bluuebunny/crossref_metadata_2025 huggingface dataset:
المعرفة الضمنية واستثمارها في تطوير إجراءات تأمين المنشآت الأمنية
Authors: سعود العقيد د. بدر بن سعود آل , القرني د. عبد الرحمن بن عبيد
Published: June 2019

ملخص:

الاهتمام بالمعرفة وإدارتها يؤثر بدرجة كبيرة في تطوير مجالات كثيرة من بينها المجالات الأمنية التي تقوم على المعلومات والخـــــــبرات في أعمالها، وتحاول هـــــــــذه الدراسة معرفة أسباب نجاح العمليات الإرهابية السابقة وكيفية تفعـيــــل دور المعرفة الضمنية، من خلال استثمارها، في تطوير إجراءات تأمين المنشآت الأمنية ومن ثم تحييد احتمالات نجاح هذه العمليات الارهابية، وقد تم تطبيق الدراسة على مجموعة من منسوبي قوات الأمن الخاصة ومنسوبي قوات الطوارئ الخاصة المسؤولين عن تأمين المنشآت الأمنية في منطقتي الرياض ومكة المكرمة، واستخدمت الدراسة المنهج الوصفــــــــي المسحي، واعتمــــــدت على الاستبــــــــــانة في جمعهـــا للبيانات، وخلصت الى مجموعة من التوصيات من ابرزها: ضرورة وضع استراتيجية لاستثمار المعرفة الضمنية لدى الخبراء العاملين في تأمين المنشآت الأمنية بهدف تطوير الإجراءات والخطط الكفيلة بتأمين تلك المنشآت، على أن تتضمن هذه الاستراتيجية كتابة تقارير وافية وكافية عن الاعتداءات والعمليات الإرهابية التي تتعرض لها المنشآت الأمنية على مستوى المملكة، وتهيئة أرشيف إلكتروني من خلال تحويل جميع الخبرات والمعارف الضمنية عند رجال الأمن الذين تعاملوا بشكل مباشر مع هذه الحوادث إلى معرفة صريحة مدونة وبما يسهل الرجوع اليها والاستفادة منها عند الحاجة، والاستفادة من المعرفة الضمنية عند أصحاب الخبرة الكبيرة في مجال تأمين المنشات الأمنية وتدوين تجاربهم قبل مغادرتهم العمل بالتقاعد أو غيره ، والعمل على انشاء جماعة مهنية تهتم بتبادل التجارب والخبرات بين منسوبي الأجهزة المسؤولة عن تأمين هذه المنشآت وبحيث تأخذ في بدايتها شكلاً محلياً على أن يقبل التمدد إقليمياً ودولياً في المستقبل، وتضمين نظام الخدمة العسكرية ما ينص على أن الخبرة أو المعرفة الضمنية عند رجل الأمن عهدة يسلمها العسكري بمجرد تقاعده أو تركه العمل أو المهمة المكلف بها من خلال تحويلها إلى معرفة صريحة مكتوبة.
Big data investment and knowledge integration in academic libraries
Authors: Manaseer Saher , Alawneh Afnan R. , Asoudi Dua
Published: June 2019

Recently, big data investment has become important for organizations, especially with the fast growth of data following the huge expansion in the usage of social media applications, and websites. Many organizations depend on extracting and reaching the needed reports and statistics. As the investments on big data and its storage have become major challenges for organizations, many technologies and methods have been developed to tackle those challenges.

One of such technologies is Hadoop, a framework that is used to divide big data into packages and distribute those packages through nodes to be processed, consuming less cost than the traditional storage and processing methods. Moreover, it allows an organization to store all its data, unlike the traditional methods of selecting and discarding some data.

In this study, researchers investigate the investment of Hadoop in managing the academic libraries’ big data, focusing on three Vs (velocity, variety, and volume).

The studied population is academic libraries in Jordanian universities, and the results show how Hadoop framework using the map/reduce technique can be used to manage the big data of such libraries.
تطبيقات الهواتف الذكية والأجهزة المحمولة في مراكز الوثائق والأرشيف: دراسة تحليلية
Authors: الصاوي د.السيد صلاح
Published: June 2019

ملخص:

استحدثت مراكز الوثائق والأرشيف تطبيقات للهواتف الذكية والأجهزة المحمولة لمساعدتها في أنشطتها والخدمات التي تقدمها للمستفيدين. تستكشف هذه الدراسة تطبيقات الهواتف الذكية المتعلقة بمراكز الوثائق والأرشيف، وأسباب استخدامها، وأهميتها في تعزيز الخدمات المقدمة للمستفيدين، وسماتها (مسمى التطبيق، أهداف التطبيق، عدد التطبيقات لكل أرشيف، اللغات المتوفر بها التطبيق، منصة التشغيل،...)، والتحديات التي واجهت مراكز الوثائق والأرشيف في تطوير تطبيقات للهواتف الذكية. شملت الدراسة تطبيقات الهواتف الذكية والأجهزة المحمولة في ثلاثة أرشيفات وطنية: الولايات المتحدة، والمملكة المتحدة، والإمارات العربية المتحدة. واستخدمت الدراسة منهج المسح الوصفي، واستعانت بقائمة نقاط مقترحة لتحليل سمات هذه التطبيقات. وكشفت الدراسة عن إنشاء الأرشيفات لـسبعة عشر (17) تطبيقاً للهواتف الذكية والأجهزة المحمولة، وشكلت التطبيقات ذات التغطية الموضوعية السياسية أكثر من نصف التطبيقات التي أنشأتها الأرشيفات الوطنية بنسبة 53%، تلتها التطبيقات ذات التغطية التاريخية بنسبة 17.5%، أما النسبة المتبقية 29.5% فشكلت تطبيقات لموضوعات متميزة؛ مثل المال قديما، الأنساب، أرشيفات الويب للمؤسسات الحكومية. وتُختتم الدراسة بمقترحات لمراكز الوثائق والأرشيف العربية التي تخطط لتطوير تطبيقات ناجحة للهواتف الذكية والأجهزة المحمولة.
The “other side” of whistleblowing practice: Experiences from Nigeria
Authors: Ifejika Solomon I.
Published: June 2019

