Exploring atmospheric radon with airborne gamma-ray spectroscopy

$^{222}$Rn is a noble radioactive gas produced along the $^{238}$U decay chain, which is present in the majority of soils and rocks. As $^{222}$Rn is the most relevant source of natural background radiation, understanding its distribution in the environment is of great concern for investigating the health impacts of low-level radioactivity and for supporting regulation of human exposure to ionizing radiation in modern society. At the same time, $^{222}$Rn is a widespread atmospheric tracer whose spatial distribution is generally used as a proxy for climate and pollution studies. Airborne gamma-ray spectroscopy (AGRS) always treated $^{222}$Rn as a source of background since it affects the indirect estimate of equivalent $^{238}$U concentration. In this work the AGRS method is used for the first time for quantifying the presence of $^{222}$Rn in the atmosphere and assessing its vertical profile. High statistics radiometric data acquired during an offshore survey are fitted as a superposition of a constant component due to the experimental setup background radioactivity plus a height dependent contribution due to cosmic radiation and atmospheric $^{222}$Rn. The refined statistical analysis provides not only a conclusive evidence of AGRS $^{222}$Rn detection but also a (0.96 $\pm$ 0.07) Bq/m$^{3}$ $^{222}$Rn concentration and a (1318 $\pm$ 22) m atmospheric layer depth fully compatible with literature data.Comment: 17 pages, 8 figures, 2 table

Thermal signal propagation in soils in Romania: conductive and non-conductive processes

Temperature data recorded in 2002 and 2003 at 10 stations out of the 70 available in the Romanian automatic weather stations network are presented and analyzed in terms of the heat transfer from air to underground. The air temperature at 2 m, the soil temperatures at 0, 5, 10, 20, 50 and 100 cm below the surface as well as rain fall and snow cover thickness have been monitored. The selected locations sample various climate environments in Romania. Preliminary analytical modelling shows that soil temperatures track air temperature variations at certain locations and, consequently, the heat transfer is by conduction, while at other stations processes such as soil freezing and/or solar radiation heating play an important part in the heat flux balance at the air/soil interface. However, the propagation of the annual thermal signal in the uppermost one meter of soil is mainly by conduction; the inferred thermal diffusivity for 8 stations with continuous time series at all depth levels ranges from 3 to 10×10<sup>−7</sup> m<sup>2</sup> s<sup>−1</sup>

From Theory to Action: Developing and Evaluating Learning Analyticsfor Learning Design

Producción CientíficaThe effectiveness of using learning analytics for learning design primarily depends upon two concepts: grounding and alignment. This is the primary conjecture for the study described in this paper. In our design-based research study, we design, test, and evaluate teacher-facing learning analytics for an online inquiry science unit on global climate change. We design our learning analytics in accordance with a socioconstructivism-based pedagogical framework, called Knowledge Integration, and the principles of learning analytics Implementation Design. Our methodology for the design process draws upon the principle of the Orchestrating for Learning Analytics framework to engage stakeholders (i.e. teachers, researchers, and developers). The resulting learning analytics were aligned to unit activities that engaged students in key aspects of the knowledge integration process. They provided teachers with actionable insight into their students' understanding at critical junctures in the learning process. We demonstrate the efficacy of the learning analytics in supporting the optimization of the unit's learning design. We conclude by synthesizing the principles that guided our design process into a framework for developing and evaluating learning analytics for learning design.Ministerio de Ciencia, Innovación y Universidades (Project TIN2017-85179-C3-2-R)Junta de Castilla y León (project VA257P18) by the European Commission under project grant 588438-EPP-1-2017-1-EL-EPPKA2-KA

