Spectral characteristics of vowel-like sounds in children of the first year of life and speech development

To study the continuity in speech development, an investigation of vowel-like sounds recorded in the course of longitudinal research of speech formation was carried out in 12 infants beginning with the first month up to 12 months of their life. It was revealed that features ensuring separation of vowel-like sounds are specific by their amplitude relation and frequency location of the most expressed spectral maxima, including the maxima corresponding to the fundamental frequency. As fundamental frequency increased, the vowel-like sounds [a], [u], [i] began to exhibit specific changes of the amplitude ratios of the spectral maxima. It was established that peculiarities of frequency positions of spectral maxima and relations of their amplitudes may be the very features on the bases of which children compare their own vowel-like sounds to the vowels of the adults in sound imitation. These findings and literature data corroborated the opinion of continuity in speech development, beginning with the early preverbal vocalizations.     

Effect of learning on EEG characteristics of children during the third year

Characteristics were studied of frequency spectrum and spatial-temporal organization of bioelectrical cerebral activity and also of heart rate dynamics in children of the third year of life in the state of quiet wakefulness and during orienting reaction. Changes were recorded in the parameters of the cerebral activity under the influence of developing learning and in particular of formation of symbolic thinking function. It has been established that the involvement of the child in the process of learning leads to definite shifts of the EEG of quiet wakefulness testifying to acceleration of the process of the CNS functional maturation. Mastering of a high degree of play symbolization causes not only changes in the EEG but also an increase of the child orientating-investigatory activity.     

Vocal-speech development of the child during the first year of life

The study aimed at investigation into the first step of language acquisition by Russian children and the imitation process as a possible mechanism of mastering the language through the sounds specific for their native language. On the basis of spectrographic, phonetic, and listener's analysis of the sounds infants, the beginning of shaping of the phonologic system in Russian language, was shown. It was shown that, during imitation of mother's voice, children acquire articulation skills and sound utterances approximating a phoneme category of the native language. The data obtained indicate that interaction between mother and child fulfills the function of learning transmitting a language data on the tongue trame.     

The development of human gut microbiota fermentation capacity during the first year of life

Fermentation capacity of microbial ecosystems intrinsically depends on substrate supply and the ability of a microbial community to deliver monomers for fermentation. In established microbial ecosystems, the microbial community is adapted to efficiently degrade and ferment available biopolymers which is often concurrently reflected in the richness of the microbial community and its functional potential. During the first year of life, the human gut microbial environment is a rather dynamic system that is characterized by a change in physiological conditions (e.g. from aerobic to anaerobic conditions, physical growth of the gastrointestinal tract, development of the intestinal immune system) but also by a change in nutrient supply from a compositionally limited liquid to a diverse solid diet, which demands major compositional and functional changes of the intestinal microbiota. How these transitions link to intestinal microbial fermentation capacity has gained comparatively little interest so far. This mini-review aims to collect evidence that already after birth, there is seeding of a hidden population of various fermentation organisms which remain present at low abundance until the cessation of breastfeeding removes nutritional restrictions of a liquid milk-based diet. The introduction of solid food containing plant and animal material is accompanied by an altering microbiota. The concurrent increases in the abundance of degraders and fermenters lead to higher intestinal fermentation capacity indicated by increased faecal levels of the final fermentation metabolites propionate and butyrate. Recent reports indicate that the development of fermentation capacity is an important step during gut microbiota development, as chronic disorders such as allergy and atopic dermatitis have been linked to lower degradation and fermentation capacity indicated by reduced levels of final fermentation metabolites at 1 year of age.     

Formation of intestinal microflora in children during the first year of their life

In 525 young children the state of intestinal microbiocenosis was studied every month of the first year their life. The study revealed that the process of the microflora formation lasted throughout the first year of their life and was characterized by dysbiotic disturbances. During this period the aggravation of dysbiotic changes in the intestine of these children on months 3, 6-7 and 11-12 was of particular importance. The formation of stable dysbacteriosis led to a decrease in the immunological status of the child, which was manifested by the increased content of such microorganisms as hemolytic cocci, Proteus and a decrease in the quantitative level of bifidobacteria in the total intestinal microbiocenosis by the end of the first year of child's life.     

A neurophysiologic study of sleep in children during the first year of life]

Polygraphic investigation of day sleep has been carried out in thirty suckling infants (aged from 25 days to 12 months). EEG, OCG, SGR, respiration ECG, muscular activity, and in some infants, also rheographic parameters (REG and RG of the shin) have shown that already at an early nursing age, states of drowsiness, falling asleep, light and medium depth and deep slow sleep set in, as well as the so-called rapid sleep which occurs only after slow sleep. The denotation of the slow sleep stages is based on the classification by Loomis et al., though their electroenecepholographic expression in the infant is in many ways peculiar and undergoes certain dynamics during the first year of life. Peculiarities of the central area EEG have been exhibited in all the age groups, and it has been assumed that the central parts of the cortex of a suckling infant are a kind of "window" into the subcortical parts. While EEG, displaying new forms of activity at certain stages of sleep undergo distinct age changes, vegetative sleep manifestations display only some age depending quantitative differences. Thus, at the nursing age the mechanisms of electroencephalographic and vegetative sleep manifestations are of different degree of maturity: they possess a considerable autonomy, although they function in concord.     

Perception of sounds emitted by children during the second year of life by russian-speaking listeners

The aim of this study was to investigate the characteristic of information sufficiency in speech of children during their second year of life. We tried to select those elements of child's speech which have the main meaning in successive recognition of the sense of child's utterances by adults. The vocal phonemes from child's words and syllabic structure of words in child's utterances, were quite successfully recognized. Unclear articulated consonant's phonemes caused mistakes in recognition. Auditors with professional experience of analysis of child's sounds described the phoneme consequences of child's signals and the scence of child's words more clearly.     

Multifocal periventricular leukomalacia in children up to 1 year of life

The authors present an analysis of the multifocal leucoencephalomalacia in children under 1 year of life based on the material obtained from 2.398 autopsies. It was found that 32 autopsied children suffered from this disease (1.33%). Twenty four of these children were premature. The disease was more frequent in the infants (23 cases) than in neonates (9 cases), and in boys (20 cases) than in girls (12 cases). Multifocal leucoenephalomalacia was manifested mainly as spastic infantile paralysis in the majority of the infants (14 cases). Morphological lesions to the brain most frequently embraced white substance adjacent to the cerebral ventricles (foci of leucoencephalomalacia of 1 cm in diameter) and cerebral vessels. Widening of the ventricular system of the brain was seen in 15 cases. Pathological reaction resulted from the brain anoxia and ischemia in perinatal period (20 cases) or septicaemia (12 cases) while predisposing factors included: prematurity, respiratory failure with hyaline membranes in the lungs and congenital abnormalities of the heart.     

生命的三界学说以及生命的第三形式

1997年,Woese等人用比较16SrRNA序列的方法将生物分成三大类群,即真核类群,细菌类群和古生物类群。古细菌是既不同于原核生物也不同于真核生物的第三类生物。对生物三界学说的由来和发展、古细菌的分类、研究现状以及展望作一概述。