Elu, loodus, teadus ja tehnoloogia
Author(s): Samuel K. Lee, Mariangela Lisanti, Benjamin R. Safdi, Tracy R. Slatyer, and Wei Xue
New models show that neutron stars—and not dark matter—could be responsible for an excess of gamma rays from the Milky Way’s center.
[Phys. Rev. Lett. 116, 051103] Published Thu Feb 04, 2016
Author(s): Richard Bartels, Suraj Krishnamurthy, and Christoph Weniger
New models show that neutron stars—and not dark matter—could be responsible for an excess of gamma rays from the Milky Way’s center.
[Phys. Rev. Lett. 116, 051102] Published Thu Feb 04, 2016
ESA and the European Polar Board sign a Memorandum of Understanding
Operations image of the week: #SocialSpaceWA – ESA’s first-ever social media event down under – happens at the New Norcia deep-space tracking station, Western Australia, next week
Join us Friday, 5 February, at 10:00 CET for the ‘Earth from Space’ video programme. This week features a Sentinel-1A image of the Siljan crater in Sweden
The excess of gamma rays from the center of the Milky Way probably originates from rapidly rotating neutron stars and not from dark matter annihilation as previously claimed.
There are no large caverns inside Comet 67P/Churyumov-Gerasimenko. ESA’s Rosetta mission has made measurements that clearly demonstrate this, solving a long-standing mystery.
NASA’s Juno spacecraft performs maneuver. Jupiter is five months away.
With the launch of Sentinel-3A confirmed for 16 February, preparations for liftoff are charging full speed ahead. The tricky task of fuelling the satellite has now been ticked off the ‘to do list’ and the propulsion team is already decontaminating their equipment before returning home.
Author(s): K. Kisamori et al.Evidence that the four-neutron system known as the tetraneutron exists as a resonance has been uncovered in an experiment at the RIKEN Radioactive Ion Beam Factory.[Phys. Rev. Lett. 116, 052501] Published Wed Feb 03, 2016
Results confirm that more opaque areas in Saturn’s rings do not necessarily contain more material.
Technology image of the week: a commercial forest seen through the ‘eyes’ of a 3D laser scanning system
The forgotten history of de Broglie waves as themselves artifacts of a Lorentz transform, not
physical lengths and frequencies to be transformed, causes confusion for students and others. In
this paper the de Broglie wavelength is derived and depende…
In this paper, we present a simple spreadsheet based simulation activity that can be performed by
students at the undergraduate level. This simulation is implemented in free open source software
(FOSS) LibreOffice Calc, which is available for both Wi…
Throughout a general education course on sound and light aimed at music and art students, analogies
between subjective perceptions of objective properties of sound and light waves are a recurring
theme. Demonstrating that the pitch and loudness of mu…
Instead of solving ordinary differential equations (ODEs), the damped simple harmonic motion (SHM)
is surveyed qualitatively from basic mechanics and quantitatively by the instrumentality of a graph
of velocity against displacement. In this way, the …
This paper shows how it is possible to construct a very simple device for the measurement of
magnetic flux densities in an educational context. It is also shown how such a device can be
interfaced to a microcontroller with plotting-software to facili…
Use of mobile technology are widespread, particularly among the younger generation. There is a huge potential for utilizing such technology, particularly in lecture sessions with large number of students, serving as an interaction tool between the students and lecturer. The challenge is to identify adoption factors to ensure effective adoption of the technology to promote interactivity between students and lecturer in the classroom. This paper aims to examine factors supporting use of mobile wireless technology during lectures to promote interactivity between students and lecturers in Malaysia’s higher education institutions. Survey involving higher education students in Malaysia was conducted with a sample size of 302. Factor analysis results identified five factors: independent variables System Usefulness (SU), User System Perception (USP), User Uncertainty Avoidance (UUA), System and Information Quality (SIQ), and dependent variable Mobile Wireless Technology Adoption for Interactive Lectures (MWT_AIL). All independent variables are positively associated to MWT_AIL, with UUA and SIQ having higher level of significance compared to SU and USP. Respondents were selected from higher learning institutions from urban areas in Malaysia. Therefore results obtained are not representative of the entire higher education landscape in Malaysia and future studies are warranted to include higher learning institutions located in rural areas. It is hoped that findings from this study will serve as a catalyst for future researches to be conducted in this area, particularly among higher education researchers seeking ways to utilize technology effectively to enhance the learning experiences of the students in the classroom.
