95 research outputs found
Enhancing Historical Reasoning: A Strategy Including Formative Assessment with Systematic Continuous Feedback
Learning History promotes students’ reasoning. According to Van Drie & Van Boxtel (2008), historical reasoning involves six elements: substantive concepts, metaconcepts, asking historical questions, using sources, contextualization, and argumentation. Although there are didactic strategies that promote historical reasoning, these do not include systematic continuous feedback using rubrics, which can be useful both in assessing and promoting students’ progress and progression of ideas on metaconcepts. This study described the development of the six historical reasoning elements in a strategy that included formative assessment for K8 students. A case study was carried out in Mexico City: four teams of three students were formed according to their knowledge of history, with a single History teacher providing continuous systematic feedback on metaconcepts by using graded rubrics. Results showed that the six historical reasoning elements were developed in different ways and suggested possible methods for use in future didactics
Trends in application of NIR and hyperspectral imaging for food authentication
Food fraud can cause damage to consumer health and affect their confidence, destroy brands and generate large economic losses in the industry. Food authenticity allows to identify if food composition, geographical origin, genetic variety and farming system corresponds to what has been declared on the label. Although there are currently standardized methods to identify certain adulterants, the complexity of the food, the complexity of the supply chain and the appearance of new adulterants require the continuous development of analytical techniques to detect food fraud. NIR and Hyperspectral imaging (HSI) in tandem with chemometrics are non-destructive, non-invasive and accurate techniques for food authentication. This review focuses on NIR and HIS approaches to food authentication, including adulteration by substitution, geographical origin and farming system. In this context, the advances in NIR and HSI approaches reported since 2014 are discussed regarding their potential use in food authentication. Both techniques have shown to have efficiency, precision and selectivity to detect adulterants and identify geographic origin, genetic variety and farming system. Portability and remote access are shown as the next step for the industrialization of NIR and HSI devices
Exposición a la violencia y conducta prosocial: el papel mediador de la funcionalidad familiar en adolescentes de Nuevo Chimbote
La presente investigación tuvo como finalidad, determinar el efecto predictivo del
funcionamiento familiar y la exposición a la violencia sobre la conducta prosocial en
adolescentes de Nuevo Chimbote. La población fue conformada por 353, cuyas
edades oscilan entre los 13 a 18 años. Para la medición de las variables se hizo
uso del Cuestionario de Exposición a la Violencia (CEV), Escala de Conducta
Prosocial (ECP) y el Cuestionario de Percepción de la funcionalidad Familiar (FFSIL).
En los resultados se evidenció que la funcionalidad familiar media la
exposición a la violencia en casa con un efecto indirecto negativo sobre el
comportamiento prosocial (EI=-.185; p=.000) y con efecto indirecto positivo en la
variable dependiente (EI=.047; p=0.20), estos datos contribuyen a formar un
precedente, de tal manera que genera mayor conocimiento con respecto a la
influencia que tiene la familia sobre la conducta prosocial
IFA and PIFA Size Reduction by Using a Stub Loading
A proposed technique for size reduction of a conventional inverted-F antenna (IFA) and a planar inverted-F antenna (PIFA) by employing a reactive load generated by a short-circuited stub is presented. The reduction factor of both antennas is around 30%, and the main parameters of the devices are preserved, including a fractional bandwidth of 4% and a gain of −2 dB. Both antennas operate around 1.5 GHz
Mutual Coupling Reduction of Two 2x1 Triangular-Patch Antenna Array Using a Single Neutralization Line for MIMO Applications
In this paper, a novel structure of two interlaced antenna arrays for MIMO applications is presented. It consists of two 2x1 triangular patch array antennas, which have all elements separated by a short distance among them (0.22λ0), where mutual coupling can be very poor (S21 = –7.81 dB). To overcome such weakness, a simple and efficient method is used: one neutralization line (NL) is introduced to increase the decoupling between both ports, reaching up to –29 dB at the central frequency, and below –20 dB over a large bandwidth. The whole MIMO antenna array has dimensions of 1.56λ0 × 0.3λ0 and has a gain of 9.11 dBi. Its diversity parameters describe it as a useful radiator for MIMO communications systems
Knowledge Graphs Evolution and Preservation -- A Technical Report from ISWS 2019
One of the grand challenges discussed during the Dagstuhl Seminar "Knowledge
Graphs: New Directions for Knowledge Representation on the Semantic Web" and
described in its report is that of a: "Public FAIR Knowledge Graph of
Everything: We increasingly see the creation of knowledge graphs that capture
information about the entirety of a class of entities. [...] This grand
challenge extends this further by asking if we can create a knowledge graph of
"everything" ranging from common sense concepts to location based entities.
