bluuebunny/crossref_metadata_2025 huggingface dataset:
All-optical tunable microwave filter with ultra-high peak rejection and low-power consumption
Authors: Liu Li , Liu Xing
Published: April 2020

We propose and experimentally demonstrate microwave photonic filters (MPFs) with high rejection ratios and large tuning ranges of the central frequency and bandwidth leveraging four cascaded opto-mechanical microring resonators (MRRs). As half waveguides of each MRR are free-hanging in the air, the nonlinear effects in the opto-mechanical MRRs could be efficiently excited. Consequently, the transmission characteristics of the cascaded MRRs could be flexibly manipulated by adjusting the input pump powers. When the resonant wavelengths of every two MRRs are tuned to be aligned, the transmission spectrum of the silicon device is a notch bimodal distribution with high extinction ratios. The optical carrier is fixed at the flat region of the bimodal distribution. Under optical double sideband (ODSB) modulation, MPFs with high rejection ratios could be achieved due to the high extinction ratio of the cascaded rings. Moreover, the central frequency and bandwidth of the MPFs could be tuned by properly adjusting the pump powers. In the experiment, with a low power of 2.56 mW, the MPF central frequency and bandwidth could be tuned from 7.12 GHz to 39.16 GHz and from 11.3 GHz to 17.6 GHz, respectively. More importantly, the MPF rejection ratios are beyond 60 dB. Furthermore, during the bandwidth tuning process, an MPF response with approximately equiripple stopband could be realized. Owing to the dominant advantages of high rejection ratios, large tuning ranges, low power consumption and compact size, the silicon device has many significant applications in on-chip microwave systems.
Electrically driven source of time-energy entangled photons based on a self-pumped silicon microring resonator
Authors: Garrisi Francesco , Sabattoli Federico Andrea , Sam Savda , Barone Andrea , Massara Micol Previde , Pirzio Federico , Morichetti Francesco , Melloni Andrea , Liscidini Marco , Galli Matteo , Bajoni Daniele
Published: April 2020

Time-energy entangled photon pairs are fundamental resources for quantum communication protocols since they are robust against environmental fluctuations in optical fiber networks. Pair sources based on spontaneous four-wave mixing in silicon microring resonators usually employ expensive external tunable lasers to compensate for ambient fluctuations; adopting self-pumped configurations, instead, lifts the need for such external source. Here we demonstrate the emission of time-energy entangled photon pairs at telecom wavelengths from a silicon self-pumped ring, obtaining a Franson interference fringe with

93.9
%
±
0.9
%

visibility.
Sub-two-cycle octave-spanning mid-infrared fiber laser
Authors: Huang J. , Pang M. , Jiang X. , Köttig F. , Schade D. , He W. , Butryn M. , Russell P. St. J.
Published: April 2020

Compact and powerful ultrafast light sources at high pulse repetition rates, based on mode-locked near infrared fiber lasers, are now widely available and are being used in applications such as frequency metrology, molecular spectroscopy, and laser micro-machining. The realization of such lasers in the mid-infrared has, however, remained a challenge for many years. Here we report a record-breaking three-stage fiber laser system that uses an Er-doped fluoride fiber as gain medium, delivering W-level few-cycle pulses at 2.8 µm at a repetition rate of 42.1 MHz. A fiber-based seed oscillator, cavity dispersion-managed by a pulse-stretcher, generates near-100-fs mid-infrared pulses with

>

110

n
m

spectral bandwidth. These pulses are amplified to an average power of

∼

1

W

in a chirp-engineered fiber amplifier, and then compressed to

∼

16

f
s

in a short length of highly nonlinear ZBLAN fiber, resulting in a more-than-octave-wide spectrum reaching from 1.8 µm to 3.8 µm with a total power of 430 mW.
Study on multiple waveguide platforms for waveguide integrated Raman spectroscopy
Authors: Lee Wooje , Muñoz-Galindo Pablo , Hegeman Ivo , Yong Yean-Sheng , Dijkstra Meindert , García-Blanco Sonia M. , Offerhaus Herman L.
Published: April 2020

Waveguide Raman spectroscopy uses the evanescent field outside a waveguide to probe the analyte on the surface of the chip, permitting to selectively study thin films or nanostructures on top of the waveguide while benefiting from the long iteration path of the excitation with the analyte. Both the polarization of the excitation mode as well as the refractive index contrast of the waveguide platform play an important role in the Raman excitation process as well as the coupling efficiency of the generated Raman signal back into the waveguide. In this article, we characterize three waveguide platforms of different refractive index contrasts for waveguide Raman, namely Al2O3, Si3N4 and TiO2 on SiO2. Toluene was used as a test analyte. Both background and analyte were measured for quasi- transverse electric (quasi-TE) and quasi- transverse magnetic (quasi-TM) modes. TM modes generate less background than TE modes due to less confinement of the mode in the waveguide core materials. A combination of Si3N4 and quasi-TM polarization led to the highest SNR in this study.
El Escudo de Clonbrin (Irlanda) y las Estelas del Suroeste. Una aproximación a los escudos con escotadura en «V» del Bronce Final Atlántico
Authors: González Jorge Del Reguero
Published: April 2020

El presente trabajo constituye una aproximación al estudio de los escudos con escotadura en «V» del Bronce Final atlántico. Para ello, pondremos especial énfasis en analizar el escudo de piel de Clonbrin y su analogía con otros escudos de tipo Herzsprung, haciendo especial referencia a las estelas de guerrero de la Península Ibérica. Además, se presentan los resultados obtenidos tras los trabajos experimentales desarrollados en torno al tipo de soporte, el proceso de elaboración y la funcionalidad de los escudos de piel.
Tejada La Vieja (Escacena del Campo, Huelva) y la producción y consumo vitivinícola
Authors: Toscano-Pérez Clara
Published: April 2020