Whistleblowing, the act of reporting or disclosing wrongdoing, is widely proven to have a practically useful mechanism in fighting corruption in public and private sectors. Within the ambit of the whistleblowing framework, the disclosure of corrupt practices is primarily justifiable only on the ground that the action is genuinely directed towards protecting the interest of the public. The usual benefit of financial reward to whistleblowers is secondary, as it basically aims at encouraging individual employees to expose unethical misconducts in their organizations. Regardless of this, whistleblowing intrinsically benefits the public as well as the individual(s) who raises the alarm against any dishonest acts. However, despite its benefits to the public and the individual informant, whistleblowing attracts certain heavy costs, mainly on the part of the whistleblower, mostly in the form of victimization or witch hunting, retaliation, denial of work-related benefits, recrimination, suspension from work and even dismissal, for their involvement in disclosure wrongdoing. Impliedly, besides its valuable attributes as an important anti-corruption weapon and mechanism for incentivizing the citizens, there is the “other side” of the whistleblowing practice. Using some practical examples and experiences from Nigeria, this paper demonstrates that there is the “other side” of whistleblowing, and concludes that the practice, indeed, has distinct dual sides, especially in the absence of a well-articulated legal framework for protection of whistleblowers, as in the case of Nigeria. Thus, in this paper, we basically argue that the Nigerian government should take immediate actions to enact a comprehensive whistleblowers' protection law, so as to guarantee adequate protection of informants, who risk their lives to expose corruption acts in the interest of the public, from likely abuses. As this study is a qualitative and theoretical research, we adopt the documentary methods of data collection and analysis. These approaches were preferred as they will allow for the objective interrogation of the subject matter under consideration and the achievement of the study's objective.
Emergent planning for South Africa's blue economy: Evidence from coastal and marine tourism
Authors: Rogerson Christian M. , Rogerson Jayne M.
Published: June 2019

Ocean-based industries are in focus in terms of expanding debates and planning around the blue economy. Against this backdrop the objective in this paper is to examine contemporary directions in South Africa concerning planning for the blue economy as a whole and more specifically for the sector of coastal and marine tourism. Using documentary analysis of official planning and strategic documents, South Africa’s blue economy strategy, which is titled ‘Operation Phakisa’, is unpacked and critiqued. Attention shifts to examine current directions and challenges of unfolding planning for the expanded development of coastal and marine tourism in South Africa. It is shown that uneven spatial development characterises the existing coastal tourism economy. Arguably, tourism planning is linked to Operation Phakisa which is being challenged for a number of shortcomings, most importantly for prioritising investment attraction and economic growth stimulation over issues about the conservation of maritime resources.
Business incubators and green technology: The Gauteng Climate Innovation Centre, South Africa
Authors: Gonsalves Maruschka , Rogerson Jayne M.
Published: June 2019

Business incubators are a vehicle to assist the survival prospects of start-up enterprises, many of which fail in their early years of operation. One special form of business incubator is the Climate Innovation Centre (CIC) which is part of international debates around green economies and appropriate technologies for climatecompatible development. CICs are an intervention to build innovation sites to ameliorate climate change and a highly distinctive form of business incubator in which the explicit focus is upon supporting small business startups allied to the application of green technologies. Using a qualitative approach the article analyses the establishment and operations of the Gauteng Climate Innovation Centre in South Africa. The CICSA in its first five years of operations has been ‘learning through experience’ and introduced a number of changes since its launch in 2012, including an extension of the business incubation programme and an adjusted focus to South Africa’s climate change related ‘green’ issues around energy, water and waste. Although 5 years is too short for a conclusive evaluation of CIC operations the evidence from this research with South African clean-tech enterprises is largely positive and suggests that the assistance provided by the CIC has contributed towards enterprise development.
USE OF THERMAL IMAGING IN CONSTRUCTION
Authors: Proszak-Miąsik Danuta
Published: June 2019

Thermovision is a research method based on non-invasive and non-contact evaluation of temperature distribution on the surface of the examined body. These methods are based on observation and recording of the distribution of infrared radiation, sent by each body whose temperature is higher than absolute zero (-273C) and visualization of the temperature field by thermal imaging equipment. In construction, thermovision is used to assess the quality of materials used in construction, structural solutions and the quality of construction work. With its help we can locate, for example, thermal bridges, which are the result of improperly made or damaged during the operation or installation of thermal insulation. Detection of thermal bridges helps to reduce the amount of fuel used and thus save on the costs of heat energy. Using thermal imaging it is also possible to assess the condition of heating pipelines (damage to insulation, corrosion, location of leaks), control heating devices such as: heat substations, radiators. The subject of the study is to show examples of how thermal imaging is used and useful in construction.
MODELING OF PROCESSES IN CRUDE OIL TREATED WITH LOW-FREQUENCY SOUNDS
Authors: Blinayeva Yelena , Smailova Saule
Published: June 2019