Surgery in postoperator alkaline desease

Clinica de Chirurgie Generală şi Esofagiană, Spitalul Clinic “Sfânta Maria” Bucureşti, România, Al XI-lea Congres al Asociației Chirurgilor „Nicolae Anestiadi” din Republica Moldova și cea de-a XXXIII-a Reuniune a Chirurgilor din Moldova „Iacomi-Răzeșu” 27-30 septembrie 2011Introducere: Se analizează retrospectiv experienţa clinicii pe 30 de ani (1981-2010) privind diversia duodenală totală Y-Roux (DDT) în tratamentul bolii alcaline de reflux postoperator(BARP). Materiale şi metodă, rezultate: Din 89 de pacienţi cu gastrojejunostomie Y-Roux după rezecţie gastrică distală cu diverse indicaţii, am selecţionat 29 de pacienţi la care procedeul s-a folosit în tratamentul BARP. Am exclus 9 cazuri cu DDT pentru patologie primară de reflux alcalin. În 20 cazuri DDT a fost practicată ca o modalitate reconstructivă pe “stomac operat”: degastrogastrectomie sau conversie a montajului anastomotic preexistent (la bolnavi cu 1-3 operaţii în antecedente, cu tulburări severe de motilitate). Se constată o scădere a numărului de cazuri în ultimii ani. La 9 pacienţi DDT a fost utilizată ca intenţie curativă antireflux după chirurgia biliară:colecistectomie ± coledocoduodenostomie, constatând creşterea numărului de cazuri în ultima perioadă. Criteriile de indicaţie chirurgicală: clinice, radiologice, endoscopice, histologice au selecţionat pentru intervenţie cazurile severe. Se prezintă particularităţile tehnice ca şi consecinţele morfofuncţionale ale DDT. Rezultatele imediate sunt foarte bune: morbiditate minimă (o reintervenţie precoce pentru ocluzie digestivă înaltă) şi mortalitate postoperatorie zero. Rezultatele la distanţă –evaluate clinic, radiologic, endoscopic şi histologic- arată o ameliorare postoperatorie certă, cu excepţia anumitor forme histologice. Concluzii: Incidenţa BARP după chirurgia gastrică a scăzut, prin scăderea drastică a indicaţiei operatorii pentru boala ulceroasă; în schimb creşte relativ incidenţa acestei entităţi după chirurgia biliară. DDT este o procedură eficientă dar de rezervă, indicată în cazuri bine selecţionate. Se constată o ameliorare postoperatorie certa clinică, endoscopică şi histologică, cu excepţia gastritei atrofice şi a metaplaziei intestinale, care se ameliorează în mică măsură.Introduction. We analyzed the experience of the Clinic on past 30 years (1981-2010) regarding total duodenal diversion (TDD) with Roux- en- Y gastrectomy for postoperator alkaline reflux disease (PARD). Materials and method, results: Among 89 patients presenting Y-Roux gastrojejunostomy after gastric distal resection for various indications, we selected 29 patients in which the procedure was used as treatment of PARD. We excluded 9 patients with TDD for primary alkaline reflux disease. In 20 cases TDD was used as a reconstructive procedure on “operated stomach” : degastrogastrectomy or conversion of the existing anastomotic assembly (at patients with history of 1-3 gastric operations, with severe motility disorders). It is ascertained a decrease in the number of such cases in recent years. At another 9 patients TDD was used as an antireflux cure after biliary surgery: colecistectomy ± choledocoduodenostomy, noting the increase number of such cases lately. The criteria for surgery indication: clinicals, radiologycals, endoscopicals, histologicals selected for intervention severe cases. There are presentated techniques particularities and morfofunctional consequences of TDD. Immediate results were very good: minimal morbidity ( one early reintervention for acute digestive occlusion) and no postoperator mortality. Long time results – clinical, radiological, endoscopic and histological evaluated- showed a certain postoperator improvement, excepting some definite histological forms. Conclusions: PARD incidence after gastric surgery has decreased through drastically decrease of surgical indication for patients with gastroduodenal ulcer; after biliar surgery. TDD is an efficient procedure but as a backup, being indicated only in cases very carefully selected. It is observed a definite clinical, endoscopic and histological postoperator improvement excepting atrophic gastritis which is less improved

Sometimes nature doesn't work: absence of attention restoration in older adults exposed to environmental scenes

Background/Study Context: An accumulating body of literature indicates that contact with natural settings can benefit health and wellbeing. Numerous studies support Attention Restoration Theory (ART), which suggests that even short exposure to nature, as opposed to urban environments, can promote attention restoration by stimulating soft fascination. However, it is unclear whether the restorative effects hold in aging. This study tested nature effect on cognitive restoration in older people.Methods: Utilizing the Sustained Attention to Response Task (SART), we explored changes in attentional performance in 75 healthy older individuals before and after exposure to either natural or urban scenes. We checked for age-related differences by comparing the older sample to a group of 21 young participants.Results: We found no effects of environmental exposure for either attentional accuracy, sensitivity to visual targets or reaction times. Our older participants had worse accuracy and slower reaction times than a younger control group who used the same paradigm.Conclusion: The results of our study conducted with older adults show no attention restoration effects in this population. Potential geographical/cultural moderators as wells as methodological considerations are discussed to provide insights for future studies on cognitive restoration in older age

