bluuebunny/crossref_metadata_2025 huggingface dataset:
Detection of antipersonnel landmines containing ANFO-based explosive: A review
Authors: Sierra Cesar , Perez Leon , Garzon Andrea , Hinestroza Juan , Sinuco Diana
Published: November 2020

After an internal conflict that lasted over half a century, the detection and removal of antipersonnel landmines in Colombia have become cumbersome challenges. Antipersonnel landmines remain scattered in Colombia and with a considerable impact on the central-western region. Most of these devices are handmade (therefore, they can also be classified as improvised explosive devices) and composed of ammonium nitrate and fossil fuel blend, a mixture known as ANFO. Due to several unique factors, including concealment tactics and non-conventional manufacturing techniques employed by guerrilla fighters, the most efficient method for the detection of ANFO-based antipersonnel landmines is the use of trained canines. This review aims at describing the current chemical strategies used in the detection of ANFO-based antipersonnel landmines. First, a detailed description of the different techniques used in the detection of explosives is made. Then, all the strategies reported in the world for antipersonnel landmines detection are described. Finally, the importance of the use of canines for antipersonnel landmines detection is explained.
Influencia de un campo magnético oscilante en columnas poliméricas con nanopartículas magnéticas (ARTÍCULO RETRACTADO)
Authors: Dalgo Flores Violeta Maricela , Chango-Lescano Gabriela Cristina , Vera-Luzuriaga John Germán
Published: November 2020

ARTÍCULO RETRACTADO
Las nanopartículas magnéticas de magnetita (MNP) presentan comportamiento superparamagnético, lo que les confiere propiedades importantes como bajo campo coercitivo, fácil modificación superficial y niveles de magnetización aceptables. Esto las hace útiles en técnicas de separación. Sin embargo, pocos estudios han experimentado con las interacciones de las MNP con campos magnéticos. Por tanto, el objetivo de esta investigación fue estudiar la influencia de un campo magnético oscilante (CMO) en columnas monolíticas poliméricas con nanopartículas magnéticas vinilizadas (VMNP) para cromatografía líquida capilar (cLC). Para ello, se sintetizaron MNP mediante coprecipitación de sales de hierro. La preparación de las columnas monolíticas poliméricas se realizó por copolimerización y la agregación de VMNP. Aprovechando las propiedades magnéticas de las MNP, se estudió la influencia de los parámetros como frecuencia de resonancia, intensidad y tiempo de exposición de un CMO, aplicado a las columnas sintetizadas. Como resultado se obtuvo una mejor separación de una muestra según los parámetros medidos, de modo que se logró una resolución de la columna (Rs) de 1,35. Las propiedades morfológicas de las columnas fueron evaluadas mediante microscopía electrónica de barrido (SEM). Los resultados de las propiedades cromatográficas revelaron que la mejor separación de la muestra de alquilbencenos se da en condiciones de 5,5 kHz y 10 min de exposición en el CMO. Este estudio constituye una primera aplicación en técnicas de separación cromatográficas para futuras investigaciones en nanotecnología.
Caracterización de los parámetros biométricos oculares de pacientes colombianos candidatos a cirugía de catarata
Authors: Paulo Jose David , Hurtado Luis Santiago , Donado-Gomez Jorge Hernando , González-Lopera Natalia
Published: November 2020

Introducción. El cálculo del poder del lente intraocular (LIO), basado en la biometría ocular, es un factor determinante del éxito en la cirugía de catarata.
Objetivos. Caracterizar los parámetros biométricos oculares de pacientes colombianos mayores de 40 años candidatos a cirugía de catarata y determinar la prevalencia de las 9 condiciones clínicas propuestas por Holladay según la interacción entre longitud axial (LA) y profundidad de la cámara anterior (ACD).
Materiales y métodos. Estudio transversal analítico. Se revisaron los resultados de biometría ocular de 781 pacientes (831 ojos) que iban a ser sometidos a cirugía de cataratas entre enero de 2014 y enero de 2015 en Medellín, Colombia. Luego de aplicar los criterios de exclusión, se incluyeron 716 ojos para análisis. Se recolectaron datos sobre edad, sexo, LA, queratometría (queratometría más plana (K1), queratometría más curva (K2)), ACD y distancia blanco-blanco. Los resultados se presentan mediante estadística descriptiva.
Resultados. La mayoría de ojos eran de mujeres (62.3%). Las medias de LA, K1 y ACD fueron 23.37±1.51mm, 43.52±2.06 y 3.03±0.41mm, respectivamente. La media de LA en hombres fue 23.62±1.37mm, y en mujeres, 23.21±1.67mm. La media más alta de LA se observó en pacientes <50 años (23.84±2.41mm) y la más baja en aquellos ≥80 años (22.96±1.03mm). Respecto al tamaño de los ojos según su LA, 90.5% fueron normales; 4.89%, largos, y 4.61%, cortos.
Conclusiones. 85% de los participantes tuvo parámetros biométricos normales. Para el 15% restante es necesario tomar precauciones al calcular el poder del LIO, tales como el uso de fórmulas de cuarta generación como la Holladay 2 en ojos largos, pues en estos pacientes no se obtendrá el mismo comportamiento refractivo con las fórmulas de predicción tradicionales. Además, según la clasificación de Holladay, excluyendo a los ojos normales, los ojos más frecuentes fueron aquellos con miopía e hipermetropía axial.
Validación de la versión chilena del cuestionario “Workplace Violence in the Health Sector” en la atención prehospitalaria
Authors: Rodríguez-Campo Varinia Alejandra , Paravic-Klijn Tatiana María
Published: November 2020