These days new methods of purification of crude oil from paraffin are being sought to improve the quality of oil, reduce its cost and optimize the processes of technological preparation of oil. The paper describes the method of conducting an experiment to study the impact of low-frequency sounds on oil samples of the Zhanazhol field, and presents the results of experiments, the input parameters of the experiment (exposure time and frequency of infrasound), at which the maximum reduction of the kinematic viscosity of oil is achieved. Further study of processes in crude oil under the influence of low-frequency sounds is planned to be investigated in Comsol Multiphysics®.
GENERATORS OF ONE-TIME TWO-FACTOR AUTHENTICATION PASSWORDS
Authors: Ussatova Olga , Nyssanbayeva Saule
Published: June 2019

The paper presents algorithms for generating a one-time two-factor authentication passwords where application of trigonometric functions have been considered. To protect the opening of a one-time password, a secret string is read that consists of a sequence of randomly generated characters. The second factor is due to the fact that that the code has a certain validity period. The presented password generators allow the formation of secret words and trigonometric functions that the proposed two-factor authentication method consists of. The algorithm presented was implemented in Java Script. The algorithm includes blocks for checking randomly generated words and functions.
The Significance of ‘Things’ in Cybercrime: How to Apply Actor-network Theory in (Cyber)criminological Research and Why it Matters
Authors: Van der Wagen Wytske
Published: June 2019

In recent years computer technologies and digital devices have become ubiquitous in all facets of human existence, including crime and deviant behavior. Various forms of criminality have emerged in which technical entities play a substantial role. It can be argued that such a development urges criminologists and anthropologists to draw more attention to the significance of things in crime. Latour’s (2005) actor-network theory (ANT), which considers non-human entities as active participants of the social, could be a useful approach for extending our analytical focus to the non-human. The article will not only asses why, but also how we can apply ANT as a more-than-human methodology in qualitative research, by discussing three ANT-based methodological principles: ‘follow the tool’, ‘follow the hybrid’ and ‘follow the network.’ In this scope, this article draws on earlier conducted qualitative ANT case studies on different forms of high-tech cybercrime. In a more general vein, the article aims to show that innovations in qualitative research methods can be also informed by theory.
Percepciones de estudiantes universitarios chilenos sobre uso de redes sociales y trabajo colaborativo
Authors: Cabero Almenara Julio , Del Prete Annachiara , Arancibia Muñoz Maria Luisa
Published: June 2019

En los últimos años hemos sido testigo de un uso, siempre más difundido, de las redes sociales digitales (RSD), con fines educativos. El alumnado declara hacer un uso didáctico de las redes y sus herramientas y, al mismo tiempo, reconoce el trabajo colaborativo como una metodología que promueve su aprendizaje y que viene propiciada por el uso de las redes sociales. Entre los propósitos del siguiente estudio, se encuentra indagar las percepciones que el alumnado tiene respecto al uso de las redes sociales como herramienta educativa y conocer sus preferencias con respecto al trabajo colaborativo. La investigación realizada se encuadra dentro de las denominadas ex post facto, no experimental y descriptiva. La muestra de la investigación estuvo formada por 460 estudiantes de diferentes carreras del área de ingeniería de una institución de educación superior chilena, durante el curso académico 2017-18. Entre los resultados destacables, podemos afirmar que Internet se está presentando como una de las tecnologías que va penetrando con más fuerza en las Universidades, y que los alumnos la suelen utilizar constantemente para fines educativos. Es por estas razones que consideramos que existen las condiciones iniciales para la incorporación de las redes sociales a la enseñanza formal. Además, nuestros resultados muestran que el interés de trabajar con otros estudiantes determina la actitud del alumnado hacia el trabajo colaborativo. Ello nos lleva a reclamar la necesidad de que el docente se asegure de las percepciones que tienen los alumnos, y aplique estrategias específicas.
Estrategias comunicativas y tareas de interacción oral en L3 presenciales y en línea
Authors: Keim Cubas Lucrecia , Delgar Farrés Gemma
Published: June 2019

Durante la realización de tareas orales de aula, tanto presenciales como en línea, los aprendientes se enfrentan a importantes retos comunicativos que les llevan a actuar de forma estratégica. En el presente artículo se compara el uso de estrategias comunicativas mientras dos parejas de estudiantes de francés y dos de alemán como lenguas adicionales realizan ocho tareas orales de forma presencial y en línea mediante videoconferencia a fin de estudiar la posible incidencia de la modalidad, la tipología de tarea y la lengua sobre el uso de estrategias comunicativas. Las tareas de tipo jigsaw y ranking se grabaron y transcribieron con el programa CLAN y el enfoque metodológico aplicado ha sido cualitativo. En nuestros datos, la tarea de tipo jigsaw suscitó  sobre todo el uso de estrategias comunicativas relacionadas con procesos de clarificación, mientras que la tarea de tipo ranking favoreció las estrategias relacionadas con la reelaboración del discurso. Por otro lado, hay ligeras diferencias entre el alumnado de francés y el de alemán en el momento de activar estrategias compensatorias (búsqueda, petición de ayuda, cambio de código). En todos los casos las estrategias se activan de manera articulada tejiendo secuencias interactivas complejas. Así pues, los resultados de nuestro estudio apuntan a que, con excepción de la gestualidad icónica al activar la estrategia mímica, la modalidad no influye de forma destacable sobre el uso de estrategias. Sin embargo, tanto la tipología de tarea como la lengua de aprendizaje parecen haber tenido efecto sobre las estrategias activadas.
Experiencia del aula invertida para promover estudiantes prosumidores del nivel superior
Authors: González Fernández María Obdulia , Huerta Gaytán Pablo
Published: June 2019

