del Perú, entre los 10°54" y 1F08" Latitud Sur y los 76°00" y 76°15'' Latitud Oeste a 4 081.60 m.s.n.m. El gran valor ecológico que tiene por la gran biodiversidad en especies que alberga en sus tres principales comunidades ecológicas (terrestre, acuática y ornitológica); además de servir de regulador hídrico para la central hidroeléctrica del Mantaro hacen que un estudio de suelos de este lugar sea muy importante. Las técnicas analíticas utilizadas para la caracterización mineralógica, fueron la difracción de rayos X, fluorescencia de rayos X y espectroscopia Mossbauer de Transmisión como una técnica de análisis complementaria. También se realizó procedimientos físicos y químicos para medir la capacidad de intercambio catiónico, pH, determinación de porcentaje de Materia Orgánica, porcentaje de salinidad y conductividad eléctrica. Para eliminar la alta concentración de hierro en los suelos fue usado el tratamiento DCB (diotinito citrato bicarbonato) en algunos casos. Los difractogramas de rayos X de las muestras tratadas por DCB dan la presencia de diferentes tipos de arcillas, óxidos de hierro y minerales de difícil aparición en un suelo común. Los análisis hechos con fluorescencia de rayos X indicaron la presencia de rubidio, tungsteno, calcio, hierro, níquel, cobre, zinc, oro y zirconio. Los minerales identificados por espectroscopía Mossbauer a temperatura de ambiente mostraron la presencia en mayor proporción de hierro paramagnético, pero también hay hierro magnético. El hierro paramagnético indica dos sitios y el hierro magnético al parecer muestra una distribución de sitios.
Estimación de Lluvias Mensuales Durante el Evento el Niño Débil a Moderado 2002
Authors: Fashé Raymundo O. , Rojas Acuña J.
Published: May 2021

El objetivo central de este artículo es la estimación de las lluvias mensuales sobre Perú durante EL NIÑO débil a moderado del año 2002. Para esto se utilizan imágenes del satélite GOES-8 y la técnica convectiva estratiforme. Se presentan un análisis de los resultados de la comparación entre los estimados GOES-8 y valores de lluvia mensual mediada en pluviómetros. Se observa que la estimación de la tasa de lluvia mensual sobre la selva peruana ofrecen las mejores correlaciones. Sin embargo es la sierra peruana la que presenta los mínimos errores de sesgo. Se desarrolla una explicación a estos resultados haci ndo un análisis de estimaciones de tasa de lluvia que diversos autores realizan so re otras latitudes.
DETERMINACIÓN EXPERIMENTAL DE LA TASA DE DOSIS DE NEUTRONES EN LOS AMBIENTES DEL REACTOR DE INVESTIGACIÓN RP–0 UTILIZANDO DETECTORES POLÍMEROS CR–39
Authors: Aparicio O. C. , Avila L. J. , Zuñiga G. A.
Published: May 2021

Se ha medido la tasa de dosis neutrónica en diferentes posiciones dentro y fuera del recinto del Reactor de Potencia Cero (RP–0) del Instituto Peruano de Energía nuclear (IPEN); para ello se ha utilizado un método basado en la detección de huellas nucleares dejadas por partículas cargadas producidas por una reacción nuclear entre los neutrones y el material que se use como detector. El material utilizado fue el polímero CR–39, por ser insensible a la radiación gamma; el principio de detección de neutrones es la reacción (n,p) con el nitrógeno contenido en el aire, las huellas se hacen visibles luego de someter el polímero a un revelado químico. La calibración del CR-39, se llevó a cabo en la columna térmica por tener ésta el 95,5% de flujo térmico, que es lo que se desea detectar. Como resultado de la calibración del polímero, en la columna térmica, se obtuvo el factor de calibración que permitió obtener el valor de la dosis neutrónica ((1,87 ± 0,19)x10-2 cm2 mSv), y conocido el tiempo de irradiación se determinó el valor de la tasa de dosis neutrónica. Los valores de tasas de dosis neutrónica más representativos a 7 w de operación que se obtuvieron son: 7,67 mSv/h (± 16%) en el contorno del tanque del reactor, 8,29 mSv/h (± 12%) en el puente de maniobras sobre el tanque del reactor, 1,26 mSv/h (± 12%) en consola de operación y 0,49 mSv/h (± 16%) en el laboratorio de física. Estos valores son algo elevados e incrementan la dosis total que debería recibirse por año (20 mSv), por lo que no se recomienda trabajar a esta potencia de operación. Palabras claves: CR-39, dosimetría de neutrones, huellas nucleares.
CALCULO AB-INITIO DE LA ESTRUCTURA ELECTRÓNICA DEL TOPACIO Al2SiO4(F,OH)2
Authors: Flores Luis , Gómez Javier , Nowak Hans , Bustamante Domínguez Angel
Published: May 2021

En este trabajo se realizó el cálculo ab-initio de la estructura de bandas y DOS del Topacio con Flúor (F) e Hidróxido (OH) en el estado fundamental, con el modelo TB-LMTO-ASA. La celda convencional de estos 2 cristales no presentan las mismas dimensiones, debido al reemplazo de iones F por moléculas OH. Los estados energéticos se verán afectados por esta nueva estructura con OH, haciendo variar el comportamiento de las bandas, de la DOS y por lo tanto variando las propiedades ópticas del cristal.
LA GRAVITACION COMO UN MODELO DE CUERDA Y SU CUANTIZACION EN EL ESPACIO DE MINKOWSKI
Authors: Villegas Silva Fulgencio
Published: May 2021

