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Staying at the front line in learning research is challenging because many fields are rapidly developing. One such field is research on the temporal aspects of computer-supported collaborative learning (CSCL). To obtain an overview of these fields, systematic literature reviews can capture patterns of existing research. However, conducting systematic literature reviews is time-consuming and do not reveal future developments in the field. This study proposes a machine learning method based on topic modelling that takes articles from a systematic literature review on the temporal aspects of CSCL (49 original articles published before 2019) as a starting point to describe the most recent development in this field (52 new articles published between 2019 and 2020). We aimed to explore how to identify new relevant articles in this field and relate the original articles to the new articles. First, we trained the topic model with the Results, Discussion, and Conclusion sections of the original articles, enabling us to correctly identify 74% (n = 17) of new and relevant articles. Second, clusterisation of the original and new articles indicated that the field has advanced in its new and relevant articles because the topics concerning the regulation of learning and collaborative knowledge construction related 26 original articles to 10 new articles. New irrelevant studies typically emerged in clusters that did not include any specific topic with a high topic occurrence. Our method may provide researchers with resources to follow the patterns in their fields instead of conducting repetitive systematic literature reviews.

(E)-6-Methoxy-1-methyl-3-(2-(3-methyl-4-nitroisoxazol-5-yl)vinyl)quinolin-2(1H)-one dye (MQI) has been synthesized, and its structural and electronic properties have been characterized by employing UV-vis spectroscopy in combination with computational methods. The MQI dye has been assessed as an activated Michael acceptor-type probe toward bisulfite ions. This reaction was kinetically tested in different mild, cationic (cetyltrimethylammonium bromide, cetyltrimethylammonium chloride, and cetylpyridinium bromide), and zwitterionic (N-decyl-N,N-dimethyl-3-ammonio-1-propanesulfonate, N-tetradecyl-N,N-dimethyl-3-ammonio-1-propanesulfonate, and N-hexacyl-N,N-dimethyl-3-ammonio-1-propanesulfonate) micellar solutions at pH ∼ 5.5. Both micellar media remarkably allow the addition reactions, increasing the reactivity of MQI towards bisulfite ions, the biggest effects were found in the presence of cationic micelles. The binding constants of MQI with the micelles and the rate constants were determined from kinetic data, which were interpreted on the basis of the pseudophase kinetic model. The kinetic study and the product analysis allow us to highlight the relevant role of the association between MQI dye and the micellized surfactant, allowing efficient nucleophilic addition of bisulfite ions. The findings of this work will be valuable for the use of micellar solutions as an alternative medium to replace the use of toxic solvents to carry out organic reactions to perform nucleophilic addition reactions of bisulfite. [ABSTRACT FROM AUTHOR]

Abstract: The ultimate goal of future neutrino facilities is the determination of CP violation in neutrino oscillations. Besides , this will require precision experiments with a very intense neutrino source and energy control. With this objective in mind, the creation of monochromatic neutrino beams from the electron capture decay of boosted ions by the SPS of CERN has been proposed. We discuss the capabilities of such a facility as a function of the energy of the boost and the baseline for the detector. We compare the physics potential for two different configurations: (I) and (maximum achievable at present SPS) to Frejus; (II) and (maximum achievable at upgraded SPS) to Canfranc. We conclude that the SPS upgrade to 1000 GeV is important to reach a better sensitivity to CP violation iff it is accompanied by a longer baseline. [Copyright &y& Elsevier]

Poly[(5,5'-(2,3-bis(2-ethylhexyloxy)naphthalene-1,4-diyl)bis(thiophene-2,2′-diyl))-alt-(2,1,3-benzothiadiazole-4,7-diyl)] (PEHONDTBT) was synthesized for the first time and through direct arylation polymerization (DAP) for use as p-donor material in organic solar cells. Optimized reaction protocol leads to a donor-acceptor conjugated polymer in good yield, with less structural defects than its analog obtained from Suzuki polycondensation, and with similar or even higher molecular weight than other previously reported polymers based on the 2,3-dialkoxynaphthalene monomer. The batch-to-batch repeatability of the optimized DAP conditions for the synthesis of PEHONDTBT was proved, showing the robustness of the synthetic strategy. The structure of PEHONDTBT was corroborated by NMR, exhibiting good solubility in common organic solvents, good film-forming ability, and thermal stability. PEHONDTBT film presented an absorption band centered at 498 nm, a band gap of 2.15 eV, and HOMO and LUMO energy levels of −5.31 eV and −3.17 eV, respectively. Theoretical calculations were performed to understand the regioselectivity in the synthesis of PEHONDTBT and to rationalize its optoelectronic properties. Bilayer heterojunction organic photovoltaic devices with PEHONDTBT as the donor layer were fabricated to test their photovoltaic performance, affording low power-conversion efficiency in the preliminary studies. [ABSTRACT FROM AUTHOR]

The next generation of long baseline neutrino experiments will aim at determining the value of the unknown mixing angle, θ13, the type of neutrino mass hierarchy and the presence of CP-violation in the lepton sector. Beta-beams and electron capture experiments have been studied as viable candidates for long baseline experiments. They use a very clean electron neutrino beam from the β-decays or electron capture decays of boosted ions. In the present article we consider an hybrid setup which combines a beta-beam with an electron capture beam by using boosted Ytterbium ions. We study the sensitivity to the CP-violating phase δ and the θ13 angle, the CP-discovery potential and the reach to determine the type of neutrino mass hierarchy for this type of long baseline experiment. The analysis is performed for different neutrino beam energies and baselines. Finally, we also discuss how the results would change if a better knowledge of some of the assumed parameters was achieved by the time this experiment could take place. [ABSTRACT FROM AUTHOR]

In the last few years spectacular results have been achieved with the demonstration of non vanishing neutrino masses and flavour mixing. The ultimate goal is the understanding of the origin of these properties from new physics. In this road, the last unknown mixing [Ue3] must be determined. If it is proved to be non-zero, the possibility is open for Charge Conjugation-Parity (CP) violation in the lepton sector. This will require precision experiments with a very intense neutrino source. Here a novel method to create a monochromatic neutrino beam, an old dream for neutrino physics, is proposed based on the recent discovery of nuclei that decay fast through electron capture. Such nuclei will generate a monochromatic directional neutrino beam when decaying at high energy in a storage ring with long straight sections. We also show that the capacity of such a facility to discover new physics is impressive, so that fine tuning of the boosted neutrino energy allows precision measurements of the oscillation parameters even for a [Ue3] mixing as small as 1 degree. We can thus open a window to the discovery of CP violation in neutrino oscillations. [ABSTRACT FROM AUTHOR]