Introducción. La violencia laboral es cada día más frecuente en el sector de la salud. Por ello, se requieren instrumentos válidos y confiables para poder medir este fenómeno.
Objetivo. Validar la estructura factorial de la versión traducida al español del cuestionario “Workplace Violence in the Health Sector” en trabajadores de la atención prehospitalaria de Chile.
Material y métodos. Estudio cuantitativo-multivariado. Se realizó un análisis de componentes principales (ACP) de la versión traducida al español del cuestionario. Luego de ser revisada por expertos y de realizar una prueba piloto, se eliminaron 6 preguntas y la versión adaptada fue aplicada a 74 profesionales sanitarios (enfermeros-kinesiólogos) y 148 técnicos paramédicos que trabajaban en atención prehospitalaria. Para el análisis de los datos se aplicó estadística descriptiva y estadística inferencial (prueba χ²). El programa SPSS v15 se utilizó para realizar el análisis de los datos y el ACP.
Resultados. El cuestionario tuvo una alta confiabilidad total (α=0.912). De acuerdo con el ACP se evidenciaron tres factores —violencia física (valor propio: 8.3), abuso verbal (valor propio 3.7) y mobbing o acoso laboral (valor propio: de 3.6)— que explican el 86% de la varianza.
Conclusiones. El instrumento propuesto es válido para medir la violencia laboral en personal de la salud que se desempeña en atención prehospitalaria. Además, contar con una herramienta validada que permita cuantificar este fenómeno en el país es un aporte significativo, pues es posible realizar estudios similares en otras áreas de la salud y, a partir de sus resultados, trabajar en su prevención y en la promoción de ambientes laborales más saludables.
Evaluación continua de la calidad metodológica de las guías de práctica clínica como una necesidad urgente
Authors: Ángel-Ángel Gustavo Adolfo
Published: November 2020

Querido editor:
Las guías de práctica clínica (GPC) son documentos que, con base en revisiones sistemáticas de la literatura y en pro de brindar herramientas para mejorar los estándares de atención en salud, sintetizan la mejor evidencia disponible y establecen recomendaciones de manejo para diferentes patologías en escenarios específicos.1 En este contexto, y debido a la utilidad de las GPC en el propósito de mejorar los estándares de calidad de la atención en salud, muchas entidades gubernamentales contratan grupos de expertos temáticos y metodológicos para su elaboración.
Factores asociados a la satisfacción laboral del profesorado universitario
Authors: Limaymanta Cesar H. , Turpo-Gebera Osbaldo
Published: November 2020

El ámbito laboral debe estar ligado a lo que nos motiva y nos apasiona, dado que involucra gran parte de nuestras vidas. El propósito de este artículo se centró en analizar los factores asociados a la satisfacción laboral del profesorado de una universidad pública y de otra privada ubicadas en Lima, Perú. Se empleó la metodología cuantitativa con diseño no experimental de corte transversal y nivel de estudio correlacional. Los datos fueron recolectados en 2018 a través de un cuestionario adaptado sobre satisfacción laboral, que cumple con las propiedades de validez y confiabilidad. La muestra estuvo conformada por 98 docentes en la categoría de ordinarios. El tratamiento de los datos se basó en el uso de las técnicas de la estadística descriptiva e inferencial, como la prueba t, U de Mann-Whitney, ANOVA y la correlación de Spearman. Los resultados evidencian que el reconocimiento, las condiciones de trabajo, el logro, la compensación y las oportunidades de promoción se asocian con la satisfacción laboral, mientras que los factores sociodemográficos y académicos, como grupo etario, sexo, formación académica y categoría laboral no se asocian con ella. Además, se evidenció que no existe diferencia entre los niveles de satisfacción laboral del personal docente de ambas universidades. Por último, se presentan posibles alcances y propuestas para mejorar los niveles de satisfacción laboral del profesorado universitario.
Mensajería en Wasap y millennials universitarios de Cotopaxi, desafíos para la educación superior de Ecuador
Authors: Gómez-Castells Máximo Ricardo , Venegas Álvarez Gina Silvana , Mena Vargas Nelly Patricia
Published: November 2020

Con el objetivo de realizar un acercamiento a la mensajería que el estudiantado revela en Wasap desde la perspectiva del interpretante y establecer los desafíos que ello representa para la Educación Superior en Ecuador se efectúa la investigación, tal propósito constituye la aportación a una revelación de los efectos producidos en el discurso receptivo cuya lectura transita por la sociolingüística, la filosofía del lenguaje y la pragmática, la convergencia de tales argumentos en el ámbito pedagógico es una posibilidad para la enseñanza desde el discurso digital. En este artículo se ofrece una exploración de la relación potencial entre el uso de la mensajería instantánea y la conformación de interpretantes sobre la base del establecimiento de presupuestos teóricos y metodológicos de la sociolingüística en millennials universitarios de la Carrera de Pedagogía de los Idiomas Nacionales y Extranjeros de la Universidad Técnica de Cotopaxi en Ecuador. La investigación fue de tipo exploratorio y una metodología cualitativa en que se implementó una estrategia de complementariedad de los métodos y técnicas de análisis de documentos, entrevista grupal e individual, encuesta y el análisis hermenéutico del discurso. La muestra fue seleccionada mediante el muestreo no probabilístico, por lo que se conformó un grupo de 10 estudiantes. Los resultados revelaron la serie de interpretantes que generan los millennials universitarios ecuatorianos y las variaciones lingüísticas que tipifican su discurso; información de donde se extrajeron las reglas presentes en la recepción, así como una taxonomía de los interpretantes presentes en la plataforma digital estudiada constitutiva de un modelo de discurso como síntesis de la mensajería instantánea utilizada por los estudiantes. En esta Mensajería se configuran interpretantes que revelan su creatividad significativa, de la cual se derivaron consideraciones acerca de la necesidad de generación de procedimientos de enseñanza basados en la trilogía de Peirce donde el estudiantado forme capacidades cognoscitivas sobre la trascendencia del imaginario lingüístico en el enriquecimiento de la lengua.
Generic solicitude in sequence-initial position as a practice for pre-closing proposals in Mandarin telephone calls
Authors: Dong Boyu , Wu Yaxin
Published: November 2020