Se considera las ecuaciones de campo gravitacional de Einstein, identificándolas con las funciones que describen la inmersión del espacio-tiempo en un espacio plano encontrando así un modelo de teoría de campo. Se hace uso del Lagrangiano de Hilbert de tal manera que los campos dinámicos midan la curvatura del espacio-tiempo donde el tensor energía-momento es proporcional al tensor de Einstein.
Some Results on a Generalized Version of Congruent Numbers
Authors: Casinillo Leomarich F. , Casinillo Emily L.
Published: May 2021

AbstractThis paper aims to construct a new formula that generates a generalized version of congruent numbers based on a generalized version of Pythagorean triples. Here, an elliptic curve equation is constructed from the derived generalized version of Pythagorean triples and congruent numbers and gives some new results.Keywords: Pythagorean triple, congruent number, elliptic curve equation. AbstrakArtikel ini bertujuan untuk mengkonstruksi formula baru yang membangun versi yang lebih umum dari bilangan-bilangan kongruen berdasarkan versi triple Pythagoras yang diperumum. Di sini, akan dikonstruksi suatu persamaan kurva eliptik dari triple Pythagoras dan bilangan-bilangan kongruen dalam versi yang diperumum untuk menghasilkan hasil-hasil yang baru.Kata kunci: triple Phytagoras, bilangan kongruen, persamaan kurva eliptik.2010 Mathematics subject classification: 11A07, 11A41, 11D45, 11G07.
Space-Time and Motion to Advection-Diffusion Equation
Authors: Ghani Mohammad
Published: May 2021

AbstractWe are concerned with the study the differential equation problem of space-time and motion for the case of advection-diffusion equation. We derive the advection-diffusion equation from the conservation of mass, where this can be represented by the substance flow in and flow out through the medium. In this case, the concentration of substance and rate of flow of substance in a medium are smooth functions which is useful to generate advection-diffusion equation. A special case of the advection-diffusion equation and numerical results are also given in this paper. We use explicit and implicit finite differences method for numerical results implemented in MATLAB.Keywords: advection-diffusion; space-time; motion; finite difference method. AbstrakKami tertarik untuk mempelajari masalah persamaan diferensial ruang-waktu, dan gerak untuk kasus persamaan adveksi-difusi. Kita menurunkan persamaan adveksi-difusi dari kekekalan massa, di mana hal ini dapat diwakili oleh aliran zat yang masuk dan keluar melalui media. Dalam hal ini konsentrasi zat dan laju aliran zat dalam suatu medium merupakan fungsi halus yang berguna untuk menghasilkan persamaan adveksi-difusi. Sebuah kasus khusus persamaan adveksi-difusi dan hasil numerik juga diberikan dalam makalah ini. Kami menggunakan metode beda hingga explisit dan implisit untuk hasil numerik yang diimplementasikan dalam MATLAB.Kata kunci: adveksi-difusi; ruang-waktu; gerak; metode beda hingga.
First record of Macrobrachium grandimanus (Crustacea, Decapoda, Palaemonidae) from Guam, Micronesia
Authors: Fuke Yusuke , Sasazuka Makoto
Published: May 2021

The Hawaiian river shrimp Macrobrachium grandimanus (Randall, 1840) is an amphidromous brackish water prawn that inhabits the Hawaiian Islands (type locality), Ryukyu Islands, Melanesia (Fiji, New Caledonia), and Polynesia (Tonga). Here, we report a new record of this species from Guam, Micronesia. Two genetically and morphologically differentiated lineages of this species are known: the Hawaiian and the Ryukyu lineages. Morphological and mitochondrial DNA analyses revealed that the Guam population is closely related to the Ryukyu lineage.
The Impact of Organizational Justice, Self-Efficacy and Teachers Performance: The Mediating Role of Internal Motivation
Authors: Sopiah Sopiah , Mamang Sangadji Etta , Shandy Narmaditya Bagus
Published: May 2021

This study examines the impact of organizational justice and self-efficacy on teachers’ performance in Indonesia and the role of internal motivation. Using path analysis, the findings indicate that both organizational justice and self-efficacy can affect teacher performance and correlate with internal motivation. Additionally, internal motivation plays a role as a partial mediating relationship between organizational justice and teacher performance, as well as mediating self-efficacy and teacher’s performance.
Effect of loading rate on crystallization of metallic glass supercooled liquids
Authors: Davoodi E. , Hasan M. , Rana S. , Kumar G.
Published: May 2021

Metallic glasses exhibit unique thermoplastic processing capability, which is enabled by their metastable supercooled liquid state below the crystallization temperature. The thermoplastic processing critically depends on the crystallization time (processing time window), temperature
(viscosity), applied load, and strain-rate. Among these parameters, the effects of crystallization time and processing temperature have been extensively studied. However, the effects of load and loading rate have not been thoroughly investigated. In this work, we performed a systematic study
of load on the supercooled liquid state of three metallic glass formers: Pt-based, Zr-based, and Pd-based. The results show that the load-response of a metallic glass supercooled liquids is strongly composition dependent. The onset temperature of crystallization decreases with increasing load
in Pt-based metallic glass whereas for Zr-based and Pd-based metallic glasses the onset temperature remains unchanged. The crystallization peak time is reduced for all three metallic glasses after thermoplastic forming. The results are discussed in terms of nucleation and growth of crystallites
in metallic glasses.
Il cambiamento radicale delle politiche migratorie: dal lasciar vivere al lasciare morire (dalla biopolitica a sempre più tanatopolitica)
Authors: Palidda Salvatore
Published: May 2021