Este trabajo describe una experiencia académica del aula invertida implementada como estrategia en la asignatura de Promoción, impartida a estudiantes del segundo semestre de Ingeniería en Computación, de la Universidad de Guadalajara. El propósito principal fue promover el consumo y producción de recursos educativos. Se planeó la aplicación de una estrategia didáctica dividida en tres momentos: aula invertida con recursos propuestos por el profesor de acuerdo con el estilo de aprendizaje del estudiante; la creación de recursos didácticos por parte del alumnado; y finalmente, la evaluación a partir de un estudio descriptivo a una muestra de 24 sujetos. Durante el estudio se aplicó inicialmente un cuestionario tipo Likert organizado en torno a la percepción metodológica referida al aprendizaje, a la interacción docente-estudiante, estudiante-estudiante, ritmos de aprendizaje, colaboración, resolución de problemas, motivación y actitud prosumidora. Los resultados destacan que el 88% están de acuerdo en la metodología y personalización de ritmos de aprendizaje; un 92% afirma que la estrategia permitió mejorar su aprendizaje y habilidades de comunicación; por lo anterior se deduce una mayor interacción entre ellos y el profesor, lo que desarrolló su pensamiento crítico y habilidades para resolver problemas; se pudieron integrar estrategias para la creación y difusión de contenidos; se aumentó la motivación del alumno para colaborar y comprobar el principio constructivista de aprender haciendo. La aplicación de modelos didácticos activos requiere la conformación de ambientes de aprendizajes bajo principios del estilo del aprendiz e integrar sus intereses para el desarrollo de sus competencias.
Evaluación de proceso de un programa universitario de inglés mediante Blended Learning
Authors: Martinic Lenta Rodolfo , Urzúa Martínez Sergio , Úbeda Menichetti Ricardo , Aranda Gengler Roxana
Published: June 2019

En el contexto de globalización actual, las universidades deben enfrentar exigencias de internacionalización que implican proveer a los estudiantes una formación integral orientada al desarrollo de competencias profesionales, entre las cuales el dominio de una segunda lengua ocupa un lugar central. En este marco, durante los últimos años la Universidad de Santiago de Chile, ha implementado un programa de inglés Blended Learning en 48 carreras de ocho facultades, cuyo objetivo consiste en desarrollar competencias lingüísticas y comunicativas a un nivel intermedio. Para esto, el programa cuenta con tres componentes pedagógicos: clases presenciales, tutorías académicas y una plataforma on-line. A fines del año 2017 y comienzos del año 2018, se realizó una evaluación de proceso que buscó conocer, a partir de la perspectiva de los distintos actores involucrados, cómo se ha implementado el programa, poniendo énfasis en el avance hacia el cumplimiento de sus objetivos. La información fue recolectada a través de tres técnicas: una encuesta sobre la experiencia de aprendizaje aplicada a los estudiantes (N=780), un grupo focal con los docentes del programa y entrevistas semiestructuradas con coordinadores o jefaturas de carrera de la Universidad. Los resultados dan cuenta de una evaluación positiva del programa cuando se observa cada componente en su propio mérito. Sin embargo, al analizar la integración entre estos se constataron cuatro tensiones asociadas a: la orientación para el trabajo autónomo, la regulación en la distribución de tutorías, la transición de los contenidos pedagógicos desde la plataforma a la clase y la diferenciación funcional entre los distintos componentes.
Metasíntesis cualitativa sobre colaboración científica e identidad digital académica en redes sociales
Authors: Salinas Ibáñez Jesús , Marín Juarros Victoria Irene
Published: June 2019

La colaboración científica y la gestión de la identidad académica tienen un papel importante en la productividad académica, como algunos estudios ya han mostrado. Con la aparición de las herramientas de redes sociales, esas posibilidades se han ampliado y la presencialidad en la actividad académica no es siempre necesaria. Algunos trabajos han abordado estos temas, pero todavía no existe una sistematización de la literatura que ayude a identificar posibles líneas de trabajo en este campo  y muestre las ventajas y desventajas de modos alternativos de colaboración y desarrollo de la identidad académica en línea. Este estudio pretende cubrir ese vacío mediante una metasíntesis cualitativa de estudios centrados en el uso de las herramientas de redes sociales generalistas (de temática no específica) y académicas con propósitos de colaboración científica y cuidado de la identidad digital académica por parte de investigadores académicos. Las búsquedas se realizaron en cinco bases de datos internacionales relevantes en el campo de la educación. Además, se incorporaron algunas referencias bibliográficas de estudios principales. Este proceso llevó a la identificación final de 68 estudios entre 2008 y 2018, cuyos hallazgos se sintetizan en los resultados a través de una división por categorías. A modo de conclusión, se denota la falta de estudios con una visión crítica y de análisis profundo de las prácticas académicas en las herramientas de redes sociales y se discuten los resultados junto a líneas de investigación futuras respecto a las dimensiones identificadas: el networking, el intercambio de conocimiento y la identidad digital.
Determinación del uso problemático de las redes sociales por estudiantes universitarios
Authors: Marín-Díaz Verónica , Vega-Gea Esther , Passey Don
Published: June 2019