Based on 200 mundane Mandarin Chinese telephone calls, this article describes the composition of generic solicitude in sequence-initial position in the closing section of telephone calls. Two types of generic solicitude are found, namely, stand-alone generic solicitude and composite generic solicitude. Stand-alone generic solicitudes are found in single unit turns and usually occur in imperatives like Adj + dianr + V. The recipients frequently accept the generic solicitude by displaying minimal response followed by a terminal sequence. Composite generic solicitudes occur in multi-unit turns which include closing components and generic solicitudes. The recipients may accept or reject the pre-closing proposal by way of a composite generic solicitude. The generic solicitude could be expanded by both participants. The article concludes that generic solicitude is a practice for pre-closing proposals in Mandarin telephone calls. Generic solicitudes in the closing section of a telephone call function to establish the closing-relevant environment and reaffirm relationship work. This article contributes to our understanding of the organisation of telephone closings in Mandarin interaction.
Lycopene activity on lung and kidney cancer cells by T2 relaxation time 1H Magnetic Resonance Imaging in vitro
Authors:   Centre for Innovative Research in Medical and Natural Sciences, Medical College of University of Rzeszow, Rzeszow, Poland, Pogoda Katarzyna , Pucka Maria ,   Centre for Innovative Research in Medical and Natural Sciences, Medical College of University of Rzeszow, Rzeszow, Poland, Tabarkiewicz Jacek ,   Centre for Innovative Research in Medical and Natural Sciences, Medical College of University of Rzeszow, Rzeszow, Poland, Bober Zuzanna ,   Department of Photomedicine and Physical Chemistry, Medical College of University of Rzeszów, Rzeszów, Poland, Aebisher David ,   Department of Photomedicine and Physical Chemistry, Medical College of University of Rzeszów, Rzeszów, Poland, Galiniak Sabina ,   Department of Biochemistry and General Chemistry, Medical College of University of Rzeszów, Rzeszów, Poland, Bartusik-Aebisher Dorota ,   Department of Biochemistry and General Chemistry, Medical College of University of Rzeszów, Rzeszów, Poland
Published: November 2020

Introduction. The paper presents the results of a study of cell cultures of lung cancer and kidney cancer using lycopene performed using clinical magnetic resonance imaging. Aim. The aim of the study was to evaluate lycopene activity on tumor cell cultures. Material and methods. For this purpose, MR tests were performed using the technique of determining transverse relaxation. Results. Described here studies demonstrated that lycopene may inhibit the growth of A549 and ACHN cell lines. Conclusion. We determine changes in spin lattice relaxavity T2 to monitor treatment of lung cancer cell line A549 and kidney cancer cell line ACHN cells treatment with lycopene.
Splenic hydatidosis with abdominal pain – a rare presentation in a developing nation
Authors:   Department of Pathology and General Surgery, Jawaharlal Nehru Medical College, A.M.U., Aligarh, India, Akhtar Kafil , Alam Saquib ,   Department of Pathology and General Surgery, Jawaharlal Nehru Medical College, A.M.U., Aligarh, India, Rab Atia Zaka-ur ,   Department of Pathology and General Surgery, Jawaharlal Nehru Medical College, A.M.U., Aligarh, India, Sherwani Rana K ,   Department of Pathology and General Surgery, Jawaharlal Nehru Medical College, A.M.U., Aligarh, India
Published: November 2020

Introduction. Primary extrahepatic hydatid cysts are rare, and primary splenic hydatid cysts even rarer. Splenic hydatidosis constitutes 2% to 3.5% of all hydatid cysts. Aim. To present a case report of splenic hydatidosis with abdominal pain. Description of the case. We report here a case of isolated splenic hydatid cysts in a 23 year old female, who presented with dull dragging pain in the left hypochondrium. Diagnosis was made on computed tomography imaging of the abdomen and microscopic examination of the laminated hydatid cyst wall and supplemented with positive enzyme linked immunosorbent assay for hydatid antibodies. Conclusion. The incidence of splenic involvement by hydatid cysts is very low. Man is an accidental intermediate host, as entry of the larval forms into humans represents an end stage in its life cycle. Until recently the gold standard treatment for splenic hydatidosis was splenectomy, as medical therapy seems to be ineffective. However, the last two decades have shown a tendency towards splenic conservative surgery in suitable cases, to reduce opportunistic post splenectomy infection.
Atypical extra nasopharyngeal angiofibroma in an unusual location: tonsil posterior pillar (oropharynx)
Authors:   All India Institute of Medical Sciences, Rishikesh, Uttarakhand, India, Mittal Shweta , Priya Madhu ,   All India Institute of Medical Sciences, Rishikesh, Uttarakhand, India, Varshney Saurabh ,   All India Institute of Medical Sciences, Rishikesh, Uttarakhand, India, Angral Sumeet ,   All India Institute of Medical Sciences, Rishikesh, Uttarakhand, India, Xavier Joyson ,   All India Institute of Medical Sciences, Rishikesh, Uttarakhand, India, Malhotra Manu ,   All India Institute of Medical Sciences, Rishikesh, Uttarakhand, India, Bhardwaj Abhishek ,   All India Institute of Medical Sciences, Rishikesh, Uttarakhand, India, Kumar Amit ,   All India Institute of Medical Sciences, Rishikesh, Uttarakhand, India, Tyagi Amit Kumar ,   All India Institute of Medical Sciences, Rishikesh, Uttarakhand, India
Published: November 2020

Introduction. Angiofibroma is a benign, locally aggressive highly vascular tumor that typically affects young adolescent males and has a pathognomonic epicenter of origin in the nasopharynx. The atypical angiofibromas share the same histological features as that of Juvenile nasopharyngeal angiofibroma, however they differ significantly in their clinical features. Aim. Here we are reporting a very rare case of atypical angiofibroma in an adult male presenting as a non-vascular mass in the oropharynx with posterior pillar as the subsite. Description of the case. A 26-years old male patient presented with chief complaints of foreign body sensation and mass in throat for one and a half months which was gradually progressive in size. Histopathological examination revealed a lesion with an intricate mixture of blood vessels, irregular fibrous stroma with loose edematous and fibrous area along with multinucleated stromal cells which was suggestive of angiofibroma. Conclusion. Oropharyngeal angiofibroma, being an atypical angiofibroma in terms of site and presenting complaints, presents a diagnostic challenge. Though rare, it should always be kept as a differential diagnosis in any oropharyngeal mass irrespective of its vascularity, typical age or sex of the patient.
Parotid pilomatrixoma: Diagnostic trap and management dilemma
Authors:   Department of Otorhinolaryngology & Head-Neck Surgery, All India Institute of Medical Sciences, Rishikesh, India, Bhardwaj Abhishek , Angral Sumeet ,   Department of Otorhinolaryngology & Head-Neck Surgery, All India Institute of Medical Sciences, Rishikesh, India, Chandra Sharath ,   Department of Otorhinolaryngology & Head-Neck Surgery, All India Institute of Medical Sciences, Rishikesh, India, Malhotra Manu ,   Department of Otorhinolaryngology & Head-Neck Surgery, All India Institute of Medical Sciences, Rishikesh, India, Priya Madhu ,   Department of Otorhinolaryngology & Head-Neck Surgery, All India Institute of Medical Sciences, Rishikesh, India, Varshney Saurabh ,   Department of Otorhinolaryngology & Head-Neck Surgery, All India Institute of Medical Sciences, Rishikesh, India, Singh Arpana ,   Department of Microbiology, All India Institute of Medical Sciences, Rishikesh, India, Raj Ritu ,   Department of Otorhinolaryngology & Head-Neck Surgery, All India Institute of Medical Sciences, Rishikesh, India,   Department of Medicine, All India Institute of Medical Sciences, Rishikesh, India
Published: November 2020