Se presentan las más recientes novedades obtenidas gracias a las últimas actividades llevadas a cabo en el asentamiento de Tejada la Vieja (Escacena del Campo, Huelva) por el grupo de investigación “Vrbanitas. Arqueología y Patrimonio (HUM-132)” de la Universidad de Huelva. Como parte del estudio y análisis de las estructuras que fueron exhumadas en el pasado, una de las novedades que aportamos vincula algunos de sus edificios con espacios relacionados con el consumo y la producción de vino, de manera que consideramos debió ser una de sus principales actividades.
El Potro Desempotrado: el caballo ibérico de la Covatilla (Marchena, Sevilla)
Authors: Ávila Javier Jiménez
Published: April 2020

El caballo ibérico de La Covatilla (Marchena), actualmente conservado en el Museo Arqueológico Provincial de Sevilla, fue publicado cuando se encontraba encastrado en la pared de un edificio de dicha localidad. Su extracción en los años ochenta ha permitido reconocer una serie de elementos hasta entonces ocultos que se relacionan con un arnés ecuestre correspondiente al tiro de un vehículo. Se convierte, así, en la primera escultura ibérica de gran formato que incluiría un carro. Se adscribe a un monumento conmemorativo relacionado con la ideología militar propia de la aristocracia ibérica.
A cerâmica de engobe vermelho dos povoados do 4°/3° milénio A.N.E. de São Pedro (Redondo, Alentejo Central).
Authors: Costeira Catarina , Mataloto Rui
Published: April 2020

O sítio arqueológico de São Pedro (Redondo, Alentejo), ocupado entre os finais do 4º e grande parte do 3º milénio a.n.e. apresenta um amplo conjunto de recipientes cerâmicos com características morfo-tipológicas, métricas e tecnológicas muito diversificadas. Este trabalho centra-se nas técnicas de tratamento de superfície dos recipientes cerâmicos, mais concretamente na aplicação de engobes e aguadas de tonalidade vermelha. Com esta reflexão pretendemos valorizar o sentido estético e simbólico da cor vermelha na cultura material das comunidades do Neolítico final / Calcolítico no Sudoeste peninsular, uma vez que se trata de um tema pouco abordado nos trabalhos arqueológicos mais recentes.
Os metais das necrópoles de Cistas de Casas Velhas (Melides) e da Provença (Sines). O encontro de antigas e novas tecnologias no Bronze Pleno do Sudoeste
Authors: Valério Pedro , Araújo Maria Fátima , Soares António M. Monge , Soares Joaquina , Da Silva Carlos Tavares
Published: April 2020

O estudo consiste na caracterização do espólio metálico das necrópoles de cistas de Casa Velhas e da Provença. Os artefactos de base cobre são compostos por cobre arsenical (2,03-5,64% As), exceptuando-se um “anzol” em bronze, liga que constitui uma das inovações do Bronze Pleno do Sudoeste, tal como a prata, aqui utilizada em ornamentos: anel (99,7% Ag) e bracelete (94,5% Ag; 5,41% Cu). Uma conta em ouro (12,6% Ag; <0,04% Cu) terá sido manufacturada em ouro de aluvião, tal como a maioria dos ouros pré-históricos. Por último, integram-se os resultados na metalurgia no sul de Portugal durante o II milénio a.C.
Castelo Velho de Freixo de Numão. Enquadramento geomorfológico
Authors: Araújo Assunção , Soares Laura , Gomes Alberto
Published: April 2020

A área em que se enquadra o sítio do Castelo Velho tem uma posição muito especial porque corresponde a uma espécie de encruzilhada onde a superfície de aplanamento da Meseta começa a ser movimentada e desnivelada pelo desligamento esquerdo tardi-varisco Manteigas-Vilariça-Bragança e, simultaneamente, entalhada pela erosão regressiva do Douro e seus afluentes. Com movimentação tectónica durante o Quaternário, o acidente referido é sublinhado pela rigidez do Vale da Vila, prolongando-se para Norte e originando o graben da Vilariça, enquanto para sul define o fosso tectónico da Longroiva. O sítio de Castelo Velho, dominando o Vale da Vila e a superfície de Foz Côa, permite a observação de extensas áreas sobretudo de uma parte significativa da meseta setentrional, até à serra da Marofa. À posição de charneira entre os planaltos ocidentais e a superfície da Meseta associa-se uma variação climática acentuada, devida ao profundo encaixe da rede hidrográfica, enquadrando-se no Douro Superior da Região Demarcada do Douro.
Voltar a Castelo Velho de Freixo de Numão: pensar a reconfiguração cultural dum recinto pré-histórico do Alto Douro português
Authors: Lopes Susana Soares
Published: April 2020

A revisitação de Castelo Velho de Freixo de Numão permite admitir a hipótese de que o recinto foi palco, entre o 3.º e o 2.º milénio AC, de acções que configuram duas formas de representação do mundo.
AS ABÓBADAS DE CAIXOTÕES NA ARQUITETURA PORTUGUESA DO SÉCULO XVI E O CONTRIBUTO DE JOÃO DE RUÃO
Authors: Vaz Ana Margarida , Lobo Rui
Published: April 2020

