182 research outputs found
Iranian Scientist Reflects on Trump’s Attempted Immigration Ban
No full textEos caught up with Solmaz Adeli, an Iranian researcher based in Germany who was almost barred from entering the United States for an important scientific meeting.</jats:p
Zeitliche Entwicklung fluviatiler und glazialer Prozesse in den südlichen Hochländern
No full textThe history of water on Mars, after more than four decades of remote sensing
investigation, has still some ambiguities. This work focuses on the major
geological aspects of presence of water on the Martian surface in a regional
scale, with the aim of reconstructing the evolution of aqueous activities in
the Terra Sirenum–Terra Cimmeria region from the late Noachian epoch to the
late Amazonian and current conditions. The research presented here is based on
geomorphological observation, geological mapping, spectroscopical
investigation, hydraulic analysis, and age determination by using imagery,
topographic, and spectroscopic data. The study area is thought to have played
host to one of the largest paleolakes on Mars, known as the Eridania lake
which is believed to have existed during middle-late Noachian. This work
provides new insights into the depositional, erosional, alteration mechanisms,
and development of liquid water existence from the early Mars large bodies of
water (e.g., Eridania lake), into local Amazonian fluvial and ice-related
features. The large Eridania lake drained into the Ma’adim Valles and
transformed into isolated closed lakes after the late Noachian-early Hesperian
boundary. The closed lakes may have lasted over a long geological time,
believed to be during the Hesperian period, which is evidenced mainly by the
thickness of the sediments and various alteration products. The presence of
materials rich in Fe/Mg-phyllosilicates, Al-phyllosilicates, and chloride
salts, in addition to their stratigraphical relation, suggests chemical
environment change(s) at the last stages of the lakes existence and/or after
their desiccation. The produced geologic map combined with the age
determination results show that the bodies of water, related alteration and
erosional processes, took place before the early Amazonian epoch. The presence
of a ~340 km long fluvial valley system located southwest of the Eridania lake
hypothesised shoreline, dated as early to middle Amazonian, indicates that the
liquid water presence on the surface of the Terra Sirenum–Terra Cimmeria
region has not completely ceased after the isolated lakes disappearance. At
the downstream section of the fluvial system a unique braided alluvial fan has
been observed in the Kārūn Valles, which has not been previously reported. The
morphological observations and hydraulic analysis point to geologically short-
term event(s) which may have taken a few days up to a few tens of thousands of
days to form the Kārūn Valles alluvial fan, and consequently the correspondent
upstream fluvial features. The source of water is assessed as surface run-off
due to ice/snow melt. This observation reveals that liquid water was present
on the Martian surface during early-middle Amazonian. Under the current
climatic conditions, which do not sustain the accumulation of ice/snow on the
surface, several ice-rich and glacial-related features have been observed on
the floor of the mentioned valley system. The morphology and stratigraphy of
these valley fill deposits (VFD) infer to a formation prior to the latitude
dependent mantle (LDM) emplacement. The VFD presence supports the previously
hypothesised Amazonian climate change phases, at mid-latitudes, due to
obliquity oscillations. These deposits, their host fluvial valley, and the
rich past aqueous history of Terra Sirenum-Terra Cimmeria, show that the water
re-appeared on the Martian surface repeatedly over time, although its
abundance decreased from the late Noachian to the current late Amazonian
epoch.Selbst nach vier Jahrzehnten der fernerkundlichen Erforschung, ist die
Entwicklung der Wasservorkommen auf dem Mars nicht vollständig verstanden.
