42 research outputs found
Morphometric Analysis of the 18th Century Vitis sp. Seeds from Apulum Archaeological Site
The present study examines Vitis sp. seeds discovered during the excavations in 2017 on an archaeological site in Apulum, the current city of Alba Iulia, Romania. The archaeological context was dated as belonging to the 18th century. The grape seeds were measured in order to determine whether they are cultivated or wild. Using mathematical formulas and keys given for interpretation, all the seeds were determined as being cultivated. The results obtained complete the archaeological information regarding Vitis sp. use in human diet during Modern era in Transylvania
Greek Economy: Back to the Past
The Greek economy has been characterized by successive phases of growth and recession with marked changes in its macroeconomic data over the last twenty years, which have affected the social reality of the country. The growth phase resulted in the deadlocks of 2009 (deficits, debt and EU rules) and the recession phase, which was determined by the memorandum programs through internal devaluation, resulted in a drastic reduction in national income (28%). During the last two years, the country has been led back to a downward path (recession – pandemic) with unspecified final consequences for the economy and society. In typical terms, the performance of the Greek economy refers to the past (90s), and in this case there are strong doubts about its strategy and objectives.
Keywords: EU, Greece, crisi
Two decades of homogenized satellite ozone measurements for climate services
Since the launch of GOME onboard ERS-2 in 1995 total and tropospheric ozone have been derived from European satellite instruments. In the framework of the ESA CCI and the EU ECMWF C3S projects, BIRA generates total ozone products from the satellite sensors GOME, SCIAMACHY, OMI, and GOME-2 using the GODFIT algorithm and DLR is responsible for harmonizing the total column data from all these sensors and generating a merged product, which encompasses more than two decades of global total ozone observations.
Additionally, tropospheric ozone columns form the European sensors are generated by DLR using the convective cloud differential algorithm. Total and tropospheric ozone from GOME-2 onboard MetOp-A and -B are operational products from the EUMETSAT AC-SAF and within the ESA CCI project the tropical tropospheric ozone products from GOME, SCIAMACHY, OMI, and GOME-2 were harmonized and a merged data product was delivered and has been updated regularly.
On a global scale a slight increase in total ozone columns is observed over the years since 1995 until today indicating that the total ozone starts to emerge into the expected recovery phase. Tropospheric data from the last 22 years show a slightly increasing trend with strong regional variations especially in the tropical eastern Pacific and Atlantic Ocean.
These unique ozone datasets will be extended during the next two decades with measurements from the EU Copernicus missions Sentinel-5 Precursors (successfully launched in October 2017) and the future Sentinel-4 and Sentinel-5 missions
Зіставлення наземних та супутникових вимірювань загального вмісту озону над антарктичними станціями
Проведено порівняння наземних та супутникових вимірювань загального вмісту озону (ЗВО) в атмосфері над антарктичними станціями Академік Вернадський, Ротера, Галлі та Амундсен-Скотт. Такий аналіз розбіжності даних здійснюється за допомогою глобальної мережі наземних озонометричних станцій з початку регулярних супутникових спостережень (1978 р.). В останнє десятиріччя зафіксовано уповільнення багаторічних глобальних втрат озону і прогнозується відновлення озонового шару в наступні десятиріччя. Тому підвищуються вимоги до точності реєстрації змін ЗВО, що у свою чергу потребує відповідного аналізу похибок вимірювань. У роботі використано дані супутникового спектрометра EP-TOMS за 1996–2005 роки. Щоденні супутникові значення ЗВО взято за останньою, восьмою версією алгоритму, введеною 2004 року та емпірично скоригованою 2007-го. Проаналізовано вплив сезонних змін ЗВО над антарктичним реґіоном на розбіжність між наземними та супутниковими вимірюваннями. Найбільш стійкими особливостями є: 1) значне зростання дисперсії відносної різниці «супутник–станція» в період весняного зниження ЗВО і формування озонової діри та 2) залежність різниці від рівня ЗВО.Проведено сравнение наземных и спутниковых измерений общего содержания озона (ОСО) в атмосфере над антарктическими станциями Академик Вернадский, Ротера, Халли и Амундсен-Скотт. Такой анализ расхождения данных осуществляется при помощи глобальной сети наземных озонометрических станций с начала регулярных спутниковых наблюдений (1978 г.). В последнее десятилетие фиксируется замедление многолетних глобальных потерь озона и прогнозируется возобновление озонового слоя в последующие десятилетия. Поэтому повышаются требования к точности регистрации изменений ОСО, что в свою очередь требует соответствующего анализа погрешностей измерений. В работе использованы данные спутникового спектрометра EP-TOMS за 1996–2005 гг. Ежедневные спутниковые значения ОСО взяты по последней, восьмой версии алгоритма, введенной в 2004 г. и эмпирически скорректированной в 2007 г. Проанализировано влияние сезонных изменений ОСО над антарктическим регионом на расхождение наземных и спутниковых измерений. Наиболее стойкими особенностями являются: 1) значительное возрастание дисперсии относительной разности «спутник–станция» в период весеннего снижения ОСО и формирования озоновой дыры и 