No Renascimento, o emprego de arcos quartelados e de abóbadas de caixotões constituiu um recurso marcante na arte e na arquitetura, dada a sua associação sugestiva à arte e arquitetura romanas. Em Coimbra, João de Ruão será um personagem fundamental na divulgação destes novos elementos formais no âmbito da produção de peças de arquitetura específicas. Na sua senda, Diogo de Castilho irá aplicar abóbadas de caixotões nas igrejas dos novos colégios (Graça, S. Jerónimo) afirmando a cidade do Mondego como um importante foco da arquitetura portuguesa do Renascimento. Uma questão importante será a definição de uma formulação “canónica” para essas abóbadas que tenderão (em finais do século XVI) para a conformação de um número ímpar de fiadas, com a afirmação de uma cadeia central de caixotões – uma evolução que replicava o que sucedera em outros contextos artísticos, mais “centrais”, da Europa, como a própria Itália.
“DAMIANO DI RUAN” ARCHITETTO PORTOGHESE IN ITALIA E LA CASAMATTA DI TORINO
Authors: Vaz Ana Margarida , Bertini Giuseppe
Published: April 2020

Un architetto portoghese, Damiano di Roan, fu inviato a Parma da Don Duarte alla sorella Maria che era sposata al principe Alessandro Farnese affinché potesse progredire nell'arte delle fortificazioni. Fu inviato ad Ancona presso Francesco Paciotto e successivamente a Torino presso Ferrante Vitelli che lavorava alla Cittadella. Nel 1575 in seguito ad un litigio, in cui intervenne anche il duca Emanuele Filiberto di Savoia, venne rinviato a Parma. I principi Farnese non lo vollero trattenere e decisero di mandarlo a Roma. Non si conosce la sorte dell'architetto, che è del tutto ignorato dai documenti degli archivi portoghesi.
OURIVESARIA EM PEDRA. JOÃO DE RUÃO E A PRODUÇÃO EM METAL PRECIOSO. 1530-1580
Authors: Vaz Ana Margarida , Silva Nuno
Published: April 2020

Neste artigo aborda-se a estreita relação entre a obra de João de Ruão e a ourivesaria do renascimento, como constatada por diversos autores. Através do confronto do conjunto de obras do escultor com alfaias em prata executadas no mesmo período aprofundamos este relacionamento, que culminará com a campanha da Capela do Santíssimo Sacramento da Sé de Coimbra.
A OFICINA DE JOÃO DE RUÃO: OS ESCULTORES, A RELAÇÃO OFICINAL E A GESTÃO DO TRABALHO
Authors: Vaz Ana Margarida , Gonçalves Carla
Published: April 2020

Este artigo pretende estruturar o conhecimento sobre a oficina de João de Ruão, colocando em discussão o problema das relações oficinais, da gestão do trabalho e dos escultores que a historiografia artística tem associado ao Mestre normando.Partindo da organização socio-laboral coimbrã, e inquirindo sobre qual seria o ambiente formativo deste artista na Normandia – um assunto tão inexplorado quanto difícil, pela parcimónia de dados – , que também terá moldado os seus hábitos de trabalho, revisitam-se criticamente os nomes dos artistas que, em Coimbra, têm vindo a associar-se ao estaleiro do Mestre, com o sentido de responder à pergunta sobre a dimensão humana e social daquela que tem vindo a considerar-se a maior e mais profícua oficina de escultura do século XVI.

Tentando dar resposta às questões colocadas têm, também, de averiguar-se os moldes de associação laboral, num quadro de relações que parte do aprendizado até à integração dos artistas no mercado, bem como as designações dos sujeitos envolvidos neste processo, nomeadamente a significação de criado, situada entre o apaniguado, ou protegido, o serviçal generalista e o aprendiz que pretende especializar-se num ofício.
In Memoriam Maria Helena da Rocha Pereira Paradigma de cidadã e de dedicação ao ensino e à cultura
Authors: Ferreira José Ribeiro
Published: April 2020

In Memoriam Maria Helena da Rocha Pereira
Assessment of Target Volume Definition for Radiosurgery of Atypical Meningiomas with Multimodality Imaging
Authors: Demiral Selcuk , Beyzadeoglu Murat , Dincoglan Ferrat , Sager Omer
Published: April 2020

Objective
Meningiomas are most common intracranial benign tumors comprising around one third of all intracranial neoplasms, and typically have benign and indolent nature with slow-growing behaviour. Benign meningiomas are slow growing tumors typically following an indolent disease course. Nevertheless, atypical or anaplastic meningiomas may follow a more aggressive disease course with invasion of critical structures and recurrences. In the current study, we evaluate the incorporation of magnetic resonance imaging (MRI) for radiosurgery treatment planning of atypical meningiomas.

Materials and Methods
Atypical meningioma radiosurgery target volume determination with and without incorporation of MRI has been evaluated. Ground truth target volume used as the reference has been outlined by the board-certified group of radiation oncologists after comprehensive assessment, thorough collaboration and consensus.

Results
Target volume definition by use of Computed Tomography (CT)-only imaging and by CT-MR fusion based imaging has been comparatively evaluated in this study for linear accelerator (LINAC)-based radiosurgical management of atypical meningioma. Ground truth target volume defined by the board-certified radiation oncologists after detailed evaluation, collaboration, colleague peer review and consensus has been found to be identical to target determination by use of CT-MR fusion based imaging.