The purpose of this study was to identify the relationship between the psychological variables and online behavioral patterns of students, collected through a Learning Management System (LMS). Test was attempted of a structural equation model representing the relationships among Time and Study Environment Management (TSEM), one of the sub-constructs of MSLQ, influencing a set of time-related online log variables: login frequency, login regularity, and total login time. Data were collected from 188 college students in a Korean university. Employing structural equation modeling, a hypothesized model was tested for measuring the model fit. The results presented a criterion validity of online log variables to estimate their time management. The structural model including TSEM, online variable, and final score with a moderate fit indicated that learners’ time related online behavior mediates their psychological functions and their learning outcome. Based on the results, the final discussion includes the recommendations for further study and the meaningfulness in regard to the expantion of Learning Analtyics for Performance and Action (LAPA) model.
The blog as a type of social software has been used in education for several years, and its positive effect in the field has been asserted in many studies. This study presents the factors of participants and blogs that predict blogging activeness durin…
Students’ performance and behavior in online learning environment is associated with their readiness to opt digital learning approach. We in this research investigated distance learners’ emotional intelligence as a determinant of their readiness for online learning. 432 learners enrolled in correspondence based distance learning programs participated in the study. Wong and Law emotional intelligence scale (WLEIS) and online learning readiness scale (OLRS) were adapted with some modifications to collected the required data. Pearson correlation and multiple regression analysis were done to achieve the research objectives. The findings illustrate that emotional intelligence has a large size effect on sampled students’ readiness for online learning.
A course design question for self-paced courses includes whether or not technological measures should be used in course design to force students to follow the sequence intended by the course author. This study examined learner behavior to understand wh…
In order for higher education institutions, which implements blended and/or online learning to remain competitive and innovative it needs to keep up with the cutting edge technological and educational advances. This task is usually very difficult, keeping in mind the budget constraints that many institutions have. This usually implies that existing open source solutions have to be used and adapted to individual needs of each institution. Keeping up with the current technological advances often brings not only financial challenges, but also transitional challenges that may put at risk learning quality and reputation of the institution, as well as performance of students. This work describes the features of the system, results and challenges of transitioning to e-learning system that displays learning materials through sequence of reusable learning objects (LOs) from the system that does not have these capabilities. The goal of such system is to increase reusability of learning content, and moreover, to increase online interactivity and communication between the instructor and students. Findings of this work reveal advantages, disadvantages and potential obstacle of implementation e-learning system with LOs and give an overview of suggestions for implementation improvements. These suggestions are given based on evaluation of implementation of new e-learning system with LOs, after the transition from the traditional e-learning system. Furthermore, based on the research of existing methodologies in the field of information systems, and the results of this research, this work proposes methodology for transferring into e-learning system with LOs.
On the one hand, a growing amount of research discusses support for improving online collaborative learning quality, and many indicators are focused to assess its success. On the other hand, thinkLets for designing reputable and valuable collaborative processes have been developed for more than ten years. However, few studies try to apply thinkLets to online collaborative learning. This paper introduces thinkLets to online collaborative learning and experimentally tests its effectiveness with participants responces on their satisfaction. Yield Shift Theory (YST), a causal theory explaining inner satisfaction, is adopted. In the experiment, 113 students from Universities in Beijing, China are chosen as a sample. They were divided into two groups, collaborating online in a simulated class. Then, YST in student groups under online collaborative learning is validated, comparison study of online collaborative learning with and without thinkLets is implemented and satisfaction response of participants are analyzed. As a result of this comparison, YST is proved applicable in this context, and satisfaction is higher in online collaborative learning with thinkLets.