Riassunto Il testo descrive gli aspetti salienti dell’attuale congiuntura mondiale. Attraverso una sintetica analisi del processo che ha portato al trionfo del liberismo globalizzato, si mostra come a cominciare dal 1990 la guerra alle migrazioni si inscriva in una vera e propria tanatopolitica (il lasciar morire). Infatti, i dominanti designano le migrazioni come il nemico del XXI° secolo perché temono che l’aumento della popolazione mondiale sia incontrollabile e che si sovrapponga ai cambiamenti climatici provocando - secondo loro - destabilizzanti invasioni di migranti nei paesi ricchi. In realtà temono che si imponga la necessità di una redistribuzione egualitaria della ricchezza mondiale che potrebbe permettere la sopravvivenza decente anche di oltre 10 miliardi di umani a condizione anche di eliminare tutte le fonti di distruzione del pianeta e innanzitutto l’estrattivismo di carbone, petroli, gas, uranio e terre rare.
Atrapados en busca de asilo. Entre la externalización fronteriza y la contención sanitaria
Authors: Iturralde Lorena Mena , Piñeiro Rodolfo Cruz
Published: May 2021

Resumen En la región México-Estados Unidos las políticas para controlar y disuadir los desplazamientos migratorios irregulares han alcanzado también a los buscadores de asilo quienes en los últimos años viven un limbo de inmovilidad y desprotección, ahora agravado por la pandemia de la COVID-19. En este artículo se analizan las implicaciones del programa MPP, del sistema de refugio en México y de la crisis sanitaria sobre las personas con necesidades de protección internacional. Los resultados muestran cómo las restricciones y ralentización de los procesos de asilo y refugio han generado distintas condiciones de atrapamiento, mientras la pandemia acentuó el enfoque de securitización migratoria en torno a un riesgo que debe ser contenido.
Symbolic Impact of Research
Authors: Oliveira Josiane Silva de , Davel Eduardo Paes Barreto
Published: May 2021

Abstract Most understandings obtained from the numerous debates about the impact of scientific research on society are concentrated on the economic, social, cultural and technological dimensions, thus urging for a deeper understanding of the impact on its cultural and, particularly, symbolic dimensions. Every research result bears a symbolic weight that will impact organizations and society. Thus, researchers must reflect on how to produce results while aware and sensitive of the symbolic impact they may cause. Symbolic impacts are decisive for understanding the subtle, deep and structuring value that research results have in developing and transforming society and organizations.
Ethnographing Historical Archives: Possible Ways to Research in Organization Studies
Authors: Lopes Luma Louise Sousa , Ipiranga Ana Silvia Rocha
Published: May 2021

Abstract Our objective in this article is to discuss the contributions of archival ethnography as a method of historical research in management. We indicate that, while historical research is already relevant in the management research area, there is still a dilemma regarding the possibility of how to access the past and conduct research of this nature. In this context, ethnography associated with historical archives emerges as a legitimate source, loaded with voices and silences to be unveiled in the processes of reflection on time in the context of organizations. Thus, we discuss the characteristics and possibilities of the method of an archival ethnography, considering its multi-situated character in the proposed research strategy. Thus, we hope to foster the discussion about ethnographic immersion in historical archives and how this method can contribute to the several research areas in management and more specifically in Organization Studies.
De Kant a Popper: Razão e Racionalismo Crítico nos Estudos Organizacionais
Authors: Couto Felipe Fróes , Saraiva Luiz Alex Silva , Carrieri Alexandre de Pádua
Published: May 2021

Abstract The objective of this essay is to revisit the theoretical construction of Critical Rationalism, starting from the philosophy of Kantian reason contained in the works Critique of pure reason and Critique of practical reason to discuss their respective influences over the work of Karl Popper. We aim, with this exercise, to shed light on the critical-rationalist approach in Organization Studies. Our argument is that Kantian thought has been conducive, on the one hand, to a negative philosophy that considers idealism prior notions and a priori knowledge fundamental to the creative conception of knowledge and, on the other hand, to a hypothetical-deductive science that seeks to bring us closer to truth through criticism. The basis of critical rationalism lies in the search for reason and transcendental truth. This is a call not only for the production of theories, but for dedication to test their validity – a problem that has not received much attention from researchers in the field of organization studies.
Inequalities and Resistances in The Organization of Marginalized Festive Practices
Authors: Silva Nathália Brunet Procópio da , Fantinel Letícia Dias
Published: May 2021

Abstract This article is based on the understanding of festivals as organizations and events that are multiform and establish mediations with society (Amaral, 1998a; Davel, 2016). Based on a multi-political perspective, our objective was to reflect on the social production of inequalities and forms of resistance in the organization of the congo capixaba festival, in the state of Espírito Santo. Our theoretical reflections were grounded in Certeau’s (Certeau, 1985, 2008, 2012; Certeau, Giard, & Mayol, 2003), Hall’s (2003, 2011) and Sansone’s (2004) discussions and reflections regarding contemporary black culture. Our empirical field of investigation was the Carnaval de Congo de Máscaras [Congo Masquerade Carnival], in Roda D’água, where we employed the ethnographic method as a data production and interpretation strategy. Our findings indicate the existence of “non-places” as products of historically produced conditions of social marginality, as well as an ethnic-racial invisibility reinforced in the festival’s organizational context. These non-places operate in the religious, touristic, and cultural macropolitical fields. On the other hand, we highlight how the subjects of such conditions deal with them by employing certain micropolitical tactics, which figure prominently in their everyday lives, and articulate themselves around a sense of tradition and belonging.
Clinical validation of an in-house quantitative real time PCR assay for cytomegalovirus infection using the 1st WHO International Standard in kidney transplant patients
Authors: Caurio Cassia F.B. , Allende Odelta S. , Kist Roger , Santos Kênya L. , Vasconcellos Izadora C.S. , Rozales Franciéli P. , Lana Daiane F. Dalla , Praetzel Bruno M. , Alegretti Ana Paula , Pasqualotto Alessandro C.
Published: May 2021