2) зависимость разности от уровня ОСО.Comparison of the ground-based and satellite total ozone content (TOC) measurements in the atmosphere over the Antarctic stations Akademik Vernadsky, Rothera, Halley and Amundsen-Scott has been carried out. Similar discrepancy analysis is made using global network of the ground-based ozonometric stations from the beginning of the regular satellite observations (1978). Slowing of the long-term global ozone losses has observed during last decade and recovering of the ozone layer is forecasted for the next decades. Therefore, the accuracy requirements to the ozone change registration are increased, that, in turn, requires corresponding analysis of the measurement errors. In this work, the EP-TOMS satellite data of 1996-2005 are used. Satellite daily TOC values are taken by the last 8th Version of the algorithm introduced in 2004 and empirically corrected in 2007. Influence of the seasonal TOC changes over Antarctic region on the difference between ground-based and satellite measurements is analyzed. The most persistent features are: 1) significant increase of the dispersion of the relative “satellite – station” difference in the period of the spring TOC decrease and ozone hole formation and 2) difference dependence on the TOC level
Communications cellulaires (1975-2006)
Publications Koukouli F., Rooy M., Changeux J.-P. et Maskos U., « Nicotinic receptors in mouse prefrontal cortex modulate ultraslow fluctuations related to conscious processing », Proceedings of the National Academy of Sciences of the United States of America, vol. 113, no 51, 2016, p. 14823-14828, DOI : 10.1073/pnas.1614417113. Evers K. et Changeux J.-P., « Proactive epigenesis and ethical innovation: A neuronal hypothesis for the genesis of ethical rules », EMBO reports, vol. 17, no 10, 201..
TROPOMI/S5P Total Column Water Vapor validation against AERONET ground-based measurements
First water vapor measurement over Athens, Greece, obtained by a combined Raman-elastic backscatter lidar system
GOME-2 total ozone columns from MetOp-A/MetOp-B and assimilation in the MACC system
The two Global Ozone Monitoring Instrument (GOME-2) sensors operated in
tandem are flying onboard EUMETSAT's (European Organisation for the Exploitation of Meteorological Satellites) MetOp-A and MetOp-B satellites,
launched in October 2006 and September 2012 respectively. This paper
presents the operational GOME-2/MetOp-A (GOME-2A) and
GOME-2/MetOp-B (GOME-2B)
total ozone products provided by the EUMETSAT Satellite
Application Facility on Ozone and Atmospheric Chemistry Monitoring (O3M-SAF).
These products are generated using the latest version of the GOME
Data Processor (GDP version 4.7). The enhancements in GDP 4.7, including the
application of Brion–Daumont–Malicet ozone absorption cross sections, are
presented here. On a global scale, GOME-2B has the same high accuracy as the
corresponding GOME-2A products. There is an excellent agreement between the
ozone total columns from the two sensors, with GOME-2B values slightly lower
with a mean difference of only 0.55±0.29%. First global validation
results for 6 months of GOME-2B total ozone using ground-based measurements
show that on average the GOME-2B total ozone data obtained with GDP 4.7 are
slightly higher than, both, Dobson observations by about 2.0±1.0% and
Brewer observations by about 1.0±0.8%. It is concluded that the
total ozone columns (TOCs) provided by GOME-2A and GOME-2B are consistent
and may be used simultaneously without introducing systematic effects, which
has been illustrated for the Antarctic ozone hole on 18 October 2013.
GOME-2A total ozone data have been used operationally in the Copernicus
atmospheric service project MACC-II (Monitoring Atmospheric Composition and
Climate – Interim Implementation) near-real-time (NRT) system since October 2013.
The magnitude of the bias correction needed for assimilating GOME-2A
ozone is reduced (to about −6 DU in the global mean) when the GOME-2 ozone
retrieval algorithm changed to GDP 4.7
Altimetry of the Venus cloud tops from the Venus Express observations
Simultaneous observations of Venus by Visible and Infrared Thermal Imaging Spectrometer and Venus Monitoring Camera onboard the Venus Express spacecraft are used to map the cloud top altitude and to relate it to the ultraviolet (UV) markings. The cloud top altitude is retrieved from the depth of CO2 absorption band at 1.6 μm. In low and middle latitudes the cloud top is located at 74 ± 1 km. It decreases poleward of ±50° and reaches 63–69 km in the polar regions. This depression coincides with the eye of the planetary vortex. At the same latitude and hour angle, cloud top can experience fast variations of about 1 km in tens of hours, while larger long-term variations of several kilometers have been observed only at high latitudes. UV markings correlate with the cloud altimetry, however, the difference between adjacent UV dark and bright regions does not exceed several hundred meters. Surprisingly, CO2 absorption bands are often weaker in the dark UV features, indicating that these clouds may be a few hundred meters higher or have a larger scale height than neighboring clouds. Ultraviolet dark spiral arms, which are often seen at about −70°, correspond to higher altitudes or to the regions with strong latitudinal gradient of the cloud top altitude. Cloud altimetry in the polar region reveals the structure that correlates with the thermal emission maps but is invisible in UV images. This implies that the UV optically thick polar hood is transparent in the near IR