This study aimed to investigate the effectiveness of two different teaching methods on learning effectiveness. OpenCourseWare was integrated into the flipped classroom model (experimental group) and distance learning (control group). Learning effectiveness encompassed learning achievement, teacher-student interactions, and learning satisfaction. The experimental method was supplemented with qualitative interviews. Overall, 181 freshmen taking a course on physics were allowed to choose their own class based on their preferred teaching method (experimental or control group). The findings indicated that learners in the experimental group scored higher for learning achievement. When selecting a teaching method, if sufficient resources are available, it is suggested that teachers provide learners with the combination of OCW and flipped classroom. Although there was no significant between-group difference in terms of teacher-student interactions and learning satisfaction, the interactions in the flipped classroom had positive effect on students’ learning achievement. The use of the flipped classroom model allows for adequate teacher-student interactions, as teachers can provide guidance and assistance to students in person, while there are greater opportunities for collaborative learning among learners. In addition, since the flipped classroom model emphasizes the process of learning rather than its outcomes, information technology tools should be used to keep detailed records and follow the learning process in order to assess various aspects of the learners’ growth. The results of this study can serve as a reference for future studies on the flipped classroom model and OpenCourseWare, as well as for teachers and researchers in related fields.
The Effective Classroom Interactions (ECI) online courses were designed to provide an engaging, effective and scalable approach to enhancing early childhood teachers’ use of classroom practices that impact children’s school readiness. The created courses included several versions aimed at testing whether or not certain design aspects could increase participation and subsequent learning outcomes. The purpose of this study was to examine the extent to which early childhood teachers accessed the courses and varied in their a) participation in the core course content and b) optional discussion board as a result of the course experience they were assigned to as well as individual characteristics that may be associated with participation. Findings indicated that early childhood teachers accessed the course often on nights and weekends and reported high levels of satisfaction with their experience. Both persistence in the ECI courses and overall completion of activities were higher than those reported in other studies of online learning. Whether or not the participant was in the course that had regular interactions with the instructor, comfort with technology and took the course for credit consistently predicted participation, but not always in expected ways. Implications for exploring online learning as a feasible option for early childhood educators are discussed.
Handheld devices are widely applied to support open and distributed learning, where students are diverse. On the other hand, customization and personalization can be applied to accommodate students’ diversities. However, paucity of research compares the effects of customization and personalization in the context of handheld devices. To this end, we developed a customized digital learning system (CDLS) and personalized digital learning system (PDLS), which were implemented on the handheld devices and tailored to the needs of students with diverse cognitive styles. Furthermore, we conducted two empirical studies to examine the effects of cognitive styles on the use of the CDLS and PDLS. More specifically, Study 1 identified the preferences of each cognitive style group, which were employed to develop the PDLS in Study 2, which investigated how students with different cognitive styles react to the CDLS and the PDLS. The results from these two studies showed that student in the CDLS and those in the PDLS obtained similar task scores and post-test scores. However, Serialists with the PDLS could more efficiently complete the tasks than those with CDLS. Additionally, Holists more positively perceived the PDLS than Serialists.
This study investigated interactive effects of navigation and offline comprehension skill on digital reading performance. As indicators of navigation relevant page selection and irrelevant page selection were considered. In 533 Spanish high school stud…
Using in-class questions is an efficient instructional strategy to keep abreast of the state of student learning in a class. Some studies have found that discussing in-class questions in synchronous learning is helpful. These studies demonstrated that …
A recent study from NASA’s Cassini mission proves that, in the mysterious and beautiful rings of Saturn, appearances can be deceiving.
The first flight of NASA’s new rocket, the Space Launch System (SLS), will carry 13 low-cost CubeSats to test innovative ideas along with an uncrewed Orion spacecraft in 2018.
A small asteroid that two years ago flew past Earth at a comfortable distance of about 1.3 million miles (2 million kilometers) will safely fly by our planet again in a few weeks, though this time it may be much closer.
Human spaceflight and robotic operations image of the week: the capital of the United Kingdom at midnight on a Saturday seen from 400 km above
The Pictor A Galaxy contains a supermassive black hole at its center, and a huge amount of gravitational energy is released as material swirls toward the event horizon.
Groundhog Day is one of the four so-called cross-quarter days, which mark the midpoints between the solstices and equinoxes.
Europe’s ninth and tenth Galileo satellites have started broadcasting working navigation messages.