Introduction. Pilomatrixoma is a benign cutaneous adnexal neoplasm originating from the matrix cells of the hair follicles. Usually a slow growing and painless lesion, it must be considered in differential diagnosis of a preauricular swelling. Rapidly progressive lesion with skin fixity and missed subtle cytological features may lead to a misdiagnosis of parotid neoplasm resulting in management dilemma. Aim. This report emphasizes consideration of pilomatrixoma as a differential diagnosis in a similar clinical scenario, the role of frozen section during surgery and fascia lata interposition to prevent Frey’s syndrome. A brief review of literature is presented. Description of the case. We present a similar dilemmatic case of a 19 years old male with preauricular swelling. Based on cytology and image findings, a diagnosis of parotid neoplasm with possible malignancy was made. Surgical exploration revealed primarily a subcutaneous lesion with partial attachment to superficial surface of parotid. Lesion was excised with a cuff of normal parotid tissue. Frozen section confirmed it to be a nonmalignant lesion with possibility of pilomatrixoma. Fascia lata was interposed between parotid and thin skin flap to avoid gustatory sweating. Patient is on follow up for 6 months without recurrence or any complication. Conclusion. Pilomatrixomas can be misdiagnosed in case of lesions in subcutaneous plane in parotid region. In such cases, the differential diagnosis should include tumor and non-tumor lesions of skin and parotid gland. Importance of frozen section should also be kept in mind and the pathologist should be engaged at the time of surgical excision of the tumor. Interposition of soft tissue between parotid and thin skin flap helps prevent gustatory sweating in such cases. A high index of suspicion is needed for proper diagnosis and management of these lesions.
External ophthalmomyiasis by sheep botfly – a report from Sirmaur hills
Authors:   Department of Ophthalmology, Dr Yashwant Singh Parmar Govt. Medical College, Nahan, District Sirmour, Himachal Pradesh, India, Chauhan Anubhav , Gautam Neha ,   Department of Microbiology, Dr Yashwant Singh Parmar Govt. Medical College, Nahan, District Sirmour, Himachal Pradesh, India
Published: November 2020

Introduction. Myiasis is caused by larvae of flies infesting animal or human tissues and organs. Aim. In this report we present 2 cases of external ophthalmomyiasis by sheep botfly. Description of the cases. We report a case of two patients who presented with a history of foreign body sensation in the left and the right eye respectively. Slit lamp examination revealed larvae of Oestrus ovis (sheep botfly). In both cases, there was no contact history with sheep or goats. Signs of conjunctival inflammation and corneal involvement were absent in both cases. In most of the previous reports, corneal and conjunctival inflammation was present. Conclusion. Treatment for external ophthalmomyiasis is based on larvae removal and application of topical antibiotics and steroids.
The potential of intracellular 13C MR spectroscopy to study the absolute configuration of endogenous and polarized alanine
Authors:   Department of Human Anatomy, Medical College of Rzeszów University, Rzeszów, Poland, Leksa Natalia , Pękala Anna ,   Department of Gastroenterology with IBD Unit, Clinical Hospital No. 2, Rzeszów, Poland, Pardak Piotr ,   Department of Gastroenterology with IBD Unit, Clinical Hospital No. 2, Rzeszów, Poland,   Department of Gastroenerology, Medical College of Rzeszów University, Rzeszów, Poland, Dziedzic Rafał ,   Department of Neurosurgey, Hospital MSWiA, Rzeszow, Poland, Bartusik-Aebisher Dorota ,   Department of Biochemistry and General Chemistry, Medical College of Rzeszów University, Rzeszów, Poland, Filip Rafał ,   Department of Gastroenterology with IBD Unit, Clinical Hospital No. 2, Rzeszów, Poland,   Department of Gastroenerology, Medical College of Rzeszów University, Rzeszów, Poland, Galiniak Sabina ,   Department of Biochemistry and General Chemistry, Medical College of Rzeszów University, Rzeszów, Poland, Aebisher David ,   Department of Photomedicine and Physical Chemistry, Medical College of Rzeszów University, Rzeszów, Poland
Published: November 2020

Introduction. Quantitative and accurate monitoring of tumor makes hyperpolarized carbon (13C) Magnetic Resonance Imaging and Spectroscopy (MRI/S) a powerful tool for in vivo metabolic and structural study. Moreover, the studies of the properties and functions in tumor tissue of the compounds of carbon (C) that are organic, are fundamental to tumor biochemistry. Aim. To review 13C MR spectroscopy to study the absolute configuration of endogenous and polarized alanine Material and methods. An analysis of literature regarding 13C MR spectroscopy of polarized alanine. Results. Current evidence suggests that the determination of absolute configurations of amino acids play significant role in physiological mechanisms during tumor growth and treatment. Conclusions. Nearly 50% nuclear polarization for 13C can be achieved in various organic molecules when Dynamic Nuclear Polarization DNP is performed in a strong magnetic field and at cryogenic temperatures.
HBV Hepatitis and Related Renal Nephropathies: Pathogenesis and Treatment
Authors: Salvadori Maurizio , Tsalouchos Aris
Published: November 2020

