9,777 research outputs found
The nuclear track detector CR39: results from different experiments
The nuclear track detector CR39 was calibrated with different ions of
different energies. Due to the low detection threshold (Z/beta~6e) and the good
charge resolution (sigma_Z ~ 0.2e for 6e < Z/beta <83e with 2 measurements),
the detector was used for different purposes: (i) fragmentation of high and
medium energy ions; (ii) search for magnetic monopoles, nuclearites,
strangelets and Q-balls in the cosmic radiation.Comment: 4 pages, 5 eps figures. Invited talk at the 11th Topical Seminar on
Innovative Particle and Radiation Detectors, Siena, Italy, 1-4 October 200
Shotgun ion mobility mass spectrometry sequencing of heparan sulfate saccharides
Despite evident regulatory roles of heparan sulfate (HS) saccharides in numerous biological processes, definitive information on the bioactive sequences of these polymers is lacking, with only a handful of natural structures sequenced to date. Here, we develop a “Shotgun” Ion Mobility Mass Spectrometry Sequencing (SIMMS2) method in which intact HS saccharides are dissociated in an ion mobility mass spectrometer and collision cross section values of fragments measured. Matching of data for intact and fragment ions against known values for 36 fully defined HS saccharide structures (from di- to decasaccharides) permits unambiguous sequence determination of validated standards and unknown natural saccharides, notably including variants with 3O-sulfate groups. SIMMS2 analysis of two fibroblast growth factor-inhibiting hexasaccharides identified from a HS oligosaccharide library screen demonstrates that the approach allows elucidation of structure-activity relationships. SIMMS2 thus overcomes the bottleneck for decoding the informational content of functional HS motifs which is crucial for their future biomedical exploitation
Search for Intermediate Mass Magnetic Monopoles and Nuclearites with the SLIM experiment
SLIM is a large area experiment (440 m2) installed at the Chacaltaya cosmic
ray laboratory since 2001, and about 100 m2 at Koksil, Himalaya, since 2003. It
is devoted to the search for intermediate mass magnetic monopoles (107-1013
GeV/c2) and nuclearites in the cosmic radiation using stacks of CR39 and
Makrofol nuclear track detectors. In four years of operation it will reach a
sensitivity to a flux of about 10-15 cm-2 s-1 sr-1. We present the results of
the calibration of CR39 and Makrofol and the analysis of a first sample of the
exposed detector.Comment: Presented at the 22nd ICNTS, Barcelona 200
Educational Uses of Augmented Reality (AR): Experiences in Educational Science
Augmented Reality (AR) is an emerging technology that is gaining greater influence on teaching every day. AR, together with mobile technology, is defined as one of the most efficient pairs for supporting significant and ubiquitous learning. Purpose of the study: the Instructional Material Motivational Survey (IMMS), by Keller, was used to determine the degree of motivation possessed by the Pedagogy students on the utilization of the notes enriched with AR in the classroom, available for their didactic use through mobile devices. Methods: through an app designed for the courses Education Technology (ET) and Information and Communication Technologies (ICT) Applied to Education, the motivation gained when participating in this experience, and how it influences the improvement of academic performance, was evaluated. Results and conclusions: the most notable main result was finding a strong relationship between the motivation of the students when using the enriched notes and the increase of performance in the academic subject where it was used. Likewise, it was proved that the use of Augmented Reality benefited the learning process itself
Nuclear Track Detectors. Searches for Exotic Particles
We used Nuclear Track Detectors (NTD) CR39 and Makrofol for many purposes: i)
Exposures at the SPS and at lower energy accelerator heavy ion beams for
calibration purposes and for fragmentation studies. ii) Searches for GUT and
Intermediate Mass Magnetic Monopoles (IMM), nuclearites, Q-balls and
strangelets in the cosmic radiation. The MACRO experiment in the Gran Sasso
underground lab, with ~1000 m^2 of CR39 detectors (plus scintillators and
streamer tubes), established an upper limit for superheavy GUT poles at the
level of 1.4x10^-16 cm^-2 s^-1 sr^-1 for 4x10^-5 <beta<1. The SLIM experiment
at the high altitude Chacaltaya lab (5230 m a.s.l.), using 427 m^2 of CR39
detectors exposed for 4.22 y, gave an upper limit for IMMs of ~1.3x10^-15 cm^-2
s^-1 sr^-1. The experiments yielded interesting upper limits also on the fluxes
of the other mentioned exotic particles. iii) Environmental studies, radiation
monitoring, neutron dosimetry.Comment: Talk given at "New Trends In High-Energy Physics" (experiment,
phenomenology, theory) Yalta, Crimea, Ukraine, September 27-October 4, 200
Search for massive rare particles with the SLIM experiment
The SLIM experiment is a large array of nuclear track detectors located at
the Chacaltaya High Altitude Laboratory (5260 m a.s.l.). The preliminary
results from the analysis of ~383 m^2 exposed for 4.07 y are here reported. The
detector is sensitive to Intermediate Mass Magnetic Monopoles, 10^5 < M_M <
10^12 GeV, and to SQM nuggets and Q-balls, which are possible Dark Matter
candidates.Comment: 4 pages, 5 EPS figures. Talk given at the 10th ICATPP Conference on
Astroparticle, Particle, Space Physics, Detectors and Medical Physics
Applications, Como, Italy, 8-12 October 200
Preferences of Indian Meal Moth Larvae for Different Dog Foods
Indian meal moths (IMM), Plodiainterpuntella, are persistent pests to our foods (Fasulo et al.1998; Plunkett’s Pest Control 2018). When IMMs infest a a food product the resulting value loss is the result of contamination by larvae that leave droppings and silken webs in grain and grain products (Jacob and Calvin 2001). The IMM is an important pest of high-value dog foods and the grain components of these food may influence their infestation. Experiments were conducted with eggs of the IMM to determine if moth larvae would choose and infest the grain-based dog food in comparison to dog foods with a higher meat content. IMM laboratory rearing diet was included for comparison. No-choice and choice tests confirmed the IMM diet to be the most preferred and best for larval development. Forced infestation of 50 IMM eggs on the four different dog foods found difference among them. In two-choice test that require newly hatched larvae to walk to and infest either lab diet or a dog food, the highest proportion of larvae selecting any of the dog foods was on product C, which was a medium quality, grain-free food. These results suggest that IMM infestations in warehouses or consumer’s homes could be prevalent on some dog foods more than others
The motivation of technological scenarios in augmented reality (AR): results of different experiments
Augmented Reality (AR) is an emergent technology that is acquiring more and more
relevance in teaching every day. Together with mobile technology, this combination arises as
one of the most effective binomials to support significant and ubiquitous learning. Nevertheless,
this binomial can only prove valid if the student is motivated to use it during the learning process.
An attempt was made through the implementation of Keller’s Instructional Material Motivational
Survey model o determine the degree of motivation of Pedagogy, Medicine and Art students from
the University of Seville for using AR-enriched notes available by means of mobile devices in the
classroom. Three applications designed for the subjects of Educational Technology, Anatomy and Art
served to assess it positively in terms of the motivation raised by the participation in the experiment,
as well as regarding academic performance improvement. It can additionally be stated that our main
finding was a link between students’ motivation to use the enriched notes and the performance
obtained in the subject in which they use them. Evidence was also found that the utilization of
Augmented Reality benefits the learning process
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