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During many past decades, scientists from various countries have studied separately the atmospheric motions in the lower atmosphere, in the Earth's magnetic field, in the magnetospheric currents, etc. All of these separate studies lead today to the global study of the Sun and Earth connections, and as a consequence, new scientific programs (IHY- International Heliophysical Year, CAWSES- Climate and Weather in the Sun-Earth System) are defined, in order to assume this new challenge. In the past, many scientists did not have the possibility to collect data at the same time in the various latitude and longitude sectors. Now, with the progress of geophysical sciences in many developing countries, it is possible to have access to worldwide data sets. This paper presents the particularities of geophysical parameters measured by the Vietnamese instrument networks. It introduces a cooperative Vietnamese-IGRGEA (International Geophysical Research Group Europe Africa) project, and presents, for the first time, to the international community, the geophysical context of Vietnam. Concerning the ionosphere: since 1963, during four solar cycles, the ionosonde at Phu Thuy (North Vietnam) was operating. The Phu Thuy data exhibits the common features for the ionospheric parameters, previously observed in other longitude and latitude sectors. The critical frequencies of the E, F1 and F2 ionospheric layers follow the variation of the sunspot cycle. F2 and E critical frequencies also exhibit an annual variation. The first maps of TEC made with data from GPS receivers recently installed in Vietnam illustrate the regional equatorial pattern, i.e. two maxima of electronic density at 15° N and 15° S from the magnetic equator and a trough of density at the magnetic equator. These features illustrate the equatorial fountain effect. Concerning the Earth's magnetic field: a strong amplitude of the equatorial electrojet was first observed by the CHAMP satellite at the height of 400 km in the Vietnamese longitude sector. In this paper we compare the ground magnetic observations of the Indian and Vietnamese magnetometer networks. This comparison highlights the regional structure of the amplitude of the equatorial electrojet, which is stronger in Vietnam than in India. Concerning the monsoon: Vietnam exhibits a strong monsoon and has mainly one rainy season peaking in August, hence associated with the southwest monsoon flow. But some monsoon variability from one place to another is related to the orography. In the mountainous northern regions of Vietnam, there is an "early" monsoon peaking in July. In the coastal regions between 12° N and 19° N the monsoon season is centered on October. Concerning lightning: Vietnam is a country of strong atmospheric storms with some areas of very intense lightning in North Vietnam (22,5° N, 105° E) and in South Vietnam (11° N, 107° E). In North Vietnam strong lightning is associated with the most intense rainy region.

A novel anticoincidence detector is proposed for the measurement of 478 keV gamma radiation for evaluation of boron neutron capture therapy. The Compton continuum around the target photopeak position is effectively suppressed by measuring only the Compton gamma rays scattered at small angles from the primary detector. A numerical evaluation using Monte Carlo simulations estimated an 80% reduction in counts, and the developed prototype detector showed 4% suppression of the Compton continuum of cobalt-60 gamma rays., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Across the world and within Europe, a growing number of consumers are choosing to buy gluten-free products. Motivations for a gluten-free diet and the consequences of consuming gluten are varied, from a medical necessity for those diagnosed with celiac disease to a range of health complications and discomfort for those who are gluten-intolerant. In this research, 7296 gluten-free consumers across 13 European countries responded to an online survey on the 33 types of gluten-free products purchased, how frequently they purchased them, their satisfaction with gluten-free quality and availability, the problems they have experienced, and the strategies they have employed to cope with these problems. The investigation examines whether and how these consumer attitudes and behaviors differ between those diagnosed with celiac disease, those who are gluten-intolerant, and those who are caregivers for others with a gluten-free diet. The results show that significant differences existed for all these habits and issues across the three gluten-free consumer groups. Specifically, caregivers purchased most of the gluten-free product types more frequently than the other two groups, experienced more availability problems, and were more likely to shop at multiple stores or make their own gluten-free products. Celiac-diagnosed consumers tended to buy gluten-free products more frequently than those who are gluten-intolerant, and they tended to be the most satisfied with the quality and range of gluten-free offerings. Despite purchasing frequency differences between the groups, the results suggest a similar hierarchy of gluten-free products that could provide the foundation for a European gluten-free food basket.

A compact gamma-ray sensor composed of a cadmium sulfide (CdS) photoresistor and a small-sized cesium iodine doped thallium scintillator is introduced for intense gamma-ray monitoring. The sensor exhibits radiation-resistant ability and a linear output response over a wide dose range. The dose rate at several conditions was measured for confirmation of feasibility. Experimental results demonstrated its advantage for gamma-ray measurements in intense fields as an inexpensive, robust, compact, and high-sensitivity device., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

In this paper, we ask whether the structure of investor networks, estimated using shareholder registration data, is abnormal during a financial crises. We answer this question by analyzing the structure of investor networks through several most prominent global network features. The networks are estimated from data on marketplace transactions of all publicly traded securities executed in the Helsinki Stock Exchange by Finnish stock shareholders between 1995 and 2016. We observe that most of the feature distributions were abnormal during the 2008-2009 financial crisis, with statistical significance. This paper provides evidence that the financial crisis was associated with a structural change in investors' trade time synchronization. This indicates that the way how investors use their private information channels changes depending on the market conditions.