The extrahepatic manifestations of hepatitis B virus (HBV) infection include reactive arthritis, vasculitis (panarteritisnodosa), and primary glomer-ulonephritis (membranous nephropathy, membranoproliferative glomerulonephritis, and, less frequently, IgA nephropathy, focal and segmental glomerulosclerosis, and minimal change disease). No specific histomorphological patterns have been reported in association with HBV infection. The treatment of HBV-related glomerulopathies is essentially antiviral. Peginterferon and nucleos(t)ide drugs are the treatment of choice. Cortico-steroids have been proved to be ineffective (except in panarteritisnodosa), while immunosuppressants can lead to exacerbation of HBV infection.
Quantifying the Emergence Profile Contour for Immediate Provisionalization: A Proposed Mathematical Model
Authors: El Chaar Edgard , White Cecilia , Salama Toni , Andrawis Andrew
Published: November 2020

Identifying the ideal position of the final restoration prior to implant surgery is essential for optimal esthetics. The study of the emergence contour design of implant restorations has been limited. The aim of this report is to compile the factors that affect the final esthetic outcome and integrate those factors into an easy-to-use model. This geometric model includes a linear distance created by the placement of an implant platform in relation to the free gingival margin and a circle representing the emergence profile to create an emergence curve. If this model is evaluated and available, a practitioner can make appropriate decisions based on 3-dimensional immediate implant concepts.
Elementos lingüísticos que obstaculizan la correcta construcción textual crítica
Authors: García Villalba Cristian , Lasso  Avendaño Janeth
Published: November 2020

Una de las principales problemáticas académicas tanto para las instituciones educativas y estudiantes a lo largo de su proceso académico, es el desarrollo de una lectura crítica que permite entender, interpretar y evaluar un tema o situación, y que a la vez condiciona la construcción escrita del estudiante, resultado de la misma. Por esta razón, el presente artículo plantea como objetivo principal analizar los diferentes obstáculos lingüísticos a los que se enfrentan los estudiantes de segundo semestre de Comunicación Social y Periodismo de la Universidad Minuto de Dios (UNIMINUTO), que alteran en gran medida la buena intención comunicativa crítica de sus escritos. Lo anterior, desde una metodología cualitativa y un diseño cuasiexperimental, se abordó para dar cuenta de las necesidades académicas de los estudiantes, las cuales deben ser imperantes desde la educación básica y media, antes de llegar a los entornos profesionales y más tarde laborales. Se concluyó que aun cuando los estudiantes cuentan con una buena lectura crítica, en el momento de concretarla de manera escrita, evidencian un manejo deficiente de elementos lingüísticos lo que conlleva a la alteración del mensaje. Lo anterior hace fundamental el papel de las instituciones educativas en la generación de estrategias de intervención pedagógica que garanticen la formación comunicativa integral: lectura y escritura.
Adaptación chilena de la Escala de Bienestar Adolescente EPOCH
Authors: Ortiz Paulina , Leiva Gutiérrez Jose , Proestakis Alejandro
Published: November 2020

Existe en la actualidad un creciente interés de la promoción del bienestar en los contextos educativos, lo que ha llevado a diversos autores a proponer modelos para evaluar el bienestar y la creación de instrumentos en esta línea. Uno de los instrumentos utilizado para evaluar bienestar adolescente es la escala EPOCH, basada en el modelo PERMA y que comprende las dimensiones de engagement, conectividad, felicidad, optimismo y perseverancia.  La presente investigación tuvo por objetivo adaptar la Escala de Bienestar Adolescente EPOCH elaborada por Peggy Kern, Lizbeth Benson, Elizabeth A. Steinberg y Laurence Steinberg (2016). Se recolectaron datos de 1558 estudiantes entre 11 y 18 años de edad, pertenecientes a cuatro establecimientos educativos de la región de Antofagasta, Chile. Se estudió la capacidad discriminatoria de los ítems, así como también la estructura factorial del instrumento. Los resultados obtenidos muestran un comportamiento psicométrico aceptable y una estructura similar a la planteada por las autoras. Podemos concluir que la escala EPOCH es una herramienta útil para la evaluación del Bienestar de Adolescentes, en contextos educativos chilenos.
La evaluación docente en México: el caso de la educación media superior
Authors: Lozano Medina Andrés
Published: November 2020

A partir de la creación del Servicio Profesional Docente (SPD) en 2013, a la evaluación que se aplica a los docentes de educación básica y media superior se le agregaron tres momentos laborales más que se refieren al ingreso, la permanencia y la promoción de los docentes y directivos, en este sentido, el objetivo de este documento es presentar avances en la sistematización de los resultados obtenidos por los docentes de educación media superior a través de las diversas evaluaciones realizadas por la instancia mencionada; lo anterior, a partir de la revisión documental de diversas fuentes para el tratamiento de la información y su valoración. Los resultados encontrados refieren que la profesionalización docente en los tres espacios laborales en que se lleva a cabo presenta serias limitaciones en lo logrado, considerando las diferentes evaluaciones; con ello es posible determinar que los resultados de estas evaluaciones no han logrado establecer indicadores que aseguren que la mejora de la calidad educativa, ofrecida en la educación media superior en México, sea posible en los términos señalados por la política educativa vigente debido a que los docentes no han superado los indicadores solicitados por el SPD.
Longing to Belong: Mentoring Relationships as a Pathway to Fostering a Sense of Belonging for Racially Minoritized Faculty at Predominantly White Institutions
Authors: Wright-Mair Raquel
Published: November 2020