This knowledge graph should be "open to the public" in a FAIR manner
democratizing this mass amount of knowledge." Although linked open data (LOD)
is one knowledge graph, it is the closest realisation (and probably the only
one) to a public FAIR Knowledge Graph (KG) of everything. Surely, LOD provides
a unique testbed for experimenting and evaluating research hypotheses on open
and FAIR KG. One of the most neglected FAIR issues about KGs is their ongoing
evolution and long term preservation. We want to investigate this problem, that
is to understand what preserving and supporting the evolution of KGs means and
how these problems can be addressed. Clearly, the problem can be approached
from different perspectives and may require the development of different
approaches, including new theories, ontologies, metrics, strategies,
procedures, etc. This document reports a collaborative effort performed by 9
teams of students, each guided by a senior researcher as their mentor,
attending the International Semantic Web Research School (ISWS 2019). Each team
provides a different perspective to the problem of knowledge graph evolution
substantiated by a set of research questions as the main subject of their
investigation. In addition, they provide their working definition for KG
preservation and evolution
A large topographic feature on the surface of the trans-Neptunian object (307261) 2002 MS measured from stellar occultations
This work aims at constraining the size, shape, and geometric albedo of the
dwarf planet candidate 2002 MS4 through the analysis of nine stellar
occultation events. Using multichord detection, we also studied the object's
topography by analyzing the obtained limb and the residuals between observed
chords and the best-fitted ellipse. We predicted and organized the
observational campaigns of nine stellar occultations by 2002 MS4 between 2019
and 2022, resulting in two single-chord events, four double-chord detections,
and three events with three to up to sixty-one positive chords. Using 13
selected chords from the 8 August 2020 event, we determined the global
elliptical limb of 2002 MS4. The best-fitted ellipse, combined with the
object's rotational information from the literature, constrains the object's
size, shape, and albedo. Additionally, we developed a new method to
characterize topography features on the object's limb. The global limb has a
semi-major axis of 412 10 km, a semi-minor axis of 385 17 km, and
the position angle of the minor axis is 121 16. From
this instantaneous limb, we obtained 2002 MS4's geometric albedo and the
projected area-equivalent diameter. Significant deviations from the fitted
ellipse in the northernmost limb are detected from multiple sites highlighting
three distinct topographic features: one 11 km depth depression followed by a
25 km height elevation next to a crater-like depression with an
extension of 322 39 km and 45.1 1.5 km deep. Our results present an
object that is 138 km smaller in diameter than derived from thermal
data, possibly indicating the presence of a so-far unknown satellite. However,
within the error bars, the geometric albedo in the V-band agrees with the
results published in the literature, even with the radiometric-derived albedo
MAGIC detection of GRB 201216C at z = 1.1
Gamma-ray bursts (GRBs) are explosive transient events occurring at cosmological distances, releasing a large amount of energy as electromagnetic radiation over several energy bands. We report the detection of the long GRB 201216C by the MAGIC telescopes. The source is located at z = 1.1 and thus it is the farthest one detected at very high energies. The emission above 70 GeV of GRB 201216C is modelled together with multiwavelength data within a synchrotron and synchrotron self-Compton (SSC) scenario. We find that SSC can explain the broad-band data well from the optical to the very-high-energy band. For the late-time radio data, a different component is needed to account for the observed emission. Differently from previous GRBs detected in the very-high-energy range, the model for GRB 201216C strongly favours a wind-like medium. The model parameters have values similar to those found in past studies of the afterglows of GRBs detected up to GeV energies
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