Abstract Introduction: Cytomegalovirus (CMV) is one of the most common agents of infection in solid organ transplant patients, with significant morbidity and mortality. Objective: This study aimed to establish a threshold for initiation of preemptive treatment. In addition, the study compared the performance of antigenemia with qPCR results. Study design: This was a prospective cohort study conducted in 2017 in a single kidney transplant center in Brazil. Clinical validation was performed by comparing in-house qPCR results, against standard of care at that time (Pp65 CMV Antigenemia). ROC curve analysis was performed to determine the ideal threshold for initiation of preemptive therapy based on the qPCR test results. Results: Two hundred and thirty two samples from 30 patients were tested with both antigenemia and qPCR, from which 163 (70.26%) were concordant (Kappa coefficient: 0.435, p<0.001; Spearman correlation: 0.663). PCR allowed for early diagnoses. The median number of days for the first positive result was 50 (range, 24-105) for antigenemia and 42 (range, 24-74) for qPCR (p<0.001). ROC curve analysis revealed that at a threshold of 3,430 IU/mL (Log 3.54), qPCR had a sensitivity of 97.06% and a specificity of 74.24% (AUC 0.92617 ± 0.0185, p<0.001), in the prediction of 10 cells/105 leukocytes by antigenemia and physician's decision to treat. Conclusions: CMV Pp65 antigenemia and CMV qPCR showed fair agreement and a moderate correlation in this study. The in-house qPCR was revealed to be an accurate method to determine CMV DNAemia in kidney transplant patients, resulting in positive results weeks before antigenemia.
Os Kollegnachschriften de Nietzsche. Considerações sobre uma lacuna das obras completas
Authors: Nasser Eduardo
Published: May 2021

Resumo: Não obstante as reconhecidas virtudes da edição crítica - Kritische Gesamtausgabe (KGW) -, há o entendimento de que as duas primeiras seções dessa edição, que abrangem os escritos de juventude e filológicos, possuem lacunas. Uma dessas lacunas, contida na seção I, decorre da problemática decisão de não incorporar, em sua totalidade, os registros de aulas realizados por Nietzsche no período universitário, os Kollegnachschriften, valiosos tanto para estudos genéticos e de contextualização, como também para estudos de fontes. Muito embora o surgimento da Digitale Faksimile Gesamtausgabe (DFGA) tenha dado início a um reparo dessa falha ao publicar todos os cadernos universitários de Nietzsche em formato fac-símile, os problemas de acesso a esses documentos não foram ainda completamente superados.
A interpretação nietzschiana de Pierre Hadot
Authors: Busellato Stefano
Published: May 2021

Resumo: Com a própria concepção de “filosofia como modo de viver”, Pierre Hadot inaugurou uma das mudanças de paradigmas exegéticos mais significativas do período recente. Elaborada a partir de autores antigos, as características e as razões interpretativas desse novo paradigma tornam a proposta de Hadot capaz de abarcar outras épocas e autores diversos. Dentre eles, um papel de destaque é confiado a Friedrich Nietzsche, sobre o qual Hadot detém-se com regularidade e insistência em muitas de suas obras. O presente artigo oferece uma reconstrução do percurso teórico-filosófico que levou o estudioso francês a elaborar a própria concepção interpretativa e pretende mostrar a leitura que, no interior dele, faz-se das especificidades filosóficas nietzschianas. Sua concepção se mostra como uma abordagem diferenciada das páginas de Nietzsche e apresenta elementos de grande originalidade com uma visão que convida a ser refletida e aprofundada.
Analysis of hybrid joints of green composites under tensile and compressive loadings
Authors: Choudhury Mridusmita Roy , Debnath Kishore
Published: May 2021

Adhesive bonding and mechanical fastening techniques are mostly applied for the joining of polymer composites. However, in recent times, the hybrid joining (bonded/bolted) technique is emerging, as it prevents premature failure of composite joints. An experimental investigation was carried out in this study to analyze the hybrid joining behavior of green composites (bamboo/poly(lactic acid) (PLA)) under tensile and compressive loadings. The hybrid joints were developed by combining bolted and bonded joints. The hole in the specimen prerequisite for the bolted joint was obtained by traditional drilling performed at a constant spindle speed of 2000 revolutions per min and an axial feed of 45 mm/min using a multifaceted solid carbide drill bit. A bolt fastening torque of 20 N m was applied to facilitate the mechanical joining. Three bonding materials – namely, (a) epoxy, (b) polyurethane and (c) parent polymer (PLA) – were used to obtain the bonded joint. The important factors of the hybrid joint, such as (a) overlapping length, (b) width of the specimen and (c) bonding material, were considered, and their effect on both tensile and compressive failure loads was evaluated. The significance of the parameters of the hybrid joint was evaluated through statistical modeling.
Plasma-assisted fabrication of hydrophobic siloxane based sol–gel-coated coir fibres
Authors: Praveen K M , Primc Gregor , Simončič Barbara , Gorjanc Marija , Pillin Isabelle , Seantier Bastien , Kervoelen Antoine , Vesel Alenka , Kalarikkal Nandakumar , Mozetič Miran , Grohens Yves , Thomas Sabu
Published: May 2021