Conclusion
Despite significant progress in neurosurgical techniques over the years, complete surgical resection may not be feasible in the presence of meningiomas located at eloquent brain areas in close association with important neurovascular structures. RT may have a role in multidisciplinary management of meningiomas. Incorporation of MRI into treatment planning for radiosurgery of atypical meningiomas may improve target definition despite the need for further supporting evidence.
The Intersection of Cultural Characteristics and Genetics on the Prevalence of Delayed Sleep Phase Syndrome in Brazilian and Japanese Adults
Authors: Estafanous Abram , Sedky Karim
Published: April 2020

Delayed sleep phase syndrome (DSPS) is a circadian rhythm disorder where individuals experience difficulty modifying the time they go to sleep and wake up in response to environmental changes. The circadian rhythm itself is regulated by a variety of clock genes, and various other genes (e.g., AA-NAT gene, CKIϵ gene) code for proteins that regulate clock genes. Various polymorphisms of the clock gene influencers have been shown to increase susceptibility to DSPS. This paper seeks to examine how certain cultural characteristics (e.g., napping, timing of meals, exposure to artificial light) and the presence of the AA-NAT gene (G619A polymorphism) and the CKIϵ gene (S408N polymorphism) influence the prevalence of DSPS amongst Japanese and Brazilian populations.
Assessment of Ocimum Basilicum as Potentially Fruit Flies Attractant
Authors: Abdullah Selma M. O. , Abbas Amani M. K. , Ali Hind A. , Abdelmagid Faiza M. , Adam Abubaker H. M.
Published: April 2020

The Basil plant (Ocimumbasilicum L) is an annual herb; belongs to family Lamiaceae. It is found to be an important source for Methyl Eugenol (ME), the fruit flies attractant. This study was carried out at Shendi area with main objective to assess the amount of ME extracted from Ocimumbasilicumplant to evaluate its potentiality as fruit fly attractant. Plants of basil were grown till to maturity, then the differential harvest of leaves, flower and seeds were chemically investigated for volatilome. Five basil formulations (paste and powder of leaves, paste and powder of flowers, isolated ME from basil oil) were used for trapping potential of Bactrocera spp in mango orchards, as compared to the synthetic ME. The oil was extracted using Soxhlet apparatus, steam and water distillation, and analyzed using GCMS. The results revealed that highest extracted oil percentages was obtained from flowers, leaves, seed and stem were 5.75%, 3.03%, 0.02% and 0.21% respectively. Moreover, the basil traps catch was found to be lower compared with that of the control traps. Furthermore, when extracted ME from basil plant was compared with the standard synthetic, it gave lower catch fruit flies numbers, but the difference was not significant (>0.05). In conclusion, the basil raw derivates are confirmed not to be attractive for flies but the oil distillable from the leaves could be in force of its attractant ME contents and insecticide potency.
Los “compromisos” de la dominación. Una aproximación al Behemoth de Franz Neumann
Authors: Abril Francisco
Published: April 2020

En el presente artículo nos proponemos explicitar cuáles son las principales características que Franz Neumann –autor del círculo “externo” de la primera Teoría Crítica– le atribuye a la dominación socio-política. Para abordar esta cuestión es necesario reseñar algunas de las principales tesis de su clásico libro sobre el nacional-socialismo titulado Behemoth, prestando especial atención a su análisis relativo a la destrucción de la racionalidad jurídica. Nos interesa, puntualmente, responder a la siguiente pregunta: ¿hay en su propuesta una concepción de dominación que presuponga, además de coerción, consentimiento y participación de los grupos dominados? Para poder dar cuenta de las distintas aristas que detenta este interrogante, consideramos necesario retomar los aportes que hace Axel Honneth –uno de los tantos teóricos contemporáneos que instan a recuperar los estudios de Neumann– en su libro Crítica del poder, donde hace mención a la existencia de “relaciones bilaterales de dominio”. Aquí veremos que Neumann ofrece precisiones para responder al problema de la “dominación bilateral” –así lo llamaremos–, pero con limitaciones nada desdeñables. Limitaciones que, y ésta es una sugerencia que haremos al final del artículo, podrían sortearse a partir de un diálogo más abarcador que involucre a otros miembros del círculo “externo”
Conflictos de valores y conflictos de intereses. La comprensión de la conflictividad en el pensamiento de Julio De Zan
Authors: Michelini Dorando J.
Published: April 2020

El artículo expone sintéticamente, en primer término, algunas ideas clave de la teoría ético-discursiva en relación con la resolución de conflictos. Luego se presentan las observaciones críticas que realiza Julio De Zan a la Ética del discurso en el sentido de que los discursos prácticos no serían aptos para resolver los conflictos de valores, los conflictos de intereses y los conflictos político-sociales, como también su propuesta de complementar la Ética del discurso con un aporte hermenéutico y una estrategia de cooperación mutua para la solución de aquellos conflictos que no pueden ser resueltos mediante el discurso argumentativo. Esta estrategia no estaría orientada a alcanzar un consenso entre las partes, sino a lograr un modus vivendi razonable y pacífico. El artículo cierra con una ponderación crítica de las reflexiones de Julio De Zan y con la mención de algunos interrogantes que se plantean a partir de su propuesta de complementación de la Ética del discurso.
Emociones constructoras de paz desde los niños y las niñas del grado transición: representaciones desde su experiencia
Authors: Tamayo Zuluaga Diana María , Tabares López Lorena , Muñoz María Fernanda , Segura Sierra Sandra , Atehortúa Palacios Yakeline
Published: April 2020

