685 research outputs found
Turkey's nuclear onset: military policy, techno-nationalism trends and defence industrial capabilities
President Recep Tayyip Erdoğan has recently stated that there is no reason why Turkey should not have nuclear warhead-tipped missiles, at a time when other nations also possess such a deterrent. The Turkish president's remarks sparked heated debates as to Ankara’s possible military policy shifts and related nuclear objectives. In the 2010s, Turkey accomplished a number of outstanding achievements in the defence sector, especially in unmanned systems development. Ankara is also pursuing a ballistic missile programme (the Bora missile) which saw its operational debut back in May 2019. However, in the short term, the Turkish defence technological and industrial base (DTIB) lacks the capacity to support military-grade nuclear proliferation, nuclear warhead design and strategic ballistic missile production. More importantly, present indicators suggest no backtrack from Turkey's non-proliferation commitments. Rather, the 'nuclear missile' rhetoric essentially highlights Ankara’s geopolitical worldview. (author's abstract
Direct and indirect exciton mixing in a slightly asymmetric double quantum well
We studied, theoretically, the optical absorption spectra for a slightly
asymmetric double quantum well (DQW), in the presence of electric and magnetic
fields. Recent experimental results for a 10.18/3.82/9.61 nm GaAs Al(_{.33}
)Ga(_{.67})As DQW show clearly the different behavior in the luminescence peaks
for the indirect exciton (IX) and left direct exciton (DX) as a function of the
external electric field. We show that the presence of a peak near the (DX)
peak, attributed to an impurity bound left (DX) in the experimental results,
could be a consequence of the non-trivial mixing between excitonic states.Comment: 8 pages and 8 figure
Role of myelin-associated NAD⁺-dependent deacetylase Sirtuin 2 in modifying axonal degeneration
Control of the Syrian airspace: Russian geopolitical ambitions and air threat assessment
Russia has mounted its anti-access/area denial (A2/AD) footprint in the Levant and also boosted the Syrian Arab Air Defense Force’s capabilities. Syrian skies now remain a heavily contested combat airspace and a dangerous flashpoint. Moreover, there is another grave threat to monitor at low altitudes. Throughout the civil war, various non-state armed groups have acquired advanced man-portable air defense systems (MANPADS), which pose a menacing challenge not only to the deployed forces, but also to commercial aviation around the world. In the face of these threats, NATO needs to draw key lessons-learned from the contemporary Russian operational art, and more importantly, to develop a new understanding in order to grasp the emerging reality in Syria. Simply put, control of the Syrian airspace is becoming an extremely crucial issue, and it will be a determining factor for the war-torn country’s future status quo. (author's abstract
Beyond Obama's red lines: the Syrian Arab Army and chemical warfare
he Syrian Arab Army's chemical warfare capacity has been a game-changer throughout the civil war. Unlike intelligence estimates, Bashar al-Assad's military planners considered these deadly weapons to be tactical arms for battlefield use, rather than last-resort strategic assets. During the reconstruction period, the West should pursue a comprehensive approach to address issues concerning Syria’s weapons of mass destruction. (Autorenreferat
Role of myelin-associated NAD+- dependent deacetylase Sirtuin 2 in modifying axonal degeneration
Why and how NATO should adapt to a new Mediterranean security environment
NATO faces a problematic threat landscape in the Mediterranean. The Alliance has to deal with hot topics that range from Russia’s robust military posture and involvement in the Syrian Civil War to ISIS terrorism and the migrant crisis. To address all of these challenges, NATO should boost its engagement with partner nations, produce a new maritime security approach, and counterbalance Moscow’s strategic foothold in the eastern Mediterranean. (Autorenreferat
Süüria põgenike algoritmilised kujutluspildid: hierarhiliste andmesuhete uurimine põgenike vaatenurgast
Väitekirja elektrooniline versioon ei sisalda publikatsiooneAndmestumine omab üha suuremat mõju nii sotsiaalsete rühmade kui ka terve ühiskonna igapäevaelu eri tahkudele, tuues kaasa uusi võimalusi ja ohte. Andmete kogumise, säilitamise ja analüüsimise oskus võimaldab mõnedel rühmadel ja institutsioonidel pakkuda tõhusamaid teenuseid, kuid samuti annab neile võimu teha teiste inimeste kohta andmepõhiseid otsuseid. Ka põgenikud puutuvad riigipiiridel nii enne kui pärast piiriületust kokku paljude andmetoimingutega, kuid neil on väga vähe sõnaõigust selle üle, milliseid andmepõhiseid otsuseid nende eest ja nende kohta langetatakse. Doktoritöö „Süüria põgenike algoritmilised kujutluspildid: Hierarhiliste andmesuhete uurimine põgenike vaatenurgast“ eesmärk on kaardistada põgenike vaatenurki andmestumisele ja nende suhet selle eri tahkudega, pöörates erilist tähelepanu algoritmidele. Seejuures vaatleb väitekiri, millisena näevad põgenikud algoritmide võimalikku kasulikkust ja varjupoolt, keskendudes agentsusele, kontekstidele ja