As predominately white institutions (PWIs) seek to support racially minoritized faculty, there is evidence that racially minoritized faculty members at PWIs experience isolating, hostile, and unwelcoming environments (Bonner et al., 2014; Stanley, 2006; Turner, 2003). Existing higher education research does not explore the significance of sense of belonging for racially minoritized faculty and ways in which sense of belonging can be cultivated in these neoliberal institutions. Through a critical race theory lens and phenomenological method, this study focuses on ways in which mentoring relationships develop pathways to sense of belonging for racially minoritized faculty members at PWIs. Findings reveal a robust network of mentoring relationships for racially minoritized faculty, including holistic and critically conscious mentoring by colleagues, supportive peer mentoring, mentoring students, and community-based mentoring relationships. Implications for research and practice are outlined to further explore how these crucial relationships can develop sense of belonging for racially minoritized faculty members at PWIs.
Role of crystalline silica admixture in mitigating ettringite-induced heave in lime-treated sulfate-rich soils
Authors: Chakraborty Sayantan , Puppala Anand J. , Biswas Nripojyoti
Published: November 2020

A research study was designed and conducted to evaluate the applicability of using crystalline silica-rich material as a co-additive with calcium-based stabilisers to treat sulfate-rich expansive soils. Extensive laboratory tests were conducted on lime-treated sulfate-rich soils, with and without crystalline silica admixture, to evaluate the improvements in engineering properties, including swell strain, unconfined compressive strength and resilient moduli properties. The influence of co-additive dosage, curing period and duration of moisture exposure was studied to gain insights into the behaviour of treated soils. Supplementary mineralogical and microstructural studies including X-ray diffraction, scanning electron microscope imaging and differential scanning calorimetry studies were performed on the treated soils to detect the formation of ettringite mineral and cementitious gel compounds. Test results indicated that the use of crystalline silica facilitated enhancement of both the strength before and after capillary soaking, and the resilient moduli properties, while suppressing ettringite mineral formation and associated free swell strains in the treated soils. Mineralogical and engineering studies showed the dominance of pozzolanic activity between lime and crystalline silica over ettringite formation and hence contributed to the effective stabilisation of sulfate-rich soils. Overall, the paper provides a comprehensive understanding of the role of crystalline silica admixture for mitigating deleterious sulfate heaving in lime-treated soils.
Nanostructured strain hardened aluminum-magnesium alloys modified by C60 fullerene obtained by powder metallurgy. Part 1. Effect of magnesium concentration on the structure and phase composition of powders
Authors: Evdokimov I. A. , Khayrullin R. R. , Bagramov R. Kh. , Aksenenkov V. V. , Perfilov S. A. , Pozdnyakov A. A. , Kulnitskiy B. A. , Kirichenko A. N.
Published: November 2020

This paper provides the first part of the study on the magnesium effect on the structural phase composition, physical and mechanical properties of nanostructured aluminum-magnesium composite materials with the composition AlxMgy + 0.3 wt.% C60 fullerene. Composite powders were obtained by the simultaneous mechanical activation of initial materials in a planetary ball mill in an argon atmosphere. It was found that the obtained powders have a complex hierarchical structure made up of 50–200 μm aggregates consisting of 5–10 μm strong high-density agglomerates, which in turn are a combination of nanoscale (30–60 nm) crystallites. It was found that the increase in magnesium concentration in the composite up to 18 wt.% makes it possible to obtain crystallites with an average size of less than 30 nm during mechanical activation, while the size of aggregates is less than 50 μm. The maximum solubility of magnesium in aluminum with a crystallite size of 30–70 nm during mechanical activation was 15 wt.% (17 at.%). Using the differential scanning calorimetry method, it was found that nanostructured composites undergo irreversible structural phase transformations during heat treatment in a temperature range of 250–400 °C: recrystallization, decomposition of the α-solid solution of magnesium in aluminum and formation of intermetallic β-(Al3Mg2), γ-(Al12Mg17) and carbide (Al4C3) phases. In addition, the Raman spectra contain peaks that, according to some sources, correspond to covalent compounds of aluminum with C60 fullerene – aluminum-fullerene complexes. The data obtained will be used in further research to determine parameters for the thermobaric treatment of nanocmposite powder mixtures in order to obtain and test bulk samples.
A High-Order HDG Method with Dubiner Basis for Elliptic Flow Problems
Authors: Bastidas Manuela , Lopez-Rodríguez Bibiana , Osorio Mauricio
Published: November 2020

We propose a standard hybridizable discontinuous Galerkin (HDG) method to solve a classic problem in fluids mechanics: Darcy’s law. This model describes the behavior of a fluid trough a porous medium and it is relevant to the flow patterns on the macro scale. Here we present the theoretical results of existence and uniqueness of the weak and discontinuous solution of the second order elliptic equation, as well as the predicted convergence order of the HDG method. We highlight the use and implementation of Dubiner polynomial basis functions that allow us to develop a general and efficient high order numerical approximation. We also show some numerical examples that validate the theoretical results.
Çok yönlü sıcak dövme işleminin Al-7Si-4Zn-3Cu alaşımının mekanik ve tribolojik özelliklerine etkisi
Authors: ALEMDAĞ Yasin , KARABIYIK Sadun , PÜRÇEK Gençağa
Published: November 2020

Bu çalışmada farklı çevrim sayılarında çok yönlü sıcak dövme işlemine
tabi tutulmuş Al-7Si-4Zn-3Cu alaşımının mekanik ve tribolojik özellikleri incelenmiştir.
Çok yönlü sıcak dövme işlemi alaşımın içyapısında bulunun silisyum parçalanmasına
ve dendritik yapının ortadan kalkmasına yol açmıştır. Bu işlem Al-7Si-4Zn-3Cu
alaşımının akma ve çekme dayanımı ile kopma uzaması değerlerini artırmış,
sertliğini ise düşürmüştür. En yüksek akma ve çekme dayanımı iki çevrim dövme
uygulanmış alaşımdan, en düşük sertlik ve en yüksek kopma uzaması üç evrim
uygulanmış alaşımdan elde edilmiştir. Diğer taraftan çok yönlü sıcak dövülmüş
alaşım homojenize edilmiş durumuna göre daha yüksek sürtünme katsayısı ve daha
düşük aşınma direnci sergilemiştir. Aşınma deneyi sonucunda alaşımların yüzeylerinde
sıvanmış tabakaların oluştuğu ve soyulmaların meydana geldiği görülmüştür. Ancak
sıvanmanın gerek homojenize edilmiş gerekse dövülmüş durumdaki numunelerde etken
aşınma mekanizması olduğu belirlenmiştir.
Hidrofobik çark yüzeylerinin santrifüj tip bir pompa performansına etkilerinin deneysel incelenmesi
Authors: ÖZBEY Mustafa , GÜRBÜZ Mevlüt , KARAKURT Uğur
Published: November 2020