En este artículo se presentan los avances de una investigación que tiene como objetivo comprender las representaciones sobre las emociones que hacen posible la paz, desde los niños y niñas de cinco años, de tres regiones colombianas (Antioquia, Caldas y Valle). Es un estudio cualitativo de alcance comprensivo que busca comprender los sentidos y los significados de los sujetos en sus propios contextos, y muestra algunas categorías teóricas tales como educación para la paz, representaciones, emociones y paz, las cuales dan soporte al problema planteado. El desarrollo metodológico partió de una encuesta socio-demográfica y un cuestionario emocional aplicado a cada estudiante; posteriormente, se aplicaron cuatro talleres. Un primer taller de sensibilización de las emociones, un segundo taller de cultura de paz y dos talleres más en los que la técnica empleada fue la entrevista semiestructurada. Con cada niño y niña se elaboró el árbol de emociones y emociones para la paz, utilizando los emoticones como recurso didáctico que los niños emplearon a fin de representar las emociones, de acuerdo con las narraciones realizadas por cada estudiante. Los resultados plantean la necesidad de escuchar las voces de los niños y las niñas en la construcción de la paz, así como de hacer visible lo que ellos piensan y representan de las emociones. Se evidencian avances en la descripción de las emociones, así como en la comprensión y la representación desde los significados, las causas, las consecuencias, la temporalidad y la oposición emocional; se observó, de manera continua, motivación e interés en las actividades por parte de los niños y niñas.
Alfabetizar para la democracia
Authors: Rojas García Ilene
Published: April 2020

El artículo reflexiona en torno a los mecanismos de comprensión y solución de los problemas sociales, enmarcados en los procesos de enseñanza y aprendizaje del lenguaje escrito. Interesa revisar, en primera instancia, el concepto de alfabetización como punto de partida que trasciende la correspondencia fonográfica; posteriormente, reflexionar sobre la idea de democracia como uno de los puntos en la agenda educativa, cuyo significado traspasa la idea general de elección popular. Finalmente, determinar el salto que debe emprender la alfabetización para trascender las prácticas escolares, hacia la posibilidad de forma
Aproximación a la educación basada en los derechos humanos y a la educación para la paz en la educación superior. Actividades prácticas para la enseñanza de la lengua inglesa
Authors: Martínez Lirola María
Published: April 2020

Este artículo ofrece una aproximación a los enfoques educativos que roponen la educación basada en los derechos humanos (EBDH) y la educación para la paz (EP), con el fin de reflexionar sobre los be-neficios de ambos enfoques, además de ofrecer propuestas reales de actividades prácticas que se puedan llevar a la práctica en la educación superior. Las actividades que se presentan se han llevado a cabo en una asignatura de lengua inglesa en la Universidad de Alicante. Dichas actividades tienen como fina-lidad que el alumnado reflexione sobre la importancia de los derechos humanos y la paz, a la vez que adquiere destrezas en la lengua extranjera. Además, ambos enfoques potencian la capacidad crítica, la conciencia social y los valores. Se preparó una encuesta a fin de conocer la opinión del alumnado sobre determinados aspectos de ambos enfoques.
Programa de talento matemático en educación básica
Authors: Butto Zarzar Cristianne María , Delgado Joaquín
Published: April 2020

Se presenta un estudio sobre la identificación y el desarrollo del talento matemático en estudian-tes de educación básica primaria y secundaria fundamentado en el Modelo de Enriquecimiento Escolar de Renzulli. La metodología usada fue de tipo mixto con diseño incrustado concurrente de modelo dominante. Las dos etapas del estudio consistieron en: a) detectar estudiantes con talento matemático en educación primaria básica y secundaria en lo que se refiere a los procesos de generalización; y b) diseñar y aplicar un programa de enriquecimiento extraescolar con estu-diantes de educación primaria básica y secundaria en lo se que refiere a los procesos de generali-zación en ambiente eXpresser y Google Maps, así como en la hoja de cálculo Excel. El programa de enriquecimiento extraescolar mostró ser efectivo, pues los alumnos lograron transitar hacia un pensamiento multiplicativo.
Citrate synthase desuccinylation by SIRT5 promotes colon cancer cell proliferation and migration
Authors: Ren Mengmeng , Yang Xin , Bie Juntao , Wang Zhe , Liu Minghui , Li Yutong , Shao Genze , Luo Jianyuan
Published: April 2020

Citrate synthase (CS), the rate-limiting enzyme in the tricarboxylic acid (TCA) cycle catalyzes the first step of the cycle, namely, the condensation of oxaloacetate and acetyl-CoA to produce citrate. The expression and enzymatic activity of CS are altered in cancers, but posttranslational modification (PTM) of CS and its regulation in tumorigenesis remain largely obscure. SIRT5 belongs to the nicotinamide adenine dinucleotide (NAD)+-dependent deacetylase sirtuin family and plays vital roles in multiple biological processes via modulating various substrates. Here, we show that SIRT5 interacts with CS and that SIRT5 desuccinylates CS at the evolutionarily conserved residues K393 and K395. Moreover, hypersuccinylation of CS at K393 and K395 dramatically reduces its enzymatic activity and suppresses colon cancer cell proliferation and migration. These results provide experimental evidence in support of a potential therapeutic approach for colon cancer.
The effect of soil water content and biochar on rice cultivation in polybag
Authors: Paiman  , Effendy Iqbal
Published: April 2020

Rice (Oryza sativaL.) production is important in the national food of Indonesia. The growth and yield of rice can be increased by the soil water supply and biochar application into the soil in a polybag. Water is a unique material resource that plays a vital role in agriculture. Biochar is a carbon-rich product obtained from biomass and can hold water and nutrients, making them more available to plants. The biochar used in this study was made from rice husks. This study aims to determine the effect of soil water content and biochar application in the soil on the growth and yield of rice in the polybag. The experiment appears to be a randomized multifactorial design with one factor being water content and the other being biochar application rate. A completely random design usually suggests only one factor in the experimental design. The first factor was soil water content consisting of two levels, i.e.: field capacity and soil waterlogging. The second factor was the biochar application consisting of four doses i.e.: 0; 14; 28; and 42 tons/ha. The results of the research showed that rice cultivation with soil water-logging is better than field capacity on the tillers number, panicle length, and harvest index. Without biochar application was given higher tillers number, but biochar dose of 14 tons/ha produced wider leaf area. There was a significant interaction between soil water content and biochar application on the dry weight of roots, shoots, and grains. The treatment combination of soil waterlogging and biochar dose of 14 tons/ha was most effective at increasing the growth and yield of rice in a polybag.
Complement-Dependent Synaptic Uptake and Cognitive Decline after Stroke and Reperfusion Therapy
Authors: Alawieh Ali M. , Langley E. Farris , Feng Wuwei , Spiotta Alejandro M. , Tomlinson Stephen
Published: April 2020