Las Tecnologías de la Información y la Comunicación (TIC) en general, y el Internet en particular, están presenten diariamente en nuestras vidas. Es un hecho que vivimos en una sociedad digital, y por tanto, las nuevas generaciones pertenecen ya a lo que se ha denominado “nativos digitales”, ya que es el mundo en el que se desenvuelven continuamente. Ello ha provocado que comience a hablarse de uso problemático o abuso de determinadas herramientas que ofrecen las TIC, como es el caso de las Redes Sociales. El presente estudio tiene como propósito general realizar un análisis del uso de las redes sociales en  estudiantes universitarios del Grado de Magisterio de Educación Infantil y Primaria de la Universidad de Córdoba. Para la recogida de la información se empleó una versión adaptada del Internet Adiction Test. Los resultados han indicado que el alumnado no percibe tener una conducta nociva ni con Internet ni con las redes sociales en particular. Un dato a resaltar es que las chicas han manifestado un uso más problemático de las redes sociales que los chicos. En conclusión, podemos indicar que los maestros en formación no presentan un uso problemático de las redes sociales. No obstante, consideramos que hay que tomar se considera que se debería tomar esta conclusión con cautela y seguir analizando el uso que se hace de las TIC.
Estudiantes en contextos de educación a distancia. Variables vinculadas con el logro académico
Authors: Chiecher Analía Claudia
Published: June 2019

El artículo toma como punto de partida las altas cifras de abandono que caracterizan a la educación a distancia y, por el contrario, los bajos porcentajes de estudiantes que consiguen cursar trayectorias ajustadas a los tiempos que establece el plan de estudios. El objetivo del escrito se orienta a analizar perfiles de un grupo de estudiantes de primer año, de modalidad a distancia, cuyas trayectorias se ciñeron a la progresión temporal fijada por el plan de estudios. Se realizó un estudio no experimental y descriptivo en el cual participaron estudiantes de primer año de carreras de grado dictadas a distancia, quienes cumplían, además, la condición de haber regularizado todas las asignaturas previstas en el plan de estudios. Para la recolección de datos se administró un cuestionario de autoinforme, que recaba información sobre variables personales y contextuales con posible incidencia en las trayectorias académicas. Los resultados muestran que, entre las variables personales consideradas en el estudio, aquellas que parecen tener vinculación con trayectorias de logro son el nivel educativo de los padres, las metas de aprendizaje y las atribuciones causales internas y modificables. Asimismo, las variables contextuales percibidas como promotoras del logro se vincularon principalmente con la disponibilidad del profesor y su rapidez para responder consultas y ofrecer devoluciones de las actividades realizadas. La discusión propone líneas de acción que, sustentadas en los resultados del estudio, podrían contribuir a la promoción del logro estudiantil en la educación a distancia.
Ender Grønlands økonomi og erhvervsudvikling i fisk?
Authors: Bianco Nauja
Published: June 2019

What dilemmas and challenges are Greenland facing in the light of the wish for future independence? This article reflects on central issues relating to the Greenlandic economy and business structure of today and the possibilities in a future secession from the Kingdom of Denmark. The article demonstrates that – besides the grants from Denmark and the EU which amounts to approximately 60 % of the income of the Greenland Government – the foundation for Greenland’s economy and business structure since the 1950s and 60s has been fishery which is still thriving. The article also shows that this is a single stranded and sensitive business structure that cannot alone meet the income needs for an independent Greenland. The article points out that the Greenlandic economy needs diversification and that the business environment should be developed. Particularly innovation and new product development in the marine industry, such as development in bio-economy, could be elaborated. There is also room for entrepreneurship within the cultural and creative industries. Developments of the tourism industry must be pursued and a comprehensive strategy for attracting foreign and direct investment to Greenland should be developed.
Dissecting the sharp response of a canonical developmental enhancer reveals multiple sources of cooperativity
Authors: Park Jeehae , Estrada Javier , Johnson Gemma , Vincent Ben J , Ricci-Tam Chiara , Bragdon Meghan DJ , Shulgina Yekaterina , Cha Anna , Wunderlich Zeba , Gunawardena Jeremy , DePace Angela H
Published: June 2019

Developmental enhancers integrate graded concentrations of transcription factors (TFs) to create sharp gene expression boundaries. Here we examine the hunchback P2 (HbP2) enhancer which drives a sharp expression pattern in the Drosophila blastoderm embryo in response to the transcriptional activator Bicoid (Bcd). We systematically interrogate cis and trans factors that influence the shape and position of expression driven by HbP2, and find that the prevailing model, based on pairwise cooperative binding of Bcd to HbP2 is not adequate. We demonstrate that other proteins, such as pioneer factors, Mediator and histone modifiers influence the shape and position of the HbP2 expression pattern. Comparing our results to theory reveals how higher-order cooperativity and energy expenditure impact boundary location and sharpness. Our results emphasize that the bacterial view of transcription regulation, where pairwise interactions between regulatory proteins dominate, must be reexamined in animals, where multiple molecular mechanisms collaborate to shape the gene regulatory function.
Description and classification of bivalve mollusks hemocytes: a computational approach
Authors: Karetin Yuriy A. , Kalitnik Aleksandra A. , Safonova Alina E. , Cicinskas Eduardas
Published: June 2019

The fractal formalism in combination with linear image analysis enables statistically significant description and classification of “irregular” (in terms of Euclidean geometry) shapes, such as, outlines ofin vitroflattened cells. We developed an optimal model for classifying bivalveSpisula sachalinensisandCallista brevisiphonataimmune cells, based on evaluating their linear and non-linear morphological features: size characteristics (area, perimeter), various parameters of cell bounding circle, convex hull, cell symmetry, roundness, and a number of fractal dimensions and lacunarities evaluating the spatial complexity of cells. Proposed classification model is based on Ward’s clustering method, loaded with highest multimodality index factors. This classification scheme groups cells into three morphological types, which can be distinguished both visually and by several linear and quasi-fractal parameters.
Isolation and functional characterization of two dioxygenasese putatively involved in bixin biosynthesis in annatto (Bixa orellana L.)
Authors: Carballo-Uicab Victor Manuel , Cárdenas-Conejo Yair , Vallejo-Cardona Alba Adriana , Aguilar-Espinosa Margarita , Rodríguez-Campos Jacobo , Serrano-Posada Hugo , Narváez-Zapata José Alberto , Vázquez-Flota Felipe , Rivera-Madrid Renata
Published: June 2019