This work focuses on a novel technique based on the spray–dry–cure method to establish a hydrophobic sol–gel coating on a lignocellulosic coir fibre surface. The fibres were first activated with oxygen plasma to ensure spreading of the droplets and thus coating uniformity. The efficiency of this method was highlighted by the high content of fluorine (52.1%) coming from the sol–gel-coated coir fibre revealed by X-ray photoelectron spectroscopy analysis. Scanning electron microscopy showed that the sol–gel coating was uniformly deposited. This had a drastic effect on the coir fibre surface and mechanical properties. The contact angle measurements show that the coir fibre surface becomes extremely hydrophobic after application of the sol–gel coating. The work of adhesion changed from 121.7 to 46 mJ/m2. Besides this drastic change into a hydrophobic surface, this study also highlighted the higher average breaking force (from 6.4 to 9.8 N), breaking strength (from 108.1 to 148.3 MPa), modulus (from 1819.1 to 2004.6 MPa) and elongation at break (from 45.9 to 60.4%) when coir fibres are plasma treated and sol–gel coated. This work shows that by using this sol–gel coating treatment, the authors have been able to overcome the major drawbacks of coir fibres, such as moisture absorbency, for their use in industry.
Análisis del fracaso de las MiPyME franquiciantes en México. Un crecimiento cuestionable del sector
Authors: Cortes Castillo Maria del Rosario , Saavedra Garcia María Luisa , Palacios Duarte Pablo Daniel
Published: May 2021

El objetivo de esta investigación consiste en determinar la tasa del fracaso de las MiPyME franquiciantes mexicanas durante el período 2005-2014. Se realizó una investigación exploratoria descriptiva bajo un diseño de investigación longitudinal, que abarco 10 años, ex post facto evolutivo; se recolectaron datos de fuentes secundarias y se estudió la evolución de 7037 Mipymes franquiciantes mexicanas de los sectores comercio y servicios. Entre los principales hallazgos se encontró una caída vertiginosa de las Mipymes franquiciantes mexicanas, las cuales fracasaron en su intento por adoptar este modelo en un 11 %; mientras que un porcentaje superior (13 %) abandonó el modelo de franquicias. En conclusión, estos resultados ponen en duda los códigos establecidos de que una franquicia reduce los riesgos de fracaso y facilita la expansión y el crecimiento de una MiPyME.
Evaluation of elasticity of the pancreas by Acoustic Radiation Force Impulse (ARFI) in acute pancreatitis patients: A systematic review and meta-analysis (protocol) v1
Authors: Rifu Kazuma , Watanabe Jun , Sasanuma Hideki , Taniguchi Nobuyuki
Published: May 2021

Acute pancreatitis (AP) is characterized by inflammation of the pancreas(1). The morbidity of AP is reported about 5-80/100000 people/year (2). An increase in the incidence of AP has been also reported (3-9). The mortality rate has been reported to be 1.7-8.4% (10, 11), and AP still remains a life-threatening disease. Clinical symptoms and elevated levels of pancreatic enzymes constitute the main diagnostic features of this condition.(12, 13) Early diagnosis and treatment are important, and reliable imaging techniques are required for a diagnosis of acute pancreatitis. Acoustic radiation force impulse (ARFI) elastography is a promising ultrasound-based imaging modality for the evaluation of tissue stiffness including in the diagnosis of AP (14). Studies using the ARFI elastography evaluated different abdominal organs(15), especially in pancreatic disease, such as AP, chronic pancreatitis, or pancreatic carcinoma, relevant higher shear wave velocities than in healthy pancreas parenchyma are described(1, 16, 17). In this study, we evaluated acoustic radiation force impulse (ARFI) elastography, Virtual Touch tissue quantification (VTQ; Siemens Medical Solutions, Mountain View, CA),to diagnose acute pancreatitis. The consistency of the pancreatic parenchyma usually becomes stiffer in acute pancreatitis as compared to the healthy pancreas, which is identifiable with Share Wave Elastography (SWE), including ARFI (18, 19). However, studies using elastographic techniques in patients with acute pancreatitis are conflicting(19).One prospective study failed to find significant differences in pancreatic shear wave velocities between patients with AP and healthy volunteers(14, 19). Three other studies showed significantly higher pancreatic shear wave velocities in patients with acute pancreatitis compared to persons with the normal pancreas(1, 18-20). The present study will aim to assess the effectiveness of ARFI elastography in the form of ARFI-VTQ imaging in characterizing and differentiating normal pancreas and acute pancreatitis.
Еstrogen receptor α (ESR1) and SRC family kinase (LYN) gene's mutations associated with ovarian cancer endocrine therapy resistance
Authors: Shestakova E. A.
Published: May 2021

Recently multiple data accumulated concerning mutations in the ESR1 gene coding estrogen receptor α (mutESR1) and in the LYN gene coding non receptor tyrosine kinase SRC family member (mutLYN) that are associated with endocrine therapy resistance and that could be considered as markers of endocrine therapy efficiency. In case of gynecologic cancers including ovarian cancer the most frequent mutESR1 are ESR1L536H/P/R/V , ESR1Y537S/N/C/H, ESR1D538G that emerge in the course of hormonotherapy especially using aromatase inhibitors. mutLYN including LYNE159K, LYND189Y, LYNK209N, LYNA370T, LYNG418R, LYNA503D are also identified. mutESR1 and mutLYN increase transcriptional activity of estrogen receptor α (ERα) coded with ESR1 gene and catalytic activity of LYN kinase inducing endocrine therapy resistance. Interdependence of ESR1 and LYN genes is revealed at the level of proteins that they code as the kinases of the SRC family including LYN activate ERα-dependent transcription due to the phosphorylation of ERα at Y537 amino-acid residue that is the most frequently mutated in tumors with endocrine therapy resistance.

 The aim of the review is revealing the clinical correlations of mutESR1 and mutLYN with the ovarian cancer endocrine therapy resistance that opens perspectives of mutESR1 and mutLYN use as new predictive markers of ovarian cancer and development of more efficient anti-tumor medicaments. In the review the information obtained from PubMed database for the last 20 years using the following key words: ESR1, LYN, mutation(s), estrogen receptor α (ERα), LYN kinase, SRC family kinases, ovarian cancer, gynecologic(al) cancer is discussed.
Neurofibromatosis type 1: results of our own study (Republic of Bashkortostan)
Authors: Mustafin R. N. , Bermisheva M. A. , Valiev R. R. , Khusnutdinova E. E.
Published: May 2021

Introduction. Neurofibromatosis type 1 (NF1) is the most common hereditary tumor syndrome (frequency of its occurrence in the world is 1 : 3000 of the population). The main clinical manifestations of the disease are multiple café-au-lait macules on the skin and neurofibromas, skeletal abnormalities and cognitive deficits. The disease is based on mutations in the oncosuppressor gene NF1. This disease is characterized by significant clinical polymorphism of manifestations, even among members of the same family. No geno-phenotypic correlations were found for NF1. Therefore, it is assumed that modifier genes are the cause of the varying expressiveness of the disease.