Despite the success of reperfusion therapy in significantly reducing the extent of infarct expansion after stroke, the effect of revascularization on poststroke neuroinflammation and the role of anti-inflammatory strategies in postreperfusion era are yet to be explored. Here, we investigate whether the neuroinflammatory response may still contribute to neurologic deficits after reperfused stroke by using targeted complement inhibition to suppress poststroke neuroinflammation in mice with or without concurrent reperfusion therapy. Complement inhibition was achieved using B4Crry, an injury site-targeted inhibitor of C3 activation. Following embolic stroke in male C57bl/6 mice, thrombolysis using tissue-plasminogen activator (t-PA) reduced injury and improved motor deficits, but did not improve cognitive outcomes. After both reperfused and non-reperfused stroke, complement activation and opsonization of hippocampal synapses directed ongoing microglia-dependent phagocytosis of synapses for at least 30 d after stroke, leading to a loss of synaptic density that was associated with cognitive decline. B4Crry treatment, alone or in combination with tPA, limited perilesional complement deposition, reduced microgliosis and synaptic uptake, and improved cognitive outcome without affecting regenerative responses. Furthermore, complement inhibition improved the safety, efficacy, and treatment window of reperfusion therapy with t-PA by limiting hemorrhagic transformation. This work thus demonstrates that poststroke neuroinflammation contributes to hemorrhagic transformation and progression of neurodegenerative responses in the brain even following early and successful revascularization.

SIGNIFICANCE STATEMENTThis study addresses two major challenges facing the treatment of stroke in the era of reperfusion therapy: hemorrhagic transformation and the disconnect between successful revascularization and functional outcomes. We studied how complement-dependent neuroinflammation drives the pathophysiology behind these challenges using a translationally relevant strategy. Complement inhibition was achieved using B4Crry, an injury site-targeted inhibitor of C3 activation. Following embolic stroke, pharmacological thrombolysis limited infarct size, but did not prevent complement activation. In reperfused and non-reperfused stroke, complement activation and opsonization of hippocampal synapses resulted in synaptic phagocytosis and subsequent cognitive decline. B4Crry treatment limited perilesional complement deposition, reduced microgliosis and synaptic uptake, and improved cognitive outcomes. Complement inhibition also improved the safety, efficacy, and treatment window of thrombolytic therapy.
Efectos de la danza folclórica y urbana sobre el desarrollo motor en grado preescolar del colegio pablo vi en bogota
Authors: Uscategui Ciendua Alix Johana
Published: April 2020

La investigación evaluó los efectos de un programa de danza urbana y folclórica sobre el desarrollo motor, implementado durante ocho semanas en secciones de 90 minutos, en 44 niños del colegio distrital Pablo VI de Bogotá, entre de los 4 y los 7 años (m= 5.64 DE ± 0.68); con enfoque cuantitativo, de alcance descriptivo, de pre y post test, con la comparación dos grupos experimentales GE1 n=25 (danza folclórica) y GE2 n=19 (danza urbana). Se evaluaron la talla y el peso, y la prueba TGMD-2 para medir el desarrollo motor; el análisis estadístico se realizó con el software SPSS v. 25, la prueba normalidad Shapiro Wilk, las variables presentaron distribución normal, y el valor de significancia fue p < 0.05. Los resultados obtenidos indican efectos positivos en las habilidades motrices evaluadas a partir de la intervención. Se evidencia un aumento porcentual por encima de un 50% en el componente de manipulación, y del componente locomotor en un 31%. Se recomienda incluir en los programas académicos escolares la danza como medio de estimulación y desarrollo motriz de los niños.
Representaciones sociales sobre actividad física y educación física en docentes bogotanos
Authors: Camargo Rojas Diana Alexandra , Moreno Zabaleta Linda
Published: April 2020

En contextos escolares la educación física se reconoce como el escenario para la promoción de la AF, no obstante en algunos colegios los docentes amplian los conceptos de la educación física tradicional hacia otras formas de movimiento. Por esta razón, el presente estudio busca comprender las representaciones sociales de docentes bogotanos frente a la actividad física y la educación física. El presente estudio tiene un paradigma interpretatio, con enfoque cualitativo y diseño narrativo. Se realizaron entrevistas a profundidad a nueve docentes de la Localidad de Suba y seis docentes de la localidad de ciudad Bolívar. La información se registro en matrices comparativas, cuyo contenido fueron los discursos descritos por los docentes de acuerdo a las categorías y sub-categorías establecidas. Esta investigación arrojó que las representaciones sociales de los docentes de Educación Física entrevistados tienen varios aspectos en común; con respecto a la Actividad Física ellos manifiestan que su práctica es fundamental para el desarrollo tanto físico, emocional como social de las personas. La Educación Física desde las representaciones se relaciona con la salud, pero en la práctica continua implementando estrategias basadas en el deporte y la higiene corporal.
A Reflection on 50 Years of John Maynard Smith’s “Protein Space”
Authors: Ogbunugafor C Brandon
Published: April 2020

In this Perspectives article, Ogbunugafor revisits a famous and influential analogy introduced by renowned evolutionary biologist John Maynard Smith in a 1970 manuscript entitled “Natural selection and the concept of protein space (Smith 1970)...