Diese Arbeit legt ihr Augenmerk auf die wichtigsten geologischen Aspekte von
Wasservorkommen auf der Marsoberfläche in regionalem Maßstab. Das Ziel ist die
aquatische Entwicklung in den Regionen Terra Cimmeria und Terra Sirenum seit
der späten Noachischen bis zur späten Amazonischen Periode und bis hin zu den
heutigen Bedingungen zu rekonstruieren. Die hier präsentierte Forschung wurde
auf Grundlage von geomorphologischen Beobachtungen, geologischen Kartierungen,
spektroskopischen und hydraulischen Untersuchungen, sowie Altersbestimmungen
mithilfe von Bilddaten, topografischen und spektroskopischen Daten gemacht. Es
wird davon ausgegangen, dass die untersuchte Region einen der größten
Paläoseen des Mars, den Eridania See, beinhaltete. Dieser existierte während
der mittleren bis späten Noachiaschen Periode. Neue Erkenntnisse über die
Ablagerungs-, Erosions- und Verwitterungsprozesse werden ebenso dargestellt,
wie die Entwicklung der großen flüssigen Wasservorkommen der frühen Marszeit
(z.B. Eridania See) zu den fluvialen und glaziären Formen der Amazonischen
Periode. Nach dem Übergang der späten Noachischen zur frühen Hesperianischen
Periode floss der große Eridania See in das Ma`adim Valles ab und formte
einzelne geschlossene Seen. Diese isolierten Seen können während der
Hesperianischen Periode über eine geologisch lange Zeit vorhanden gewesen
sein, was hauptsächlich durch die Mächtigkeit der Sedimente und verschiedene
Alterationsprodukte bekräftigt wird. Die Anwesenheit von Material, das reich
an Fe/Mg-Schichtsilikaten, Al-Schichtsilikaten und Chloridsalzen ist, sowie
dessen stratigrafischer Vergleich, suggerieren eine chemische
Umgebungsänderung während der letzten Phase der Seen und/oder nach dessen
Austrocknung. Die geologische Karte und die Ergebnisse der Altersbestimmung
deuten darauf hin, dass die Wasservorkommen und die dazugehörigen
Verwitterungs- und Erosionsprozesse vor der frühen Amazonischen Periode
stattgefunden haben. Die Anwesenheit eines ~340 km langen Flusssystems,
welches sich auf die frühe bis mittlere Amazonische Periode datieren lässt und
sich im Südwesten der hypothetischen Uferlinie des Eridania Sees befindet,
deutet weiter darauf hin, dass das flüssige Oberflächenwasser nach
Verschwinden der isolierten Seen auf Terra Sirenum-Terra Cimmeria nicht
vollständig verschwand. Ein einzigartiger, verflochtener alluvialer Fächer,
über welchen bisher keine Berichte existieren, befindet sich im Bereich
flussabwärts des Flusssystems. Die morphologischen Beobachtungen, sowie die
hydraulische Analyse, deuten auf ein geologisch kurzes Ereignis, das wenige
bis zu einigen zehntausend Tagen für den Formationsprozess des alluvialen
Fächers im Kārūn Valles brauchte und folglich für die dazugehörigen fluvialen
Formen flussaufwärts sorgte. Die Wasserquelle ist vermutlich ein
Oberflächenausfluss, der durch die Schmelze von Eis/Schnee entstand. Diese
Erkenntnis impliziert, dass flüssiges Wasser auf der Marsoberfläche während
der frühen bis mittleren Amazonischen Periode vorhanden war. Unter den
aktuellen Klimabedingungen, welche keine dauerhafte Ansammlung von Eis/Schnee
an der Oberfläche erlauben, wurden verschiedene eisreiche Strukturen und
glaziale Strukturen auf dem Grund des beschriebenen Flusssystems beobachtet.