 Materials and methods. Clinical-epidemiological and molecular-genetic research of patients with NF1 in the Republic of Bashkortostan (RB) was carried out. Sequencing was used to search for intragenic mutations in 57 exons of the NF1 gene. Microsatellite analysis was used to detect the deletion of the entire gene.

Results. The frequency of occurrence of NF1 in RB was 1 : 10153 of the population. Analysis of the clinical manifestations of NF1 in RB patients showed a lower incidence of brain cysts in patients born in mixed marriages, which indicates the protective role of mestization. In patients with NF1 who inherited the disease from the mother, a more frequent development of skeletal anomalies and facial dysmorphism was determined. We identified 1 deletion of the entire NF1 gene in 1 patient and 14 intragenic mutations (c.205-1G>C, с.1278G>A, c.1369_1370insGGGTC, с.1570G>A, с.1973_1974delTC, c.2806A>T, с.2991-1G>C, c.3158C>G, с.3526_3528delAGA, с.3826delC, с.4514+5G>A, с.4537С>Т, c.5758_5761delTTGA, с.6792С>A) in 20 patients with NF1. We determined the random distribution of the types of mutations and did not reveal the specific features of the NF1 clinic depending on the type of mutations.

Conclusions. The protective role of crossbreeding in relation to brain cysts, as well as the predominance of skeletal anomalies in patients with NF1 inheritance from the mother, indicate the role of modifier genes in the pathogenesis of the disease. The identified mutations in the NF1 gene will allow us to perform prenatal prevention of NF1 in RB patients.
Studying of the effect of the genetic variant c.470T>C in the CHEK2 gene on increasing the risk of breast cancer in the population of the Russian Federation
Authors: Novikova E. I. , Bozhenko V. K. , Kudinova E. A. , Solodkiy V. A.
Published: May 2021

Introduction. Currently, there are conflicting data regarding the effect of the c.470T> C germline mutation in the CHEK2 gene on increasing the risk of breast cancer (BC), so it is necessary to conduct research on large samples of patients, including in the Russian population, in order to analyze the contribution of this mutation to the risk of cancer developing.

The aim of the study was to determine the frequency of occurrence of the genetic variant c.470Т>С in the CHEK2 gene in the Russian population in patients with BC and patients with benign breast diseases (BBD) to assess the possible effect of this deoxyribonucleic acid damage on the likelihood of cancer occurrence.

Materials and methods. The study included 2,787 patients with BC and 1,004 patients with BBD who underwent examination and treatment at the Russian Scientific Center of Roentgenoradiology of the Ministry of the Russian Federation from 2010 to 2018. Molecular genetic study was carried out by real-time polymerase chain reaction to determine the characteristic of the Russian population hereditary genetic variant c.470Т>С in the CHEK2 gene using a diagnostic panel that allows to determine three germline mutations: c.1100delC, c.444+1G>A and c.470Т>С in the CHEK2 gene.

Results. In patients with BC the frequency of the mutation c.470T>C in the CHEK2 gene was 3.8 %, in patients with BBD this mutation was detected in 4.7 % of cases. The frequency of the genetic variant c.470T>C in high-risk groups was: 5.1 % – for BC patients with clinical signs of hereditary disease and 4.9 % – for patients with BBD with a family history of cancer. There were no statistically significant differences between the frequency of the mutation c.470T>C in the general groups of BC patients and patients with BBD and the corresponding frequency in the high-risk groups, as well as in the groups of BC patients and patients with BBD (p >0.05).

Conclusion. The results of this study indicate the probable absence of a relationship between the presence of the mutation c.470Т>С in the CHEK2 gene and an increased risk of BC.
The effect of hypoxia on the secretome of human glioblastoma multiforme cells
Authors: Kushnir T. I. , Arnotskaya N. E. , Kudryavtsev I. A. , Mitrofanov A. A. , Bekyashev A. K. , Shevchenko V. E.
Published: May 2021

Background. Glioblastoma multiforme (GBM) develops in the hypoxic microenvironment, which plays an important role in the pathogenesis of the disease and is closely associated with tumor growth, development and poor prognosis. Hypoxia increases the resistance of tumor cells (TC) to radiation therapy and chemotherapy, promotes the appearance of an aggressive TC phenotype, leading to the disease recurrence. The molecular mechanism of hypoxic action on the secretome of GBM cells, which is involved in the formation of the tumor microenvironment, remains unclear. Also, markers of the aggressive hypoxia-associated phenotype of tumor cells have not been established.

 The purpose of research – to study the molecular mechanisms of the hypoxia-associated effect on the secretome of the U251 GBM cells.

Materials and method. High resolution proteomic mass spectrometry, cell technologies.

Results. A total of 1432 proteins were identified in the secretomes of two types of GBM cells (control and experiment). After the action of hypoxia, statistically significant changes in the expression of 390 proteins were registered. 11 proteins showed increase in expression over two orders of magnitude. The intracellular signaling pathways which are responsible for the hypoxia-associated effects on the U251 GMB cells have been identified.

