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.
Pollen plants are investigated
The situation in phenology is discussed
Problems of phenological observations in Russia
The dynamics of the dates of the onset of phenological events such as the arrival of starlings (Sturnus vulgaris L.), the first cuckoo song (Cuculus canorus), the appearance of the first birch leaves (Betula verrucosa Ehrh.), the bird cherry (Padus racemosa Lam.) and the very early flowering of the rowan (Sorbus aucuparia L.) allows us to conclude that there is an increasing trend in the duration of spring, while the duration of the fall season for the period from 1967 to 2010 is practically unchanged. For the beginning of bird cherry flowering, the offset of the trend to earlier dates is more typical for the forest and forest-steppe territories of the Russian Plain, what suggests the connection between climatic parameters. For the appearance of the first birch leaves, the multi-directional trends of the offset of dates is obvious and revealed no dependence on natural conditions and physiographical position. The advanced arrival of starlings and the start of cuckoo song cannot be used as reliable indicators. No reaction to the unique weather conditions was demonstrated by birds. It is possible that the mechanisms of migration of birds are more likely caused by the presence or absence of prey and endogenous biological rhythms.
The problems of Climate Change and phenology are discussed
The phenological tendencies in Russien plain nature are discussed
The study addresses changes in the phenological characteristics of common birch (silver birch), bird cherry, mountain ash (rowan), and small-leaves lime (linden) in the central part of European Russia (ER) on the basis of multiyear observations of the beginning of the first leaves unfolding phase for birches and the flowering phase for bird cherry, mountain ash, and linden in the period since 1976 and until 2015 (the period of most intense modern warming in Russia). Overall, the current climate change affects the phenology of all these species; however, various species demonstrate spatial and calendar differences in their phenological reactions. Bird cherry and rowan do not demonstrate significant trends in their flowering dates (or weak positive values of the linear trend coefficient) in territories located between 52° and 54° N. To the north and south of that area, the value of the coefficient is negative: up to –1.5 days/10 years for cherry, and up to and 1.0 days/10 years for rowan. However, for linden, the area of positive values extends northwards to 56° N. The discrepancies in the trends of phenological stages and trends of dates of the stable transition of the air temperature across threshold values close to the phenological stages are 2 – 10 for birch, bird cherry and rowan and up to 8–25 times for linden. A similar correlation has been observed between the phenological trends and sums of active temperatures. This demonstrates the work of adaptation homeostatic mechanisms in the plants in response to the climate change.
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.