Many environmental stimuli present a quasi-rhythmic structure at different timescales that the brain needs to decompose and integrate. Cortical oscillations have been proposed as instruments of sensory de-multiplexing, i.e., the parallel processing of different frequency streams in sensory signals. Yet their causal role in such a process has never been demonstrated. Here, we used a neural microcircuit model to address whether coupled theta–gamma oscillations, as observed in human auditory cortex, could underpin the multiscale sensory analysis of speech. We show that, in continuous speech, theta oscillations can flexibly track the syllabic rhythm and temporally organize the phoneme-level response of gamma neurons into a code that enables syllable identification. The tracking of slow speech fluctuations by theta oscillations, and its coupling to gamma-spiking activity both appeared as critical features for accurate speech encoding. These results demonstrate that cortical oscillations can be a key instrument of speech de-multiplexing, parsing, and encoding.
Climate change, water scarcity and food deficit are analyzed in the article within the frameworks of the public goods theory. Special attention is paid to the international cooperation in the given sphere. Mitigation of climate change is global public good and this makes active international collaboration possible, while resistance to water and food scarcity is global merit good that’s why the cooperation is complicated. Transition to the complex mitigation of global problems is considered to be the most efficient way to resolve them.
The article focuses on the influence of global climate change on the world economy. The author points out that this influence is broader than damage from the transformation of environment caused by climate change and involves the variety of issues including impacts on the technological progress and formation of new carbon markets. Special attention is paid to the role of intergovernmental regulation and the composition of climate policy which change as the influence of climate change grows. Climate policy passes to the national level and switches to the priority of adaptation measures.
Analysis of Climate change in Russia
Hypoxia of trophoblast cells is an important regulator of normal development of the placenta. However, some pathological states associated with hypoxia, e.g. preeclampsia, impair the functions of placental cells. Oxyquinoline derivative inhibits HIF-prolyl hydroxylase by stabilizing HIF-1 transcription complex, thus modeling cell response to hypoxia. In human choriocarcinoma cells BeWo b30 (trophoblast model), oxyquinoline increased the expression of a core hypoxia response genes along with up-regulation of NOS3, PDK1, and BNIP3 genes and down-regulation of the PPARGC1B gene. These changes in the expression profile attest to activation of the metabolic cell reprogramming mechanisms aimed at reducing oxygen consumption by enabling the switch from aerobic to anaerobic glucose metabolism and the respective decrease in number of mitochondria. The possibility of practical use of the therapeutic properties of oxyquinoline derivatives is discussed.