Nüfusun ve
sanayileşmenin artmasına paralel olarak her geçen gün artan elektrik enerjisi ihtiyacı
mevcut enerjiyi daha verimli kullanmayı gerekli kılmaktadır. Bundan dolayı, bu
çalışmada santrifüj tip bir pompa çarkının mevcut tasarımı değiştirilmeden
ıslak yüzeyleri hidrofobik özellik kazandırılacak şekilde kaplanarak pompa
kapasitesi ve verimi üzerine etkileri deneysel olarak incelenmiştir. Çarkın
ıslak yüzeyleri floroidetilenpropilen (FEP), perfloroalkoksi (PFA) ve politetrafloretilen
(PTFE) olmak üzere 3 farklı karbon bazlı polimer malzeme ile kaplanmıştır. Kaplanan yüzeylerin temas açısı
sırasıyla 105o, 110o ve 95o ölçülerek hidrofobikliği
belirlenmiştir. Deneysel olarak pompa performans eğrileri elde edilerek hidrofobik
çark yüzeylerinin kaplamasız konvansiyonel çarka kıyasla pompa özgül hızını
yaklaşık %10 düşürdüğü, dolayısıyla kapasitesini %10, verimini ise sırasıyla
yaklaşık %5, %5,3 ve %4 artırdığı belirlenmiştir.
Panelist atama problemi için bir algoritma ve karar destek sistemi: TÜBİTAK örneği
Authors: KAT Bora
Published: November 2020

Proje önerilerinin sağlıklı bir şekilde ve proje konusunda uzmanlığa sahip kişiler tarafından değerlendirilmesi hem kaynakların etkin bir şekilde kullanılması hem de bu hizmetleri yürüten kurumların güvenilirliği açısından önem taşımaktadır. Bu çalışmada, birden fazla proje önerisinin değerlendirildiği panellerde en uygun panelist kümesinin oluşturulması için potansiyel panelist adaylarını dinamik bir şekilde listeleyen bir algoritma ve bu algoritmayı kullanan bir karar destek sistemi (PaneLIST) geliştirilmiştir. MS Excel VBA tabanlı PaneLIST, ülkemizde araştırma desteklerininin önemli bir bölümünü sağlayan ve bunu gerçekleştirirken her yıl çok sayıda panel düzenleyen TÜBİTAK’ın verileri kullanılarak oluşturulan test panellerinde sınanmış ve elde edilen sonuçların öngörülen kriterlerin tamamını önemli ölçüde sağladığı görülmüştür. Ayrıca, PaneLIST’in sunduğu çözümler, uygunluk skorları toplamını en büyükleyen (EBSkT) ve proje önerilerinin değerlendirme seviyeleri arasındaki sapmaları en küçükleyen (EKSp) tamsayılı programlama modelleri ile birlikte bu iki durumu bir arada ele alan üçüncü bir modelden (EBSkT-5) elde edilen kesin ve en iyi çözümleri ile kıyaslanmıştır. PaneLIST’in, yüksek uygunluk skorları toplamını, projeler arasında dengeli bir dağılım gözeterek gerçekleştirdiği ve bu yönüyle EBSkT ve EKSp’de yer alan iki hedefi bir arada gözettiği; %5’lik bir sapma kısıtı altında en büyük skoru bulmayı amaçlayan problem (EBSkT-5) ile hemen hemen aynı (%1’in altında yakınlık) performansı gösterdiği belirlenmiştir.
Değiştirilebilir konum süresine sahip takip cihazlarında kümeleme parametrelerinin tahmini ve anomali tespiti
Authors: DATLICA Mustafa , ÇAKIT Erman
Published: November 2020

Bu çalışmada, öncelikle takip cihazı ile konum ve zaman verileri toplanmış olup, takip edilen nesnelerin konum davranışlarındaki anomalileri tespit etmek amaçlanmıştır. Elde edilen veriler üzerinde ST-DBSCAN (Spatial-Temporal Density-Based Spatial Clustering of Applications with Noise) yoğunluk bazlı kümeleme algoritması uygulanarak takip edilen nesneye ait, hangi zaman aralıklarında nerede olduğuna dair haftalık örüntüler tespit edilmiştir. ST-DBSCAN algoritmasının girdi parametreleri, takip cihazından gelen verinin sıklığı ve toplam veri paketi sayısına göre değişiklik göstermektedir. Bu kapsamda ST-DBSCAN algoritmasında kullanılan parametreler ile veri gönderme sıklığı ve veri paketi sayısı, takip edilen nesnenin davranışlarına göre etiketlenmiştir. Etiketlenen bu veriler üzerinde doğrusal regresyon ve yapay sinir ağları yöntemleri karşılaştırılmış, kümeleme parametrelerinin tahminini yapabilecek bir model önerilmiştir. Haftalık örüntüler, takip edilen nesneye ait bilgiler kullanılarak geliştirilen yöntemler ile tespit edilmiş ve bu örüntüler takip edilen nesneye ait normal davranışlar olarak kabul edilmiştir. Anlık konumu elde edilen veri örüntüye aykırı ise anomali olarak tanımlanmıştır.
Teknik kısıtlı 1,5 boyutlu kesme problemi için karma tamsayılı matematiksel modeller
Authors: SARAÇ Tuğba , SAĞIR ÖZDEMİR Müjgan
Published: November 2020