In 1970, John Maynard Smith published a letter, entitled “Natural Selection and the Concept of a Protein Space,” that proposed a simple analogy for the incremental process of adaptive evolution. His “Protein Space” analogy contains the substrate for many central ideas in evolutionary genetics, and has motivated important discoveries within several subdisciplines of evolutionary science. In this Perspectives article, I commemorate the 50th anniversary of this seminal work by discussing its unique legacy and by describing its intriguing historical context. I propose that the Protein Space analogy is not only important because of its scientific richness, but also because of what it can teach us about the art of constructing useful and subversive analogies.
Intramuscular Hematoma as a Manifestation of IgA Vasculitis
Authors: Azer Sally , File Wilson , Leazer Rianna
Published: April 2020

We describe an atypical pediatric case of immunoglobulin A vasculitis (IgAV), also referred to as Henoch-Schönlein purpura, in which formation of spontaneous hematoma of the paraspinal muscles developed. Spontaneous or unprovoked hematomas rarely occur in IgAV. These manifestations have not been described specifically in the pediatric literature as coinciding with IgAV. These findings are alarming for nonaccidental trauma, particularly in a patient without underlying blood dyscrasia. Our objective for this report is to highlight the possible association of muscular hematoma formation with IgAV and to help providers consider this association when trauma and hemophilia has been ruled out.
Influence of immune status on the airborne colonization of piglets with methicillin-resistant staphylococcus aureus (MRSA) clonal complex (CC) 398
Authors: Rosen Kerstin , Ebner Friederike , Schmidt Stefanie , Hartmann Susanne , Merle Roswitha , Friese Anika , Roesler Uwe
Published: April 2020

Colonized vertebrates including humans and pigs are to date the main reservoirs of livestock-associated Methicillin-resistantStaphylococcus aureus(LA-MRSA). Currently, the mechanisms underlying colonization of pigs are not fully understood.

We investigated the influence of piglet pre-immune status on airborne MRSA colonization. Three groups of MRSA-negative piglets were primed and exposed to airborne LA-MRSA (104colony forming units (cfu)/m3) in an aerosol chamber for 24 h. One group was treated intramuscularly with dexamethasone (1 mg/kg body weight) to imitate weaning stress. The second group was exposed to bacterial endotoxin containing MRSA aerosol. Both conditions play a role in the development of multifactorial diseases and may promote MRSA colonization success. The third group served as control.

The piglets' MRSA status was monitored for 21 days via swab samples. At necropsy, specific tissues and organs were analyzed. Blood was collected to examine specific immunological parameters.

The duration of MRSA colonization was not extended in both treated groups compared to the control group, indicating the two immune-status influencing factors do not promote MRSA colonization. Blood sample analysis confirmed a mild dexamethasone-induced immune suppression and typical endotoxin-related changes in peripheral blood. Of note, the low-dose dexamethasone treatment showed a trend of increased MRSA clearance.
Shared gray matter alterations in individuals with diverse behavioral addictions: A voxel-wise meta-analysis
Authors: Qin Kun , Zhang Feifei , Chen Taolin , Li Lei , Li Wenbin , Suo Xueling , Lei Du , Kemp Graham J. , Gong Qiyong
Published: April 2020

Background and aims

Numerous studies on behavioral addictions (BAs) have reported gray matter (GM) alterations in multiple brain regions by using voxel-based morphometry (VBM). However, findings are poorly replicated and it remains elusive whether distinct addictive behaviors are underpinned by shared abnormalities. In this meta-analysis, we integrated VBM studies on different BAs to investigate common GM abnormalities in individuals with BAs.

Methods

We performed a systematic search up to January 2019 in several databases for VBM studies investigating GM differences between individuals with BAs and healthy controls. The reference lists of included studies and high-quality reviews were investigated manually. Anisotropic effect-size signed differential mapping was applied in this meta-analysis.

Results

Twenty studies including 505 individuals with BAs and 564 healthy controls met the inclusion criteria. Compared with healthy controls, individuals with BAs showed GM atrophy in the left anterior cingulate (extending to the left medial superior frontal gyrus and bilateral orbitofrontal gyrus), right putamen and right supplementary motor area. Subgroup analysis found heterogeneity in gender and subtypes of BAs. Meta-regression revealed that GM decreases in the left anterior cingulate and right supplementary motor area were positively correlated with addictive severity. Higher impulsivity was associated with smaller volume of the left anterior cingulate.

Discussion and conclusions

Our findings on BAs were mainly derived from internet gaming disorder (IGD) and pathological gambling (PG) studies, preliminarily suggesting that GM atrophy in the prefrontal and striatal areas might be a common structural biomarker of BAs.
The interplay of gaming disorder, gaming motivations, and the dark triad
Authors: Tang Wai Yen , Reer Felix , Quandt Thorsten
Published: April 2020

Background and aims

There is a considerable amount of research on the psychological antecedents and outcomes of gaming disorder. Although many studies have examined various personality traits or motivations as predictors in isolation, fewer studies have investigated the mediations between personality traits and motivations. Furthermore, the analyzed personality traits have been limited to a few core concepts, with the Big Five personality traits being a standard model in this context. However, more recently the dark triad of personality traits (Machiavellianism, narcissism, and psychopathy) has been found to be associated with various forms of problematic online behavior and usage, such as online gambling, yet little is known about gaming disorder. The current study examines the relationship of these dark personality traits to gaming disorder with three gaming motivations (achievement, social, and escapism) as mediators.