Die Morphologie und Stratigraphie dieser sogenannten „valley fill deposits“
(VFD) lassen auf deren Formation vor der Ablagerung des sogenannten „latitude
dependent mantle (LDM)“ schließen. Die Anwesenheit der VFD stützt die Annahme
der durch Oszillation der Planetenrotationsachse entstehenden Klimaänderungen
in den mittleren Breiten während der Amazonischen Periode. Diese Ablagerungen,
ihr Herkunftsgebiet (das Flusssystem) und die üppige fluviale Vergangenheit
der Terra Sirenum-Terra Cimmeria Region deuten darauf hin, dass Wasser
wiederholt auf der Marsoberfläche vorkam. Seine Menge nahm jedoch seit der
späten Noachischen bis zu der heutigen späten Amazonischen Epoche ab
Geologic history of water on Mars: regional evolution of aqueous and glacial processes in the southern highlands, through time
No full text
The huge potential of salt minerals deposits on Mars, to investigate the past planet’s climate and habitability
No full textOne important fraction of the sedimentary record on Mars is composed of evaporite minerals. This record has been mainly detected by orbital spectrometers (thermal, i.e., TES, THEMIS, and reflectance spectroscopy, i.e., OMEGA, CRISM) and in-situ lander and rover measurements (Viking, Pathfinder, Phoenix, MER, MSL). Moreover, the presence of alteration and saline minerals on Mars has been also detected in the SNC-type (Shergotty, Nakhla, and Chassigny) meteorites. Evaporitic minerals have most likely recorded the last presence of stable surface water on Mars. Therefore, the evaporite minerals detected across Mars, are, most probably, the last mineral assemblages to have been precipitated by ancient Martian waters. Analogue studies have shown that evaporites have the ability to preserve traces of extinct microbial life, particularly when mineralized by iron oxide; and under certain circumstances can also sustain adopted forms of extant life (i.e., halotolerant organisms). Constraining the physical and chemical conditions required to form and to preserve evaporite minerals on the surface of Mars is crucial in understanding the climate variation phases and past habitability conditions of this planet
Effects of drought on physiological and morphological features of wild and domestic Turkish watermelon genotypes
No full text10th EUCARPIA Meeting on Genetics and Breeding of Cucurbitaceae -- OCT 15-18, 2012 -- Antalya, TURKEYWOS: 000345687100038This research was carried out between 2007 and 2008 to determine drought tolerance of domestic and wild watermelon genotypes in Sanliurfa (Turkey) condition. A total of 32 wild and domestic watermelon genotypes were used in this experiment. Morphological and physiological treatments such as leaf relative-water content, leaf temperature, chlorophyll contents, leaf water potential, leaf color, leaf area, number of stomata, width of stomata, length of stomata, plant height, number of nods on the plant, plant dry matter ratio, main stem diameter, turgority and final drought resistance tests were examined. Drip irrigation treatments included complete irrigation cut off, dry (I-0), full irrigation based on replenishment of soil water depleted from 0-90 cm profile (I-1) and 50 % full irrigation (I-2). At the end of the experiment, fifteen genotypes (Kar-24, Kar-25, Kar-27, Kar-59, Kar-86, Kar-114, Kar-143, Kar-147, Kar-163, Kar-185, Kar-197, Kar-203, Kar-215, Kar-218 and Kar-224) were found as tolerant and seventeen genotypes (Kar-26, Kar-35, Kar-37, Kar-39, Kar-98, Kar-99, Kar-117, Kar-140, Kar-154, Kar-177, Kar-184, Kar-212, Kar-234, Kar-243, Kar-330, Kar-332 and Kar-325) were found as intolerant.European Assoc Res Plant Breeding, Cukurova Univ, Minis Food, Agr & Livestock, Turkish Sci & Technol Council, Antalya Tarim, Manier Seed, Yuksel Seed, Syngenta, AG Seed, Fito Seed, Multi Seed, Nunhems, Rijk Zwaan, Bati Akdeniz Agr Res Inst, Alata Hort Res StatTurkish Scientific and Technological Research Council-TUBITAKTurkiye Bilimsel ve Teknolojik Arastirma Kurumu (TUBITAK) [107T613]; Cukurova University Research FundsThe author thank to Turkish Scientific and Technological Research Council-TUBITAK (Project Number: 107T613) and Cukurova University Research Funds for their financial supports. The authors thank also to USDA-USA for their kindly help in seed supplying and Dr. I. Solmaz from Cukurova University for seed regeneration
Investigating the chloride-rich deposits in the highlands of Terra Sirenum: implication on bio-signature preservation
No full textAnnouncement of Retraction
No full textAnnouncement of Retraction
The editorial board announced this article has been retracted on May 9, 2019.
If you have any further question, please contact us at: [email protected]
Title: Assessment of Intercultural Competence as an Outcome of Internationalization in Educational Centers
Author: Solmaz Zanganeh
International Journal of Educational Technology and Learning
ISSN: 2523-0581
Volume and Number: Vol. 2, No. 2, 2018
Pages: 48-53
DOI: 10.20448/2003.22.48.5
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