Kesme problemlerinin çözümünde genellikle önce kesme planları türetilip daha sonra bir matematiksel model yardımıyla hangi kesme planlarının kullanılacağı belirlenmektedir. Öte yandan tüm kesme planlarını türetmenin güçlüğü ve kesme planı sayısının genellikle çok fazla olması bu konuda karşılaşılan en temel problemlerdir. Bu çalışmada parça çeşidi ve şerit sayısı kısıtlı 1.5 boyutlu kesme problemi için kesme planlarını da türeten bütünleşik bir matematiksel model geliştirilmiştir. Doğrusal olmayan bu model, çözüm güçlüğünü ortadan kaldırmak üzere doğrusallaştırılmıştır. Rassal olarak türetilen test problemleri kullanılarak, önerilen her iki modelle elde edilen sonuçlar, kesme planlarının önceden türetildiği klasik modelle karşılaştırılmıştır. Elde edilen sonuçlar, kesme planlarını da kendisi türeten doğrusal modelin belirli büyüklüğe kadar makul sürede çözülebildiğini göstermiştir. Özellikle, problem için geliştirilen matematiksel modelin doğrusal yapıya kavuşturulmasının, literatür için önemli bir kazanım olacağı düşünülmektedir.
Meta sezgisel yöntemlerle çok seviyeli görüntü eşikleme
Authors: ÖLMEZ Yağmur , SENGUR Abdulkadir , OZMEN KOCA Gonca
Published: November 2020

Çok seviyeli eşikleme, en çok kullanılan görüntü bölütleme yöntemlerinden birisidir. Görüntü bölütleme de kullanılan pek çok metot hesaplama karmaşıklığından dolayı çok fazla zaman tüketmektedir. Ayrıca eşik seviye sayısı arttıkça uygulama daha karmaşık ve zaman alıcı hale gelmektedir. Bu çalışmada, hesaplama zamanını azaltmak ve çok seviyeli eşikleme performansını geliştirmek için PSO yönteminin hızlı yakınsama oranı dikkate alınarak 2 boyutlu yerel olmayan histograma dayalı çok seviyeli bir eşikleme yöntemi (2DYOH-PSO) önerilmiştir. Önerilen 2DYOH-PSO yöntemi iki boyutlu Renyi’nin entropisine dayalı eşikleme yöntemi kullanılarak gerçekleştirilmiştir. Deneysel çalışmalar, Berkeley-Benchmark veri setindeki 300 görüntü için farklı seviyeli eşik değerleri dikkate alınarak yapılmıştır. Var olan 5 farklı eşik belirleme yöntemi (Diferansiyel Gelişim, Yapay Arı Algoritması, Yer Çekimi Arma Algoritması, Kbest Yer Çekimi Arma Algoritması, Kaotik Kbest Yer Çekimi Arma Algoritması) ile karşılaştırılarak, önerilen 2DYOH-PSO yönteminin performansı değerlendirilmiştir. 2DYOH-PSO yönteminin başarımı 12 farklı performans değerlendirme endeksi kullanılarak belirlenmiştir. 2DYOH-PSO ile 3 seviyeli eşikleme işlemi gerçekleştirildiği durumda, mevcut 5 farklı yöntem ile 12 performans değerlendirme indeksi bakımından yapılan bölütleme işlemlerinin başarımları BDE’de %2,63 oranında, PRI’de % 0,83 oranında SSIM’de % 15,5 oranında, RMSE’de %13,2 oranında, PSNR’de %8,63, CC’de % 35 oranında, AD’de % 13,9 oranında, MD’de 14,75 oranında, NAE %10 oranında iyileşme sağlanmıştır. 2DYOH-PSO ile 5 seviyeli eşikleme işlemi gerçekleştirildiği durumda ise Berkeley-Benchmark veri setindeki görüntülerin bölütlenmesinde ki başarımın BDE’de %1, VOI’ de %1,4, SSIM’ de %1,3, FSIM’ de %0,66, RMSE’ de%0,46, PSNR’ de %0,46, CC’ de %21,69, AD’ de %0,84 oranında iyileştiği deneysel sonuçlar ile gösterilmiştir.
Geschwindigkeitssprünge an Vorschubachsen
Authors: Schulte Alexander , Lechler Armin , Verl Alexander
Published: November 2020

In diesem Artikel wird ein hybrider Ansatz mit Aktor vorgestellt, der die Impulsübertragung bei mechanischen Stößen ausnutzt, um eine Vorschubachse sprungartig zu beschleunigen. Der Maschinentisch wird hierfür mit einem Aktor ausgestattet, der eine Impulsmasse relativ zum Tisch bewegt und zum geforderten Zeitpunkt definiert auf eine vorgesehene Stoßfläche schlägt. DasErgebnis ist, dass mit diesem Konzept beispielsweise Ecken einer Kontur mit annähernd konstanter Bahngeschwindigkeit durchfahren werden können, da nahezu keine Beschleunigungs- und Bremswege notwendig sind. Experimentelle Untersuchungenerfolgen an einem einachsigen Versuchsstand, zusätzlich dazu wurde ein Simulationsmodell entwickelt, mit dem das Potenzial für einen mehrachsigen Betrieb abgeschätzt werden kann.
O IMPACTO DAS ÁREAS DEGRADADAS NA DISTRIBUIÇÃO ESPACIAL DO ZIKA VÍRUS: UM ESTUDO DE CASO
Authors: Rodrigues Diego Freitas , Barcellos Pedro Henrique , Da Silva Leticia Maria
Published: November 2020

O Zika vírus é um arbovírus que tem como vetor principal o mosquito Aedes aegypti e a doença tem ganhado importância devido à ampla disseminação em território nacional, incluindo o estado de Alagoas. O presente trabalho levanta a hipótese de que uma maior proporção de áreas degradadas no perímetro urbano contribui diretamente para o aumento no número de caso de pessoas infectadas pelo mosquito Aedes Aegypti. Com base nos casos notificados de Zika vírus no ano de 2016, foi empregada uma metodologia de pesquisa mista para identificar espacialmente e mensurar a incidência de casos de arboviroses em municípios selecionados, verificando se há correlação estatística-espacial entre a concentração das arboviroses notificadas e as áreas degradadas mapeadas por este estudo. Para quantificar as áreas degradadas desses dois municípios, foram utilizadas imagens de satélite obtidas pelo software livre Google Earth Pro. Também foi utilizada estatística descritiva para apresentar indicadores de saúde ambiental como a taxa de esgotamento sanitário, abastecimento de água e coleta de lixo, sendo esses dados provenientes de fontes secundárias. Os resultados apontam uma associação direta entre a distribuição de casos notificados de arboviroses e a maior concentração de áreas degradadas nos municípios avaliados.