Method

The study uses an online survey of 1,502 German digital game users.

Results

Results indicate a fully mediated association for narcissism via escapism and partial mediation associations for Machiavellianism and psychopathy. Direct effects on gaming disorder were observed for Machiavellianism and psychopathy. Indirect effects by psychopathy were observed via escapism and social motivation, by narcissism via escapism, and by Machiavellianism via social motivation.

Discussion and conclusions

These findings contribute to the theoretical understanding of the mediation of gaming motivations and the dark triad personality traits' importance for gaming disorder.
Short-term effects of simulated microgravity on morphology and gene expression in human breast cancer cells
Authors: Strube F , Infanger M , Dietz C , Romswinkel A , Kraus A
Published: April 2020

Introduction

Microgravity has been shown to impose various effects on breast cancer cells. We exposed human breast cancer cells to simulated microgravity and studied morphology and alterations in gene expression.

Materials and methods

Human breast cancer cells were exposed to simulated microgravity in a random positioning machine (RPM) for 24 h. Morphology was observed under light microscopy, and gene alteration was studied by qPCR.

Results

After 24 h, formation of three-dimensional structures (spheroids) occurred. BRCA1 expression was significantly increased (1.9×, p < 0.05) in the adherent cells under simulated microgravity compared to the control. Expression of KRAS was significantly decreased (0.6×, p < 0.05) in the adherent cells compared to the control. VCAM1 was significantly upregulated (6.6×, 2.0×, p < 0.05 each) in the adherent cells under simulated microgravity and in the spheroids. VIM expression was significantly downregulated (0.45×, 0.44×, p < 0.05 each) in the adherent cells under simulated microgravity and in the spheroids. There was no significant alteration in the expression of MAPK1, MMP13, PTEN, and TP53.

Conclusions

Simulated microgravity induces spheroid formation in human breast cancer cells within 24 h and alters gene expression toward modified adhesion properties, enhanced cell repair, and phenotype preservation. Further insights into the underlying mechanisms could open up the way toward new therapies.
Pituitary adenylate cyclase activating polypeptide concentrations in the sheep mammary gland, milk, and in the lamb blood plasma after suckling
Authors: Pohóczky K. , Tamás A. , Reglődi D. , Kemény Á. , Helyes Zs. , Czeglédi L.
Published: April 2020

Pituitary adenylate cyclase activating polypeptide (PACAP) is involved in development and reproduction. We previously described elevated PACAP levels in the milk compared to the plasma, and the presence of its specific PAC1 receptor in the mammary gland. This study aimed to determine PACAP and vasoactive intestinal peptide (VIP) levels in female suckling lambs compared to ewe plasma and mammary gland, as well as their age-dependent alterations. mRNA expressions of PACAP, VIP, PAC1 receptor and brain-derived neurotrophic factor (BDNF) were quantified in the milk whey and mammary gland. PACAP38-like immunoreactivity (PACAP38-LI) was measured in plasma, milk whey and mammary gland by radioimmunoassay, VIP-LI by enzyme-linked immunoassay. PACAP38-LI was 5, 6 times higher in the milk compared to the plasma of lactating sheep. It significantly increased in the lamb plasma 1 h, but returned to basal level 2 h after suckling. However, VIP mRNA was not present in the mammary gland, we detected the VIP protein in the milk whey. BDNF mRNA significantly decreased with age to approximately 60% and 25% in the 3- and 10-year-old sheep respectively, compared to the 3-month-old lambs. No differences were found between mammary and jugular vein plasma PACAP and VIP concentrations, or during the daily cycle. We propose a rapid absorption of PACAP38 from the milk and/or its release in suckling lambs. PACAP accumulated in the milk might be synthesized in the mammary gland or secreted from the plasma of the mothers. PACAP is suggested to have differentiation/proliferation promoting and immunomodulatory effects in the newborns and/or a local function in the mammary gland.
Instillation of bradykinin into femoral artery elicits cardiorespiratory reflexes involving perivascular afferents in anesthetized rats
Authors: Singh Sanjeev K. , Mandal M. B. , Ravindran R.
Published: April 2020

The physiology of baroreceptors and chemoreceptors present in large blood vessels of the heart is well known in the regulation of cardiorespiratory functions. Since large blood vessels and peripheral blood vessels are of the same mesodermal origin, therefore, involvement of the latter in the regulation of cardiorespiratory system is expected. The role of perivascular nerves in mediating cardiorespiratory alterations produced after intra-arterial injection of a nociceptive agent (bradykinin) was examined in urethane-anesthetized male rats. Respiratory frequency, blood pressure, and heart rate were recorded for 30 min after the retrograde injection of bradykinin/saline into the femoral artery. In addition, paw edema was determined and water content was expressed as percentage of wet weight. Injection of bradykinin produced immediate tachypneic, hypotensive and bradycardiac responses of shorter latency (5–8 s) favoring the neural mechanisms involved in it. Injection of equi-volume of saline did not produce any responses and served as time-matched control. Paw edema was observed in the ipsilateral hind limb. Pretreatment with diclofenac sodium significantly attenuated the bradykinin-induced responses and also blocked the paw edema. Ipsilateral femoral and sciatic nerve sectioning attenuated bradykinin-induced responses significantly, indicating the origin of responses from the local vascular bed. Administration of bradykinin in the segment of an artery produced reflex cardiorespiratory changes by stimulating the perivascular nociceptors involving prostaglandins. This is a novel study exhibiting the role of peripheral blood vessels in the regulation of the cardiorespiratory system.