2 February marks World Wetlands Day. Discover some of Earth’s most important wetlands seen from 800 km high
We have developed and evaluated a quantum interactive learning tutorial (QuILT) on a Mach?Zehnder
interferometer with single photons to expose upper-level students in quantum mechanics courses to
contemporary quantum optics applications. The QuILT st…
Hodographs for the Kepler problem are circles. This fact, known for almost two centuries, still
provides the simplest path to derive the Kepler first law. Through Feynman?s ?lost lecture?, this
derivation has now reached a wider audience. Here we loo…
Students often find astronomy and astrophysics to be most interesting and exciting, but the Universe
is difficult to access using only one’s eyes or simple equipment available at different educational
settings. To open up the Universe and enhance l…
Semiconductor materials are at the core of electronics. Most electronic devices are made of
semiconductors. The operation of these components is well described by quantum physics which is
often a difficult concept for students to understand. One of t…
We have developed and evaluated a quantum interactive learning tutorial (QuILT) on a Mach–Zehnder
interferometer with single photons to expose upper-level students in quantum mechanics courses to
contemporary quantum optics applications. The QuILT …
Hodographs for the Kepler problem are circles. This fact, known for almost two centuries, still
provides the simplest path to derive the Kepler first law. Through Feynman’s ‘lost lecture’, this
derivation has now reached a wider audience. Here …
Troy High School triumphed over 23 other teams at the National Science Bowl regional competition held at JPL on Jan. 30.
Author(s): Andreas Hilfinger, Thomas M. Norman, Glenn Vinnicombe, and Johan PaulssonBiochemical networks are often poorly characterized, but researchers can still derive limits on the level of the random variations or noise in different network compone…
Author(s): Kinjalk Lochan and T. PadmanabhanQuantum matter falling into a semiclassical black hole leaves an imprint on future Hawking radiation. The resulting black hole entropy will be much smaller than the area of the event horizon.[Phys. Rev. Lett….
Author(s): S. Middey, D. Meyers, D. Doennig, M. Kareev, X. Liu, Y. Cao, Zhenzhong Yang, Jinan Shi, Lin Gu, P. J. Ryan, R. Pentcheva, J. W. Freeland, and J. Chakhalian
Geometrical engineering of nickelate-based heterostructures can result in artificial graphene-like Mott crystals with antiferromagnetic correlations, structures that are not seen in bulk nickelates.
[Phys. Rev. Lett. 116, 056801] Published Mon Feb 01, 2016
Author(s): Abhay Ashtekar, Béatrice Bonga, and Aruna Kesavan
The mathematical framework used to describe gravitational waves is extended to incorporate the effect of a positive cosmological constant for the first time.
[Phys. Rev. Lett. 116, 051101] Published Mon Feb 01, 2016
Author(s): M. B. Jungfleisch, W. Zhang, J. Sklenar, J. Ding, W. Jiang, H. Chang, F. Y. Fradin, J. E. Pearson, J. B. Ketterson, V. Novosad, M. Wu, and A. Hoffmann
A spin-torque-driven ferromagnetic resonance in magnetic insulators is spatially mapped showing a localized spin-wave structure.
[Phys. Rev. Lett. 116, 057601] Published Mon Feb 01, 2016
Author(s): Mihai D. Vidrighin, Oscar Dahlsten, Marco Barbieri, M. S. Kim, Vlatko Vedral, and Ian A. Walmsley
Information derived from microscopic measurements of thermal states made using a few photons is used to extract macroscopic work.
[Phys. Rev. Lett. 116, 050401] Published Mon Feb 01, 2016
ESA is teaming up with the organisers of Asteroid Day 2016, scheduled for 30 June
Lifeforms taken from the most Mars-like place on Earth managed to survive the harsh conditions of space.
Space science image of the week: A fragile-looking rectangular shape is revealed to be a dying star
The ‘ Guide to the Expression of Uncertainty in Measurement ’ (GUM) has been in use for more than 20
years, serving its purposes worldwide at all levels of metrology, from scientific to industrial and
commercial applications. However, the GUM pre…
Watch the replay of the launch of the European Data Relay System’s first laser node from Baikonur, Kazakhstan on 29 January at 22:20 GMT
Watch the replay of the launch of the European Data Relay System’s first laser node from Baikonur, Kazakhstan on 29 January at 22:20 GMT
The European Data Relay System’s first laser terminal has reached space aboard its host satellite and is now under way to its final operating position
The first laser node of the European Data Relay System lifted off from Baikonur, Kazakhstan atop a Proton rocket on 29 January at 22:20 GMT
Researchers have developed a way to make maps of natural disaster damage using remote sensing technology.