Carotenoid cleavage dioxygenases (CCDs) are enzymes that have been implicated in the biosynthesis of a wide diversity of secondary metabolites with important economic value, including bixin. Bixin is the second most used pigment in the world’s food industry worldwide, and its main source is the aril of achiote (Bixa orellana L.) seeds. A recent transcriptome analysis of B. orellana identified a new set of eight CCD members (BoCCD4s and BoCCD1s) potentially involved in bixin synthesis. We used several approaches in order to discriminate the best candidates with CCDs genes. A reverse transcription-PCR (RT-qPCR) expression analysis was carried out in five developmental stages of two accessions of B. orellana seeds with different bixin contents: (P13W, low bixin producer and N4P, high bixin producer). The results showed that three BoCCDs (BoCCD4-1, BoCCD4-3, and BoCCD1-1) had an expression pattern consistent with bixin accumulation during seed development. Additionally, an alignment of the CCD enzyme family and homology models of proteins were generated to verify whether the newly proposed CCD enzymes were bona fide CCDs. The study confirmed that these three enzymes were well-preserved and belonged to the CCD family. In a second selection round, the three CCD genes were analyzed by in situ RT-qPCR in seed tissue. Results indicated that BoCCD4-3 and BoCCD1-1 exhibited tissue-specific expressions in the seed aril. To test whether the two selected CCDs had enzymatic activity, they were expressed in Escherichia coli; activity was determined by identifying their products in the crude extract using UHPLC-ESI-QTOF-MS/MS. The cleavage product (bixin aldehyde) was also analyzed by Fourier transform infrared. The results indicated that both BoCCD4-3 and BoCCD1-1 cleave lycopene in vitro at 5,6-5′,6′.
Metabolomic and biochemical characterization of a new model of the transition of acute kidney injury to chronic kidney disease induced by folic acid
Authors: Perales-Quintana Marlene Marisol , Saucedo Alma L. , Lucio-Gutiérrez Juan Ricardo , Waksman Noemí , Alarcon-Galvan Gabriela , Govea-Torres Gustavo , Sanchez-Martinez Concepcion , Pérez-Rodríguez Edelmiro , Guzman-de la Garza Francisco J. , Cordero-Pérez Paula
Published: June 2019

Background

Renal diseases represent a major public health problem. The demonstration that maladaptive repair of acute kidney injury (AKI) can lead to the development of chronic kidney disease (CKD) and end-stage renal disease has generated interest in studying the pathophysiological pathways involved. Animal models of AKI–CKD transition represent important tools to study this pathology. We hypothesized that the administration of multiple doses of folic acid (FA) would lead to a progressive loss of renal function that could be characterized through biochemical parameters, histological classification and nuclear magnetic resonance (NMR) profiling.

Methods

Wistar rats were divided into groups: the control group received a daily intraperitoneal (I.P.) injection of double-distilled water, the experimental group received a daily I.P. injection of FA (250 mg kg body weight−1). Disease was classified according to blood urea nitrogen level: mild (40–80 mg dL−1), moderate (100–200 mg dL−1) and severe (>200 mg dL−1). We analyzed through biochemical parameters, histological classification and NMR profiling.

Results

Biochemical markers, pro-inflammatory cytokines and kidney injury biomarkers differed significantly (P< 0.05) between control and experimental groups. Histology revealed that as damage progressed, the degree of tubular injury increased, and the inflammatory infiltrate was more evident. NMR metabolomics and chemometrics revealed differences in urinary metabolites associated with CKD progression. The main physiological pathways affected were those involved in energy production and amino-acid metabolism, together with organic osmolytes. These data suggest that multiple administrations of FA induce a reproducible model of the induction of CKD. This model could help to evaluate new strategies for nephroprotection that could be applied in the clinic.
Identification of diagnostic markers for major depressive disorder by cross-validation of data from whole blood samples
Authors: Wang Huimei , Zhang Mingwei , Xie Qiqi , Yu Jin , Qi Yan , Yue Qiuyuan
Published: June 2019

Background

Major depressive disorder (MDD) is a severe disease characterized by multiple pathological changes. However, there are no reliable diagnostic biomarkers for MDD. The aim of the current study was to investigate the gene network and biomarkers underlying the pathophysiology of MDD.

Methods

In this study, we conducted a comprehensive analysis of the mRNA expression profile of MDD using data from Gene Expression Omnibus (GEO). The MDD dataset (GSE98793) with 128 MDD and 64 control whole blood samples was divided randomly into two non-overlapping groups for cross-validated differential gene expression analysis. The gene ontology (GO) enrichment and gene set enrichment analysis (GSEA) were performed for annotation, visualization, and integrated discovery. Protein–protein interaction (PPI) network was constructed by STRING database and hub genes were identified by the CytoHubba plugin. The gene expression difference and the functional similarity of hub genes were investigated for further gene expression and function exploration. Moreover, the receiver operating characteristic curve was performed to verify the diagnostic value of the hub genes.