julgeolekustamisele. Selle eesmärgi täitmiseks tugineb doktoritöö Süüria põgenikega Eestis ja Türgis tehtud intervjuude ning Süüria põgenike sotsiaalmeedias jagatud lugude analüüsile. Kuigi algoritmidel on keeruline struktuur, mis tekitab küsimusi läbipaistvuse ja vastutuse kohta, suutsid põgenikud mõtiskleda algoritmide üle lähtuvalt kultuurilistest teguritest ja isiklikust rändekogemusest. Doktoritöö tulemustest nähtub, et põgenikele suunatud andmepõhistes lahendustes on oluline arvestada põgenike arusaamade, murede ja eelistustega, et tagada õiglane ja kaasav algoritmipõhine valitsemine.Diverse aspects of life are becoming increasingly engaged with datafication creating both advantages and risks for society and social groups. The ability to collect, store, and analyze the data gives certain groups and institutions the power to provide more effective services and make decisions about other people. The thesis “Algorithmic Imaginaries of Syrian Refugees: Exploring Hierarchical Data Relations from the Perspective of Refugees” aims at exploring both the refugees’ perspectives and their relation to aspects of datafication with a specific focus on algorithms. While refugees are subject to many datafied practices at the borders, both before and after the crossings, they have very little say in the processes where data is used to make decisions for and about them. Using interviews conducted with Syrian refugees in Estonia and Turkey and the texts narrated by Syrian refugees on a social media initiative, the thesis provides an account of refugee perspectives regarding the datafication process and especially the algorithms, their potential benefits, and drawbacks by focusing on agency, contexts, and securitization. Although algorithms have complex structures that raise questions about transparency and accountability, the refugees were able to reflect on algorithms with an emphasis on cultural factors and personal trajectories. The thesis underlines the importance of including the perspectives of refugees, their concerns, and priorities in the datafied solutions aimed for refugees to ensure fair and inclusive algorithmic governance.https://www.ester.ee/record=b545166
Fetal major cardiac defects and placental dysfunction at 11-13 weeks' gestation
Objectives: To investigate the relationship between fetal major cardiac defects and markers of placental perfusion and function.
Methods: This was a prospective screening study in singleton pregnancies at 11-13 weeks’ gestation. Uterine artery pulsatility index (UTPI), serum pregnancy associated plasma protein-A (PAPP-A) and placental growth factor (PLGF) were measured and the values were converted into multiples of the normal median (MoM). Median MoM values in fetuses with isolated major cardiac defects were compared to those in fetuses without major defects.
Results: The 50,094 singleton pregnancies fulfilling the entry criteria included 49,898 pregnancies with a normal cardiac anatomy and 196 (0.39%) with major congenital cardiac defects; 73 (37.2%) with conotruncal defects, 63 (32.1%) with left ventricular outflow tract (LVOT) defects and 60 (30.6%) with valvular defects. In the group of cardiac defects, compared to controls, there was lower median PAPP-A MoM (0.81 vs 1.00, p<0.0001) and PLGF MoM (0.78 vs 1.00, p<0.0001) but no significant difference in UTPI MoM (1.01 vs 1.00, p=0.162).
Conclusions: In pregnancies with isolated major cardiac defects there is evidence of placental dysfunction in the absence of impaired placental perfusion
An aggregate quality investigation of the Meramec River gravels
This thesis represents a study which was made to evaluate and interpret the downstream variations in the quality of the Meramec River gravels as coarse aggregate for concrete. Since gravel deposits constitute a valuable resource for a region, it is desirable that extent and quality variations of these deposits are known. It was hoped that an evaluation of certain properties of the Meramec River gravels would assist in determining the value of the Meramec River as undeveloped aggregate source by indicating the relative quality of the gravels from alternate sites of the river. For the purpose of this investigation, representative samples from selected sites along the river were collected; engineering tests and petrographic analysis were conducted on those samples to evaluate their quality for concrete aggregates. Also an attempt was made to evaluate the effect of geologic conditions on the aggregate quality. It was found that gravels from the Meramec River, on the basis of their engineering properties, are a satisfy coarse aggregate source. Chert is the dominant rock type of the gravels. Petrographic examinations indicate they are potentially reactive aggregates. The results of the engineering tests showed little variation in the properties of gravel from the headwaters to the mouth. However, the lower portion of the river is judged to have the better quality aggregate. Although carbonate rocks constitute the most common bedrock in the basin, they form only a minor constituent of the gravels. Leaching and abrasion degradation are the main factors that cause the deficiency of carbonate rocks in the Meramec gravels --Abstract, page ii
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