The latest self-portrait from NASA’s Curiosity Mars rover shows the car-size mobile laboratory beside a dark dune where it has been scooping and sieving samples of sand.
A colorful new animation shows a simulated flight over the surface of dwarf planet Ceres, based on images from NASA’s Dawn spacecraft.
Our week through the lens: 25-29 January 2016
Author(s): Hongchuan Shen, Peng Tan, and Lei XuSteel spheres placed on a square grid, connected by springs, and individually driven by motors are used to investigate the vibrational modes of a nonequilibrium system.[Phys. Rev. Lett. 116, 048302] Publis…
A new map shows exposed water ice to be considerably more widespread across Pluto’s surface than was previously known.
The key to reconstructing the giant impact was a chemical signature revealed in the rocks’ oxygen atoms.
Earth observation image of the week: a Sentinel-2A image of Sierra Leone, also featured on the Earth from Space video programme
The cosmological constant regained the attention of the scientific community following the recent
discovery of the accelerated expansion of the Universe. Consequently, interest in the subject
increased amongst the public such that it now often appear…
The aim of this paper is to make a determination of Hubble?s constant from the experimental data on
the magnitude and redshift of supernovae. We proposed a very simple approach that could also be very
useful from a didactic point of view.
In this note we explicitly show how the Lorentz transformations can be derived by demanding form
invariance of the d’Alembert operator in inertial reference frames.
Snell’s law states that the quantity ##IMG##
[http://ej.iop.org/images/0143-0807/37/2/025301/ejpaa12c8ieqn3.gif] {$nmathrm{sin}theta $} is
unchanged in refraction of light passing from one medium to another. We inquire whether this is true
in th…
The cosmological constant regained the attention of the scientific community following the recent
discovery of the accelerated expansion of the Universe. Consequently, interest in the subject
increased amongst the public such that it now often appear…
The use of an infrared sensor as a new alternative to measure position as a function of time in
kinematic experiments was investigated using a microcontroller as the data acquisition and control
device. These are versatile sensors that offer advantag…
Coupled systems subject to dissipation exhibit two different regimes known as weak coupling and
strong coupling. Two damped coupled harmonic oscillators (CHOs) constitute a model system where the
key features of weak and strong coupling can be identi…
The aim of this paper is to make a determination of Hubble’s constant from the experimental data on
the magnitude and redshift of supernovae. We proposed a very simple approach that could also be very
useful from a didactic point of view.
A simple experiment for measuring the surface tension coefficient is proposed, which is well suited
for teaching and learning the behavior of liquids in typical student laboratories. It is based on
the pull-off method and the dynamometer used is the …
Author(s): Manoj Kaplinghat, Sean Tulin, and Hai-Bo YuA new model has allowed researchers to test a theory for why the centers of dark matter halos are less dense than expected.[Phys. Rev. Lett. 116, 041302] Published Thu Jan 28, 2016
Operations image of the week: Mission control teams begin intensive simulation training for the launch of Sentinel-1B, part of Europe’s Copernicus programme
Join us Friday, 29 January, at 10:00 CET for the ‘Earth from Space’ video programme. Ahead of World Wetlands Day this week’s video features the Sierra Leone River Estuary
Though hundreds of enormous high-velocity gas clouds whiz around the outskirts of our galaxy, this so-called “Smith Cloud” is unique because its trajectory is well known.
Globular clusters can somehow bear second or even third sets of thousands of sibling stars.
Watch the launch of ESA’s first European Data Relay System (EDRS) laser node live on 29 January. Streaming starts 20 minutes before liftoff, with launch expected at 22:20 GMT
This block of martian terrain, etched with an intricate pattern of landslides and wind-blown dunes, is a small segment of a vast labyrinth of valleys, fractures and plateaus.