Conclusions. Hypoxia significantly affected the proteomic composition of the GBM cells secretome. Five overexpressed secretome proteins, S100A6, HEY1, ZIP3, S100A4, ZEB2, have been proposed as potential markers of the hypoxiaassociated phenotype of GBM, for which participation in the pathogenesis of glioblastoma multiforme has been previously showed.
Effect of caveolin-1 knockdown on the protein composition of extracellular vesicles secreted by non-small cell lung cancer cells
Authors: Skryabin G. O. , Komelkov A. V. , Kopnin P. B. , Nikishin I. I. , Kuzmichev S. A. , Tchevkina E. M.
Published: May 2021

Background. Recent data show evidence that lipid rafts (LR) proteins could be involved in the formation of exosomes and the sorting of proteins that make up the exosomal cargo. Such data are available for flotillins, structural and functional components of flatted rafts. The presence of the main component of caveolar rafts, caveolin-1 (Cav-1), has been shown in exosomes produced by some cancer cells; however, its possible participation in the regulation of the protein composition of exosomes has not been studied previously.

Materials and methods. Knockdown of Cav-1 by transduction of a lentiviral vector expressing precursors of short hairpin ribonucleic acid to Cav-1; isolation (by ultracentrifugation) and analysis (transmission electron microscopy, nanoparticle tracking analysis) of extracellular vesicles (EVs) from non-small cell lung cancer cells (NSCLC) H1299; analysis of proteins in cells and in EVs by immunoblotting.

Results. Analysis of the effect of Cav-1 expression on the composition of EV proteins associated with exosome biogenesis revealed a decrease in the level of Alix and TSG101, an increase in the level of LR proteins and the absence of changes in the level of tetraspanin CD9.

 Conclusion. The obtained data demonstrate a Cav-1-dependent changes in the composition of EVs, indicating a change in the ratio of vesicles formed by the various molecular mechanisms.
Gelişim Öz-teorisine Göre Tasarlanan Etkinliklerin 7. Sınıf Öğrencilerinin Hücre ve Bölünmeler Ünitesini Öğrenmelerine ve Motivasyonlarına Etkisi
Authors: ORHAN Sema , AYDIN Abdullah
Published: May 2021

Bu araştırmada, 7. sınıf fen bilimleri dersi hücre ve bölünmeler ünitesine yönelik olarak gelişim öz-teorisi doğrultusunda hazırlanan etkinliklerin, öğrencilerin düşünce tarzı, hücre ve bölünmeler ünitesine ilişkin akademik başarıları ve fen öğrenmeye yönelik motivasyonlarına etkisinin belirlenmesi amaçlanmıştır. Bu amaç doğrultusunda, 2019-2020 eğitim-öğretim yılı güz yarıyılında Kastamonu il merkezindeki bir devlet ortaokulunda iki şubede öğrenim gören 54 yedinci sınıf öğrencisi ile araştırma yapılmıştır. Basit rastgele örneklem seçimi ile bu şubelerden biri deney (N=27), diğeri ise kontrol grubu (N=27) olarak belirlenmiştir. Kontrol grubundaki öğrencilere hücre ve bölünmeler ünitesi 2018 Fen Bilimleri Dersi Öğretim Programına göre anlatılırken, aynı konu deney grubundaki öğrencilere mevcut öğretim programına ilaveten gelişim öz-teorisi doğrultusunda hazırlanan etkinliklerle desteklenerek anlatılmıştır. Nicel araştırma yaklaşımı temelinde yürütülen araştırmada, ön-test son-test kontrol gruplu yarı deneysel desen kullanılmıştır. Nitel verilerin toplanmasında; hücre ve bölünmeler ünitesi başarı testi, fen öğrenmeye yönelik motivasyon ölçeği ve düşünce tarzı ölçeği kullanılmıştır. Elde edilen veriler SPSS paket programı yardımı ile analiz edilmiştir. Araştırmada elde edilen verilerin analizi ile ulaşılan bulgular doğrultusunda gelişim öz-teorisine göre tasarlanan etkinliklerin öğrencilerin gelişime açık düşünce tarzı seviyesini artırdığı görülmüştür. Ayrıca deney grubu öğrencilerinin hücre ve bölünmeler ünitesine ait akademik başarı ve fen öğrenmeye yönelik motivasyonlarının, kontrol grubundaki öğrencilerin akademik başarı ve motivasyonlarından daha yüksek olduğu, dolayısı ile uygulanan etkinlerin öğrencilerin hücre ve bölünmeler ünitesine ait akademik başarılarını ve fen öğrenmeye yönelik motivasyonlarını artırıcı yönde etki ettiği tespit edilmiştir.
Proposta de roteirização para utilização de parques urbanos como instrumentos pedagógicos de Educação Ambiental
Authors: Miranda Cavalcante Ivânia , Ten Caten Pipe Roselaine r , Nora Giseli Dalla
Published: May 2021

O rápido crescimento da cidade de Cuiabá, de forma não planejada, criou os diversos tipos de desequilíbrio e impactos ambientais. O Parque Massairo Okamura é uma Unidade de Conservação que pode ser utilizada como proposta educativa para trabalhar a educação ambiental, na formação de futuros cidadãos conscientes, no ensino aplicado, entendedores do espaço em que vivem e de sua relação sociedade/natureza. O presente trabalho tem como objetivo propor um roteiro para a utilização do Parque Massairo Okamura como instrumento pedagógico de educação ambiental, por meio de roteiros de campo para trabalhar a interdisciplinaridade, oportunizando ao aluno o contato direto com o meio ambiente e melhor entendimento do conteúdo aplicado em sala de aula. Com a metodologia qualitativa e visitas de campo, sugere-se, aqui, um roteiro de aula de campo com aproximadamente nove pontos de observação para abordarem-se as questões relacionadas com a educação ambiental e interdisciplinaridade. Neste contexto, observa-se que tal parque pode ser utilizado como importante instrumento pedagógico de educação ambiental.
Un Planeta, unha saúde. Facendo a paz coa Terra
Authors: Organizacións Varias
Published: May 2021

