4,272 research outputs found
A binocular-type atmospheric interaction generating sequential exotic features
A cosmic-ray induced nuclear event is presented, which is of clear binocular-type and contains several exotic features through its passage in the atmosphere and the emulsion chamber
A halo event created at 200 m above the Chacaltaya emulsion chamber
The results of analysis on a cosmic-ray induced nuclear event with the total visible energy approx. = 1300 TeV which is characterized by the central (halo) part of a strong energy concentration and the outer part of a large lateral spread are presented. The event (named as P06) was detected in the 18th two-storied emulsion chamber exposed at Chacaltaya by Brasil-Japan Collaboration. As the nuclear emulsion plates were inserted at every layer of the concerned blocks in the upper and the lower chambers together with RR- and N-type X-ray films, it is possible to study the details of the event. Some results on P06 have already been reported 1 based on the general measurement of opacity on N-type X-ray films: (1) the total energy of halo is approx. = 1000 TeV; (2) the shower transition reaches its maximum at approx. 16 cu; and (3) the radius of halo is 6.5 mm (at the level of 10 to the 6th power electrons/sq.cm.). The results in more details will be described
Atmospheric interactions detected in both the upper and the lower chambers at Chacaltaya
The cosmic ray interactions in the energy region 10 to the 13th power to 10 to the 17th power eV were studied by emulsion chambers exposed at Chacaltaya, 5220 m above sea-level. The chambers have a two-storied structure, and the events observed in both chambers give important informations on these phenomena. The first Centauro event was detected as a small shower at the bottom of the upper chamber and as a big fraction of energy deposit in the lower chamber, which indicates a high contribution of hadronic showers. Results of the events with continuation in the rather low energy region are described
Linearly independent pure-state decomposition and quantum state discrimination
We put the pure-state decomposition mathematical property of a mixed state to
a physical test. We begin by characterizing all the possible decompositions of
a rank-two mixed state by means of the complex overlap between two involved
states. The physical test proposes a scheme of quantum state recognition of one
of the two linearly independent states which arise from the decomposition. We
find that the two states associated with the balanced pure-state decomposition
have the smaller overlap modulus and therefore the smallest probability of
being discriminated conclusively, while in the nonconclusive scheme they have
the highest probability of having an error. In addition, we design an
experimental scheme which allows to discriminate conclusively and optimally two
nonorthogonal states prepared with different a priori probabilities. Thus, we
propose a physical implementation for this linearly independent pure-state
decomposition and state discrimination test by using twin photons generated in
the process of spontaneous parametric down conversion. The information-state is
encoded in one photon polarization state whereas the second single-photon is
used for heralded detection.Comment: 6 pages, 5 figures, Submitted to Phys. Rev.
From laboratory manipulations to Earth system models: scaling calcification impacts of ocean acidification
The observed variation in the calcification responses of coccolithophores to changes in carbonate chemistry paints a highly incoherent picture, particularly for the most commonly cultured "species", <i>Emiliania huxleyi</i>. The disparity between magnitude and potentially even sign of the calcification change under simulated end-of-century ocean surface chemical changes (higher <i>p</i>CO<sub>2</sub>, lower pH and carbonate saturation), raises challenges to quantifying future carbon cycle impacts and feedbacks because it introduces significant uncertainty in parameterizations used for global models. Here we compile the results of coccolithophore carbonate chemistry manipulation experiments and review how ocean carbon cycle models have attempted to bridge the gap from experiments to global impacts. Although we can rule out methodological differences in how carbonate chemistry is altered as introducing an experimental bias, the absence of a consistent calcification response implies that model parameterizations based on small and differing subsets of experimental observations will lead to varying estimates for the global carbon cycle impacts of ocean acidification. We highlight two pertinent observations that might help: (1) the degree of coccolith calcification varies substantially, both between species and within species across different genotypes, and (2) the calcification response across mesocosm and shipboard incubations has so-far been found to be relatively consistent. By analogy to descriptions of plankton growth rate vs. temperature, such as the "Eppley curve", which seek to encapsulate the net community response via progressive assemblage change rather than the response of any single species, we posit that progressive future ocean acidification may drive a transition in dominance from more to less heavily calcified coccolithophores. Assemblage shift may be more important to integrated community calcification response than species-specific response, highlighting the importance of whole community manipulation experiments to models in the absence of a complete physiological understanding of the underlying calcification process. However, on a century time-scale, regardless of the parameterization adopted, the atmospheric <i>p</i>CO<sub>2</sub> impact of ocean acidification is minor compared to other global carbon cycle feedbacks
Influencia de la concentración de la salmuera en la difusión de azúcares y cloruro de sodio durante el procesamiento de aceitunas verdes variedad Arauco
The green olive variety Arauco were debittered using lye concentrations of, 2.50% NaOH.They were then subjected to two rinsing processes with tap water. Next, the olives were cured with brines at 7%, 10% and 13% sodium chloride concentration. During this curing process, the loss of reducing sugars from the olives, and the diffusion of sodium chloride into the olives were quantified. Effective diffusion coefficients of both solutes in the skin and the flesh were calculated for this period using a diffusion model for a composite hollow sphere. The skin effective diffusion coefficients for both solutes ranged from entre 8,27x10-14- m2/s to 4,04x10-13 m2/s. The flesh coefficients varied from 2,92x10-9 m2/s to 3,99x10-9 m2/s for sodium chloride and from 9,76x10-11 m2/s to 2,22x10-10 m2/s for reducing sugars.Aceitunas verdes variedad Arauco fueron tratadas con soluciones de hidróxido de sodio al 2,5%. Estas fueron luego sometidas a dos procesos de lavado con agua corriente. Posteriormente, las aceitunas fueron curadas en salmueras con concentraciones de 7%, 10% y 13% de cloruro de sodio. Durante este proceso de curado, se cuantificó la pérdida de azúcares reductores desde, y la difusión de cloruro de sodio hacia el interior de las aceitunas. Durante este período se calcularon los coeficientes efectivos de difusión de ambos solutos en la piel y la pulpa, utilizando un modelo de difusión en una esfera hueca compuesta. Los coeficientes efectivos de difusión de ambos solutos en la piel estuvieron en un rango entre 8,27x10-14- m2/s y 4,04x10-13 m2/s. Los coeficientes de la pulpa variaron entre 2,92x10-9 m2/s y 3,99x10-9 m2/s para el cloruro de sodio, y entre 9,76x10-11 m2/s y 2,22x10-10 m2/s para los azúcares reductores
Quantifying Collaboration Quality in Face-to-Face Classroom Settings Using MMLA
Producción CientíficaThe estimation of collaboration quality using manual observation and coding is a tedious and difficult task. Researchers have proposed the automation of this process by estimation into few categories (e.g., high vs. low collaboration). However, such categorical estimation lacks in depth and actionability, which can be critical for practitioners. We present a case study that evaluates the feasibility of quantifying collaboration quality and its multiple sub-dimensions (e.g., collaboration flow) in an authentic classroom setting. We collected multimodal data (audio and logs) from two groups collaborating face-to-face and in a collaborative writing task. The paper describes our exploration of different machine learning models and compares their performance with that of human coders, in the task of estimating collaboration quality along a continuum. Our results show that it is feasible to quantitatively estimate collaboration quality and its sub-dimensions, even from simple features of audio and log data, using machine learning. These findings open possibilities for in-depth automated quantification of collaboration quality, and the use of more advanced features and algorithms to get their performance closer to that of human coders.European Union via the European Regional Development Fund and in the context of CEITER and Next-Lab (Horizon 2020 Research and Innovation Programme, grant agreements no. 669074 and 731685)Junta de Castilla y León (Project VA257P18)Ministerio de Ciencia, Innovación y Universidades (Project TIN2017-85179-C3-2-R
- …