An Ariane 5 last night delivered telecom satellite Intelsat-29e into its planned orbit. Liftoff of Ariane flight VA228 occurred on 27 January at 23:20 GMT (20:20 local time, 00:20 CET on 28 January) from Europe’s Spaceport in Kourou, French Guiana.
In just two 10-minute overflights, an airborne NASA synthetic aperture radar proved it could pinpoint areas of disturbance in Peru’s Nasca lines World Heritage Site.
NASA’s Jet Propulsion Laboratory in Pasadena, Calif., has selected four companies to conduct design studies for a solar-electric-propulsion-based spacecraft for the agency’s Asteroid Redirect Robotic Mission (ARRM).
Author(s): I. Boettcher, L. Bayha, D. Kedar, P. A. Murthy, M. Neidig, M. G. Ries, A. N. Wenz, G. Zürn, S. Jochim, and T. Enss
Two separate groups have extracted the thermodynamic equation of state for a two-dimensional gas of fermionic atoms, revealing its peculiar quantum features.
[Phys. Rev. Lett. 116, 045303] Published Wed Jan 27, 2016
Author(s): K. Fenech, P. Dyke, T. Peppler, M. G. Lingham, S. Hoinka, H. Hu, and C. J. Vale
Two separate groups have extracted the thermodynamic equation of state for a two-dimensional gas of fermionic atoms, revealing its peculiar quantum features.
[Phys. Rev. Lett. 116, 045302] Published Wed Jan 27, 2016
Author(s): A. Lim, W. M. C. Foulkes, A. P. Horsfield, D. R. Mason, A. Schleife, E. W. Draeger, and A. A. Correa
Ab initio simulations of electronic excitations produced when a semiconductor experiences a large perturbation show a new regime in electron-ion energy exchange whereby a defect state carries electrons across the band gap.
[Phys. Rev. Lett. 116, 043201] Published Wed Jan 27, 2016
Sixteen telescopes from space and the ground revealed a gorging black hole in a galaxy 900 million light-years from Earth.
Technology image of the week: the Mercury Planetary Orbiter of the BepiColombo mission standing high above the floor of its test chamber
NASA’s PRISM instrument is part of a flying lab that is studying the Southern Ocean’s appetite for carbon dioxide.
In 1801, when an astronomer pointed his telescope at a seemingly star-like point of light, he probably had no idea a robotic emissary from Earth would one day be sent there.
Author(s): P. Jamonneau, G. Hétet, A. Dréau, J.-F. Roch, and V. Jacques
A dark state – a state that cannot emit or absorb photons – can be created by the hyperfine coupling of the electron spin of a single nitrogen-vacancy defect to a nearby 13C nuclear spin.
[Phys. Rev. Lett. 116, 043603] Published Tue Jan 26, 2016
Author(s): Huangjun ZhuUnderlying symmetries can be used to elucidate the structure and properties of the discrete version of the Wigner quasi-probability distribution function in phase space.[Phys. Rev. Lett. 116, 040501] Published Tue Jan 26, 2016
Author(s): F. Lecocq, J. B. Clark, R. W. Simmonds, J. Aumentado, and J. D. Teufel
A new device converts the frequency of a photon using the vibrations in a mechanical oscillator.
[Phys. Rev. Lett. 116, 043601] Published Tue Jan 26, 2016
Author(s): M. R. Delbecq, T. Nakajima, P. Stano, T. Otsuka, S. Amaha, J. Yoneda, K. Takeda, G. Allison, A. Ludwig, A. D. Wieck, and S. Tarucha<br/>We extract the phase coherence of a qubit defined by singlet and triplet electronic states in a gated GaAs triple quantum dot, measuring on time scales much shorter than the decorrelation time of the environmental noise. In this nonergodic regime, we observe that the coherence is boosted and several…<br/><img src="//d22izw7byeupn1.cloudfront.net/journals/PRL/key_images/10.1103/PhysRevLett.116.046802.png" width="200" height="100"><br/>[Phys. Rev. Lett. 116, 046802] Published Tue Jan 26, 2016
A new study suggests that the internal structure of a cluster is linked to the dark matter environment surrounding it.
Once thought to be a free-floating planet, astronomers have now discovered it orbits its star only once every 900,000 years.