Results

We identified 761 differentially expressed genes closely related to MDD. The Venn diagram and GO analyses indicated that changes in MDD are mainly enriched in ribonucleoprotein complex biogenesis, antigen receptor-mediated signaling pathway, catalytic activity (acting on RNA), structural constituent of ribosome, mitochondrial matrix, and mitochondrial protein complex. The GSEA suggested that tumor necrosis factor signaling pathway, Toll-like receptor signaling pathway, apoptosis pathway, and NF-kappa B signaling pathway are all crucial in the development of MDD. A total of 20 hub genes were selected via the PPI network. Additionally, the identified hub genes were downregulated and show high functional similarity and diagnostic value in MDD.

Conclusions

Our findings may provide novel insight into the functional characteristics of MDD through integrative analysis of GEO data, and suggest potential biomarkers and therapeutic targets for MDD.
On Simplicial Polytopic Numbers
Authors: Ufuoma Okoh , Ikhile Agun
Published: June 2019

The ultimate goal of this work is to provide in a concise manner old and new results relating to the simplicial polytopic numbers.
Analysis of the Production Components in the Soybean Crop in the Last Two Decades in the State of Parana and Brazil
Authors: Lazaretti Norma Schlickmann , Abraão Patrícia Clemente , Mata Tatiane Calandrino Da , Cardoso Kerolém Prícila Sousa , Cordeiro Noélle Khristinne , Souza Dablieny Hellen Garcia , Bernardi Daiane , Júnior Eurides Kuster Macedo
Published: June 2019

Introduction: Soy is an agricultural crop that has great economic importance. The analysis considering the cultivated area, the production and the yield of grains contributes to research and transfer of technology to the producers.

Aims: To adjust the mathematical model using simple linear regression analysis and correlation between the variables of planted area, production and productivity, in the state of Paraná and Brazil, in the last two decades.

Study Design: Data collection and research of information on the cultivation of soybeans in the state of Paraná and in Brazil on official websites

Place and Duration of Study: State University of Western Paraná, Post-Graduation in Agronomy, between July 2018 and December 2018.

Methodology: Data were obtained from the Portal of the Brazilian Institute of Geography and Statistics between 1997 and 2017. Simple linear regression analysis and Pearson correlation analysis were used.

Results: By analyzing the results, it is possible to observe significant increases in soybean production in both Paraná and Brazil over this 20-year period. Paraná achieved a 205% increase in planted area, 290% in production and 141% in average yield.

Conclusion: The simple linear regression and correlation analysis showed an adjustment between the cultivated area, the production and the average productivity in the soybean crop in the period from 1997 to 2017.
Protecting Effect of Vitamin E against Chromosomal Damage Induced by an Extremely Low-frequency Electromagnetic Field in Murine Bone Marrow Erythrocytes
Authors: Kheiry Elahe Vadaye , Haddad Farhang
Published: June 2019

Living organisms including human are exposed to an electromagnetic field from natural and industrial sources. Genotoxic effects of electromagnetic fields have been reported by several studies. Vitamin E is a lipid-soluble antioxidant that plays an important role in maintaining the integrity and function of cell membranes, nervous system, and reproductive system, among others, by functioning as a defence against oxidative damage. In this research, the protective effects of vitamin E against the chromosomal damage induced by extremely low-frequency electromagnetic field (ELEM) on bone marrow erythrocytes of adult male BALB/c mouse have been studied. Adult male BALB/c mice were intraperitoneally injected with vitamin E, with the dose of 200 mg/kg for 8 days and then exposed to ELEM with the intensity of 50Hz for 4 hours for 4 consecutive days. The mice were dissected and micronucleus assay was performed on the polychromatic erythrocytes (PCE) of their bone marrow. Results show that ELEM could increase the chromosomal damage judged by the higher frequency of MN compared to control. Results also revealed that the frequency of micronucleated polychromatic erythrocytes (MNPCE) had substantially decreased (p<0.00 1) in vitamin E- treated mice compared to untreated. Data suggest the protecting effect of vitamin E in bone marrow cells of Balb/C mice against the ELEM.
CARE Act backed by medical experts at House hearing
Authors: Knopf Alison
Published: June 2019

At a hearing by the House of Representatives Committee on Oversight and Reform last week, medical experts backed the Comprehensive Addiction Resources Emergency (CARE) Act (H.R. 2569). The legislation, introduced by Committee Chair Rep. Elijah E. Cummings (D‐Maryland) and Sen. Elizabeth Warren (D‐Massachusetts), is modeled on the bipartisan Ryan White Comprehensive AIDS Resources Emergency (CARE) Act passed three decades ago to combat the HIV/AIDS epidemic.
A Coherently Strained Monoclinic [111]PbTiO3 Film Exhibiting Zero Poisson's Ratio State
Authors: Tang Yunlong , Zhu Yinlian , Ma Xiuliang , Hong Zijian , Wang Yujia , Wang Wenyuan , Xu Yaobin , Liu Ying , Wu Bo , Chen Lang , Huang Chuanwei , Chen Longqing , Chen Zuhuang , Wu Haijun , Pennycook Stephen J.
Published: June 2019

