Search results for "DMA"
showing 10 items of 315 documents
Usançen der Börse und Convention der über See handelnden Kaufmannschaft in Riga: neuerdings revidirt und festgesetzt im November 1859
1860
Maximizing network capacity in an heterogeneous macro-micro cellular scenario
2011
The problem of resource allocation in cellular networks has been traditionally faced at two different levels: at the network level, in terms of frequency planning and reuse pattern design, and at the cell level, in terms of cell capacity optimizations based on channel-dependent scheduling, link adaptation, power control, and so on. While this second aspect has been deeply investigated in literature, the first aspect has been mainly faced with static or semi-dynamic reuse utilization solutions. In this paper we deal with the problem of multi-cellular resource allocation in heterogeneous OFDMA environments with reuse factor equal to 1, where base stations with different power constraints coex…
Synthesis of Enaminones-Based Benzo[d]imidazole Scaffold: Characterization and Molecular Insight Structure
2020
(E)-1-(1H-Benzo[d]imidazol-2-yl)-3-(dimethylamino)prop-2-en-1-one 2 was synthesized by one-pot synthesis protocol of 2-acetyl benzo[d]imidazole with dimethylformamide dimethylacetal (DMF-DMA) in xylene at 140 °
Detection of Signals in MC–CDMA Using a Novel Iterative Block Decision Feedback Equalizer
2022
This paper presents a technique to mitigate multiple access interference (MAI) in multicarrier code division multiple access (MC-CDMA) wireless communications systems. Although under normal circumstances the MC-CDMA system can achieve high spectral efficiency and resistance towards inter symbol interference (ISI) however when exposed to substantial nonlinear distortion the issue of MAI manifests. Such distortion results when the power amplifiers are driven into saturation or when the transmit signal experiences extreme adverse channel conditions. The proposed technique uses a modified iterative block decision feedback equalizer (IB-DFE) that uses a minimal mean square error (MMSE) receiver …
V krugu Bogočelovečeskoj kulʹtury. Iz stranic issledovanij nad žiznʹû i tvorčestvom sv. Materi Marii (Skobcovoj)
2016
The present article was written on the occasion of the 70th anniversary of the death of Mother Maria Skobtsova in Ravensbriick concentration camp. It aimed at presenting the Orthodox nuns path from a “prodigal intellectual” towards divinization. Mather Marias literary, artistic and social activity, which led to her death in a crematory furnace, is a perfect example of how to live a creative life which leads to Godmanhood.
The influence of the mean stress on fatigue life of 10HNAP steel under random loading
2001
Abstract This paper contains the results of uniaxial random load fatigue tests with different mean values performed on 10HNAP steel specimens. The experimental fatigue life was compared with the life determined according to different methods of amplitude transformation of the cycles. Cycles were counted with the rain flow algorithm and damage was cumulated with the Palmgren–Miner hypothesis. It has been shown that in the case of “symmetric” stress histories with zero expected values, the mean values of selected cycles do not strongly influence the calculated fatigue life and transformation of the cycle amplitudes; hence, no mean stress correction for cycle mean values different from zero is…
Fatigue crack propagation from a cold-worked hole
2007
Abstract The cold expansion process is widely used to enhance the fatigue life of structures with fastener holes. Various studies assert that the cold expansion improves the fatigue strength of fastener holes; however, the improvement of fatigue life is difficult to quantify. Therefore, the influence on fatigue life of cold-worked process was studied by numerical and experimental tests. Then, a parametric study on material hardening behavior and Bauschinger’s parameter was performed for several loading conditions in order to determine their effect on crack growth propagation. The results of the numerical tests have exhibited a good prediction of the fatigue life of the component.
Efectos conductuales y neuroquímicos del consumo de éxtasis y cocaína en ratones adolescentes.
2009
La 3,4-metilendioximetanfetamina (MDMA), una sustancia popularmente conocida como éxtasis, es una droga ilícita consumida habitualmente por adolescentes y adultos jóvenes. Además, el policonsumo es una práctica habitual entre los usuarios de la MDMA, siendo la cocaína una de las drogas más frecuentemente asociadas a esta sustancia. El objetivo del presente trabajo fue evaluar los efectos a corto y largo plazo que se producen tras la administración de la MDMA (5, 10, o 20 mg/kg) sola o en combinación con cocaína (25 mg/kg) en ratones adolescentes. En el estudio sobre el efecto agudo, observamos que ambas drogas administradas individual o simultáneamente incrementan la actividad motora. La do…
Binge administration of 3,4-methylenedioxymethamphetamine ("ecstasy") impairs the survival of neural precursors in adult rat dentate gyrus.
2006
3,4-Methylenedioxymethamphetamine (MDMA) is a potent stimulant and hallucinogenic drug whose ability to regulate neurogenesis in the adult has not been previously investigated. We used 5'-bromo-2-deoxyuridine (BrdU) and Ki-67 as mitotic markers, and doublecortin (DCX) as a marker of immature neurons, to study proliferation, survival and maturation of adult-generated cells in the dentate gyrus (DG) of the hippocampus following binge administration of MDMA (8 injections of 5 mg/kg at 6 h intervals). The results showed that MDMA treatment did not affect cytogenesis in the DG, but significantly decreased the survival rate of cells incorporated after 2 weeks to the granular layer of the DG by ca…
Neurochemical substrates of the rewarding effects of MDMA: implications for the development of pharmacotherapies to MDMA dependence.
2015
In recent years, studies with animal models of reward, such as the intracranial self-stimulation, self-administration, and conditioned place preference paradigms, have increased our knowledge on the neurochemical substrates of the rewarding effects of 3,4-methylenedioxymetamphetamine (MDMA) in rodents. However, pharmacological and neuroimaging studies with human participants are scarce. Serotonin [5-hydroxytryptamine (5-HT)], dopamine (DA), endocannabinoids, and endogenous opiates are the main neurotransmitter systems involved in the rewarding effects of MDMA in rodents, but other neurotransmitters such as glutamate, acetylcholine, adenosine, and neurotensin are also involved. The most impo…