A pandemia do virus Corona Covid-19 é unha chamada de atención planetaria da Terra á humanidade.Lémbranos que somos un coa Terra, non estamos separados dela, que non somos os seus donos, donos e conquistadores, nin que somos superiores a outras especies, como o dogma antropocéntrico que nos queren facer crer.A pandemia lémbranos que violamos os dereitos da Terra e de todas as súas especies pola nosa conta e risco e que sería prudente que considerásemos o coñecemento ancestral e a sabedoría dos pobos indíxenas, gardiáns da Terra ao longo do tempo, cuxos o profundo respecto pola Terra baséase na conciencia da interconectividade de toda a vida. Danar unha peza significa danar a totalidade.Esta pandemia non é un “desastre natural”, do mesmo xeito que a crise de extinción de especies e os extremos climáticos non son “desastres naturais”. As epidemias de enfermidades emerxentes son antrópicas, causadas por actividades humanas.
An Overview of Qualitative Research and Focus Group Discussion
Authors: TÜMEN AKYILDIZ Seçil , AHMED Kwestan Hussein
Published: May 2021

Recently, qualitative studies have been widespread in various areas such as, psychology, business, and sociology. In this review, the process of qualitative study has been clarified with the aim of offering a description of its general process. Basically, the qualitative investigation is exploratory, which indicates an understanding of the results made by the researcher(s). Likewise, designing a research is a process or guideline utilized to prepare, implement, and evaluate an idea that the researchers want to reveal about an issue. It is also a plan to answer the problems or concepts of an investigated study. Since qualitative studies help researchers to examine opinions, attitudes, and perspectives of human beings, so it has gained more attention in many fields and especially in the area of social sciences. Accordingly, the qualitative study focuses on how individuals perceive and give meaning to different social behaviors in order to explore people’s social observations. This study aims to reveal the qualitative research process and how the data would be collected via this approach. The researchers attempt to announce the significance of the qualitative study and focus group discussion tool (advantages and limitations as well) to propose a better understanding for the academics who want to utilize a qualitative study in social sciences.
Experimental Study of the Efficiency of a Solar Water Heater Construction from Recycled Plastic Bottles
Authors: Chekchek Besma , Salmi Mohamed , Boursas Abdelhakim , Lorenzini Giulio , Ahmad Hijaz , Menni Younes , Ameur Houari , Merrah Merzaqa , Fridja Djamal
Published: May 2021

A solar polymer heat exchanger is designed to heat water; its primary materials are plastic water bottles with a capacity of 1.5 liters. These materials were recycled to preserve the environment and to make use of it again. The thermal insulation properties are adopted for the characterization of polymeric materials. These properties concern the conservation of energy for the longest period of time and the absence of problems caused by rust and corrosion, which are usually encountered in traditional heat exchangers. The heat exchanger experiments start by tracking the flow of water inside the pipes by a valve. The water temperature and flow rates are determined at the inlet and outlet surfaces of the exchanger. The obtained results indicated an increase in water temperature exceeding 10℃ in an ideal spring day. The thermal efficiency of the solar collector was about 62% under the sunlight, and 44% in the laboratory where halogen lamps were used as an industrial light source.
Mapa mental interativo: a concepção de uma mídia rica para a aprendizagem
Authors: Tavares Luis Antonio , Meira Matheus Carvalho , Do Amaral Sérgio Ferreira
Published: May 2021

Este artigo explora as características do mapa mental como ferramenta pedagógica e demonstra o uso de tecnologia e interatividade para potencializar o uso deste recurso. Desenvolvemos um protótipo de um mapa mental interativo para demonstrar recursos de visualização que podem agregar valor à ferramenta. Os mapas mentais podem se constituir como mídias ricas, uma vez que permitem incorporar diferentes tipos de mídias, possibilitando atingir estudantes com diferentes perfis e necessidades de aprendizagem. Neste sentido, o trabalho demonstra aplicações e vantagens dos mapas mentais como uma ferramenta para uma metodologia ativa, favorecendo a interação do discente e sua participação na construção do seu conhecimento, também, aliando o aspecto tecnológico como forma de aproximação entre a escola e a realidade dos estudantes.
Estratégias de leitura recorridas por professoras iniciantes na educação infantil
Authors: Ciríaco Klinger Teodoro , Barreto Fernanda Alves , Alves Thiago Moessa , Souza Renata Junqueira de
Published: May 2021

Trabalhar estratégias de leitura desde a pequena infância torna-se um dos pressupostos teóricos que direcionaram o trabalho de pesquisa relatado neste artigo. Para este fim, tivemos como base de estudo uma investigação qualitativa, de caráter descritivo-analítico, em que duas professoras em início de carreira na Educação Infantil foram fonte direta de coleta de dados. Objetivamos compreender quais são as estratégias de leitura adotadas por professoras de bebês e de crianças pequeninas (0 a 3 anos), bem como as dificuldades presentes na estruturação deste tipo de prática pedagógica. O referencial teórico adotado possibilitou agrupar a compreensão das principais dificuldades do professor iniciante e da importância de promover a linguagem oral e escrita na infância. Em termos metodológicos, a fonte de recolha das informações, tanto nas observações quanto nas entrevistas concedidas, auxiliou na efetivação dos objetivos propostos inicialmente. A conclusão permite inferir que é possível um trabalho com estratégias de leitura quando a professora envolve as crianças no contexto da narrativa, ao articular seus conhecimentos prévios, por meio de inferências e da sumarização das histórias que elege como fonte de acesso à leitura da literatura infantil.