Search for neutrino decay during the 1999 solar eclipse

The solar neutrino problem could arise from oscillation of one neutrinotype into a secondtype. Neutrinos would have a mass and there could be the possibility ofradiative neutrino decays. We discuss the search for neutrino decaysduring the 1999 solar eclipse: it involves the emitted visible photons,while neutrinos travel from the Moon to the Earth. The concept and themain characteristics of the NOTTE experiment are presented.     

Provenance of Oligocene lithic and quartz arenites of the East Carpathians: Understanding sediment routing systems on compressional basin margins

We present new sedimentological, petrographical, palaeontological and detrital zircon U–Pb data on late Oligocene–early Miocene sedimentary rocks of the thin-skinned thrust belt of East Carpathians. These data were acquired to reconstruct the sedimentary routing system for two compositionally different turbidite fans made of the regionally extensive Kliwa and Fusaru formations. On the eastern margin of the Moldavides foreland basin, large low-gradient river systems draining the East European Platform provided well-sorted quartz-rich sand forming deltas on wide shallow shelves and thick Kliwa submarine fans. Due to the westward subduction of a thinned continental plate, the western basin margin was characterized by short, steep-gradient routing systems where sediment transport to deep water was mainly through hyperpycnal flows. The Getic and Bucovinian nappes of the East Carpathians and the exhumed Cretaceous–Early Palaeogene orogenic wedge fed Fusaru fans with poorly sorted lithic sand. The Fusaru fans trend northwards in the foredeep basin having an elongate depocentre, interfingering and then overlapping on the distal part of the Kliwa depositional system due to the eastward advance of the Carpathian fold-and-thrust belt. A smaller sediment input is supplied by southern continental areas (i.e. Moesian Platform, North Dobrogea and potentially the Balkans). In general, the sandstone interfingering between distinct basin floor fan systems is less well documented because the facies would be similar and there are not many systems that have a distinct sediment provenance like Kliwa and Fusaru systems. This case study improves the understanding of regional palaeogeography and sedimentary routing systems and provides observations relevant here or elsewhere on the interfingering turbidite fan systems.     

A Multi-Angle Averaging Theorem Applied to the J2 Problem

A particular multi-angle averaging theorem for systems admitting a finite Fourier expansion of the field is presented, together with its application to the problem of motion around an oblate planet (the J₂ problem), in harmonic oscillator formulation. This method of approximate integration has the advantage of working with (close on) directly measurable elements. This revised version was published online in July 2006 with corrections to the Cover Date.     

Influence of 1 GHz radiation at low specific absorption rate of energy deposition on plant mitotic division process

The biological impact of microwaves exposure on biosphere is presently an important research subject. With the significant increase of communications technology use, of industrial and military activities which involve radiofrequency radiation, electromagnetic pollution became very intense in the last years. The aim of the present work was to investigate the genotoxic influence of microwaves on Zea mays seeds. They were exposed in controlled conditions for different durations at 1 GHz continuous wave providing a low specific absorption rate of energy. Post-exposure the mitotic- and chromosomal aberrations indexes were determined. Qualitatively, a wide range of abnormal mitotic stages were detected in cells of exposed seeds in comparison with the control. Quantitatively, slight stimulatory effect on mitotic division process, expressed by an enhanced percentage of dividing cells (increased of 26% for 180 min exposure), for all exposed samples was revealed, while lowered level of induced chromosomal aberrant cells percentage (up to 2.14%) was also found. The aberrations percentage and mitotic index increased in time-dependent manner on exposure dose.     

Investigation of the variability of strong ground motions from Vrancea earthquakes

A systematic investigation of the applicability of several ground motion prediction models for Vrancea intermediate-depth seismic source is conducted in this research. Two ground motion prediction models recommended by previous evaluations (Vacareanu et al. in Bull Earthq Eng 11(6):1867–1884, 2013a; Pavel et al. in Earthq Struct 6(1):1–18, 2014), as well as two new state-of-the-art ground motion prediction equations (Vacareanu et al. in J Earthq Eng, 2013b; Earthq Struct 6(2):141–161, 2014) are tested using an increased strong ground motion database consisting of 150 recordings from Vrancea subcrustal earthquakes. The evaluation is performed by using several goodness-of-fit parameters from the literature. Moreover, the applicability of the single-station sigma method is also investigated by using the same strong ground motion database recorded in 30 seismic stations from southern and eastern Romania. The influence of the soil conditions on the numerical results obtained in this study is investigated and discussed using the results provided by the analysis of variance method. The impact of the single-station standard deviation on the levels of seismic hazard is also assessed in this study, and the results show, in the analyzed cases, significant reductions of the hazard levels.     

Climate change perception in Romania

Theoretical and Applied Climatology - In the last decades, anthropogenic drivers have significantly influenced the natural climate variability of Earth’s atmosphere. Climate change has become...     

A deep-seated landslide dam in the Siriu Reservoir (Curvature Carpathians, Romania)

The Groapa Vântului (Wind’s Dip) landslide, situated in the Buz?u Carpathians, on the right-hand slope of the Siriu Reservoir, occurred in April 2006, after the first local movements were signaled in September–October 2005. It represents a reactivation of an older, apparently relict (and well covered by a secular beech forest) landslide, which blocked Siriu Reservoir for several weeks and caused a major change in the sedimentation regime downstream of it. The volume of the displaced material reached almost 2.5 million m³, affecting a surface of more than 250,000 m² and reducing the reservoir’s volume by almost 2 million m³. The landslide developed on a lithological contact of Paleogene flysch formations and features steep (40–50°) and high (up to 30 m) scarps, as well as complex inner sectors, of rotational, translational, and compresional movement. The assessment of landslide’s morphodynamic behavior is based on repeated geomorphological field mapping and measurements, differential Global Positioning System, and total station profiles, and mobile and fixed landmarks. This preliminary assessment contributes to the understanding of the behavior of old, peri-glacial landslide reactivations and also represents progress towards a better hazard assessment.     

Bianchi type-I string cosmological model in the presence of a magnetic field: classical versus loop quantum cosmology approaches

A Bianchi type-I cosmological model in the presence of a magnetic flux along a cosmological string is considered. The first objective of this study is to investigate Einstein equations using a tractable assumption usually accepted in the literature. Quantum effects of the present cosmological model are examined in the framework of loop quantum cosmology. Finally we draw a parallel between the classical and quantum approaches.     

Biperiodic orbital period modulation of the W UMa binary system CK Bootis

A study of the orbital period variation of the W UMa system CK Bootis is made using an extended observational time base. The biperiodicity of the orbital period modulation is emphasized. Both detected periodicities (24.14 yr and 10.62 yr) cannot be explained through the light-time effect unless the companion would be a white dwarf as suggested by other authors, too. Moreover, we also argue that, nowadays at least, it seems that there is no causal relation between the orbital period variation and the recently discovered visual companion. Consequently, we infer that at least one of the two periodicities may be related to the magnetic activity cycles in the component stars of CK Boo, while the other periodicity could be related to the presence of a fourth companion in the system.