[111]‐Oriented perovskite oxide films exhibit unique interfacial and symmetry breaking effects, which are promising for novel quantum materials as topological insulators and polar metals. However, due to strong polar mismatch and complex structural reconstructions on (111) surfaces/interfaces, it is still challenging to grow high quality [111] perovskite heterostructures, let alone explore the as‐resultant physical properties. Here, the fabrication of ultrathin PbTiO3 films grown on a SrTiO3(111) substrate with atomically defined surfaces, by pulsed laser deposition, is reported. High‐resolution scanning transmission electron microscopy and X‐ray diffraction reveal that the as‐grown [111]PbTiO3 films are coherent with the substrate and compressively strained along all in‐plane directions. In contrast, the out‐of‐plane lattices are almost unchanged compared with that of bulk PbTiO3, resulting in a 4% contraction in unit cell volume and a nearly zero Poisson's ratio. Ferroelectric displacement mapping reveals a monoclinic distortion within the compressed [111]PbTiO3, with a polarization larger than 50 µC cm−2. The present findings, as further corroborated by phase field simulations and first principle calculations, differ significantly from the common [001]‐oriented films. Fabricating oxide films through [111] epitaxy may facilitate the formation of new phase components and exploration of novel physical properties for future electronic nanodevices.
The Accelerating World of Graphdiynes
Authors: Sakamoto Ryota , Fukui Naoya , Maeda Hiroaki , Matsuoka Ryota , Toyoda Ryojun , Nishihara Hiroshi
Published: June 2019

Graphdiyne (GDY), a 2D allotrope of graphene, is first synthesized in 2010 and has attracted attention as a new low‐dimensional carbon material. This work surveys the literature on GDYs. The history of GDYs is summarized, including their relationship with 2D graphyne carbons and yearly publication trends. GDY is a molecule‐based nanosheet woven from a molecular monomer, hexaethynylbenzene; thus, it is synthesized by bottom‐up approaches, which allow rich variation via monomer design. The GDY family and the synthetic procedures are also described. Highly developed π‐conjugated electronic structures are common important features in GDY and graphene; however, the coexistence of sp and sp2 carbons differentiates GDY from graphene. This difference gives rise to unique physical properties, such as high conductivity and large carrier mobility. Next, the theoretical and experimental studies of these properties are described in detail. A wide variety of applications are proposed for GDYs, including electrocatalysts and energy devices, which exploit the carbon‐rich nature, porous framework, and expanded π‐electron system of these compounds. Finally, potential uses are discussed.
Self‐Supported and Flexible Sulfur Cathode Enabled via Synergistic Confinement for High‐Energy‐Density Lithium–Sulfur Batteries
Authors: Wang Zhuosen , Shen Jiadong , Liu Jun , Xu Xijun , Liu Zhengbo , Hu Renzong , Yang Lichun , Feng Yuezhan , Liu Jun , Shi Zhicong , Ouyang Liuzhang , Yu Yan , Zhu Min
Published: June 2019

Lithium–sulfur (Li–S) batteries have attracted much attention in the field of electrochemical energy storage due to their high energy density and low cost. However, the “shuttle effect” of the sulfur cathode, resulting in poor cyclic performance, is a big barrier for the development of Li–S batteries. Herein, a novel sulfur cathode integrating sulfur, flexible carbon cloth, and metal–organic framework (MOF)‐derived N‐doped carbon nanoarrays with embedded CoP (CC@CoP/C) is designed. These unique flexible nanoarrays with embedded polar CoP nanoparticles not only offer enough voids for volume expansion to maintain the structural stability during the electrochemical process, but also promote the physical encapsulation and chemical entrapment of all sulfur species. Such designed CC@CoP/C cathodes with synergistic confinement (physical adsorption and chemical interactions) for soluble intermediate lithium polysulfides possess high sulfur loadings (as high as 4.17 mg cm–2) and exhibit large specific capacities at different C‐rates. Specially, an outstanding long‐term cycling performance can be reached. For example, an ultralow decay of 0.016% per cycle during the whole 600 cycles at a high current density of 2C is displayed. The current work provides a promising design strategy for high‐energy‐density Li–S batteries.
Engineering Ultrafast Carrier Dynamics at the Graphene/GaAs Interface by Bulk Doping Level
Authors: Yang Jinghuan , Sun Quan , Liu Wei , Zhang Zhibin , Hu Xiaoyong , Liu Kaihui , Yang Hong , Misawa Hiroaki , Gong Qihuang
Published: June 2019

Carrier dynamics, the most fundamental process in electronics and optoelectronics, has drawn great attentions owing to its crucial role in property engineering of materials. Exploration and regulation of carrier dynamics are essential for designing devices with specific functions and optimizing their performances. However, the lack of conventional tools with simultaneous ultrafast temporal and ultrasmall spatial resolution has impeded direct observation and manipulation of carrier dynamics at both the femtosecond and nanometer scale. In this study, the direct observation and modulation of ultrafast carrier dynamics at the graphene/gallium arsenide (GaAs) interface is achieved by tuning the doping level of bulk GaAs. This successful characterization is performed using advanced in situ photoemission electron microscopy combined with the ultrafast pump–probe technique. It is found that a change in the doping level in GaAs can change its band bending and switch the hot‐carrier transfer direction at the graphene/GaAs interface with a lifetime reduction of nearly six times. This work paves the way of engineering ultrafast carrier dynamics at 2D interfaces by modifying the 3D bulk properties, and also provides a platform for fundamental studies of ultrafast physics with high spatial resolution.
Electrochemical Synthesis of Allylamines via a Radical Trapping Sequence
Authors: Sun Cao‐Cao , Lian Fei , Xu Kun , Zeng Cheng‐Chu , Sun Bao‐Guo
Published: June 2019

An electrochemical oxidative addition of sulfonamides and imide to allyl sulfones was developed for the facile synthesis of synthetically useful allylamines. This method avoids the use of transition metal catalysts and additional bases, which are commonly used for the synthesis of allylamines. Moreover, cheap and easily available NaI was employed as the mediator without use of an external supporting electrolyte. Radical trapping experiments showed that nitrogen‐centered radicals were involved in these transformations.

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