Electromagnetic follow-up of gravitational wave transient signal candidates

Pioneering efforts aiming at the development of multi-messenger gravitational wave and electromagnetic astronomy have been made. An electromagnetic observation follow-up program of candidate gravitational wave events has been performed (Dec 17 2009 to Jan 8 2010 and Sep 4 to Oct 20 2010) during the recent runs of the LIGO and Virgo gravitational wave detectors. It involved ground-based and space electromagnetic facilities observing the sky at optical, X-ray and radio wavelengths. The joint gravitational wave and electromagnetic observation study requires the development of specific image analysis procedures able to discriminate the possible electromagnetic counterpart of gravitational wave triggers from contaminant/background events. The paper presents an overview of the electromagnetic follow-up program and the image analysis procedures.Comment: Proceedings of the 12th International Conference on "Topics in Astroparticle and Underground Physics" (TAUP 2011), Munich, September 2011 (to appear in IoP Journal of Physics: Conference Series

Analysis of donor-derived cell-free DNA with 3 year outcomes in heart transplant recipients

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Moving towards a multidimensional dynamic approach to nature and health: A bioavailability perspective

The benefits of exposure to nature for health and well-being have been demonstrated across multiple disciplines. Recent work has sought to establish one ‘dose’ or type of nature exposure that is universally beneficial, which has proven difficult. We use the principles of psychopharmacology to look beyond the use of dose as a concept for prescribing nature. Instead, we posit a multidimensional model of bioavailability of nature to shift the focus beyond universal effects, and instead consider the relationship between health and nature as dynamic, changeable and heavily contextual. We propose that the bioavailability of nature interactions is constructed through understanding route of administration, dose and concentration. By delineating the mechanisms of health benefit derived from the type of behavioural interaction (through being, doing and living), the route of administration of nature interactions may be highly variable not just between, but also within, individuals. We propose concentration as being a meeting between the subjective aspects of the individual and the subjective qualities of the nature at that specific time and place. We use a ‘green equation’, for mapping the processes and pathways that belie the interaction between the person and their environment. Here, the nature/health association as a dynamic interaction, and we operationalise this within a multidimensional construct of bioavailability. We provide an overview of this testable model and summarise with preliminary evidence as well as a research agenda for the future

New insights into the efficient charge transfer of ternary chalcogenides composites of TiO2

Abstract A two-step solvothermal synthesis was adopted to prepare AgXSe2-TiO2 (X = In, Bi) composites. DFT study of the pristine parent samples showed the formation of the hexagonal phase of AgBiSe2, and tetragonal phase of AgInSe2 and TiO2, which corroborated the experimentally synthesised structures. Both the AgBiSe2-TiO2 and AgInSe2-TiO2 composites displayed enhanced visible light absorption and reduced band gap in the UV-DRS patterns. The XPS results exhibited a shift in binding energy values and the TEM results showed the formation of spherical nanoparticles of both AgBiSe2 and AgInSe2. The PL signals displayed delayed recombination of the photogenerated excitons. The as synthesised materials were studied for their photocatalytic efficiency, by hydrogen generation, degradation of doxycycline, and antimicrobial disinfection (E. coli and S. aureus). The composite samples illustrated more than 95 % degradation results within 180 min and showed 5 log reductions of bacterial strains within 30 min of light irradiation. The hydrogen production outcomes were significantly improved as the AgBiSe2 and AgInSe2 based composites illustrated 180-fold and 250-fold enhanced output compared to their parent samples. The enhanced photocatalytic efficiency displayed is attributed to the delayed charge recombination of the photogenerated electron-hole pairs in the AgXSe2-TiO2 interface. Formation of a p-n nano heterojunction for AgBiSe2-TiO2 and type II heterojunction for AgInSe2-TiO2 composite are explained