Play is a play, is a play, is a play… or is it? Challenges in designing, implementing and evaluating play-based interventions.

When a social-emotional learning (SEL) intervention is implemented in an early childhood classroom, it often involves play. Some interventions even list play as its main component. However, the advocates of play arguing for the return of play in early childhood education (ECE) classrooms still have difficulty convincing the proponents of more rigorous academic instruction.

[Molecular mechanisms of male infertility: main directions of scientific research].

This review provides up-to-date information on the molecular basis of the pathogenesis of male infertility at the cellular and subcellular levels. The emphasis is on the importance of new next-generation sequencing technologies as a high-performance tool for studying the genome and epigenomic mechanisms, transcriptome, proteome and metabolome of ejaculate, and organs of the reproductive system. This methodology made it possible to identify differentially expressed metabolic and signaling pathways in fertile and infertile men that combine the genotype and phenotype of a particular individual into a single whole.

An observational approach for exploring variability in young children's regulation-related skills within classroom contexts.

Prior work has conceptualized children's executive function and self-regulation skills as relatively stable across short periods of time. Grounded in long-standing contextual theories of human development, this study introduces a new observational tool for measuring children's regulatory skills across different naturally occurring situations within early childhood classrooms. Using 460 observations of 91 children (M age = 5.

When everything new is well-forgotten old: Vygotsky/Luria insights in the development of executive functions.

The concept of "extra-cortical organization of higher mental functions" proposed by Lev Vygotsky and expanded by Alexander Luria extends cultural-historical psychology regarding the interplay of natural and cultural factors in the development of the human mind. Using the example of self-regulation, the authors explore the evolution of this idea from its origins to recent findings on the neuropsychological trajectories of the development of executive functions. Empirical data derived from the Tools of the Mind project are used to discuss the idea of using classroom intervention to study the development of self-regulation in early childhood.

[High-density lipoprotein subfractions and sex hormones in the blood plasma of men 40 to 59].

Examination of 50 males aged from 40 to 59 years showed that an increase or decrease in the level of cholesterol of high-density lipoproteins (HDLP) occurs mostly at the expense of cholesterol of the HDLP2 subfraction. Changes in the concentration of sex hormones in the blood plasma are attended by a change in the number of HDLP2 particles, evidence of which was a change in the content of HDLP2 cholesterol and phospholipids with the level of HDLP3 cholesterol and phospholipids remaining unaltered. A higher content is attended by a rise in the level of HDLP2 cholesterol and HDLP2 phospholipids.

[Changes in the quality of hormones in blood plasma and ischemic heart disease risk factors in 40--59-year-old men].

Testosterone, estradiol, hydrocortisone, total cholesterol, triglycerides, cholesterol of alpha-lipoproteins (alpha-CS) were estimated in blood plasma of 124 40--59 years old men examined in the course of an epidemyolodical study (representative selection). Content of insulin was estimated in 112 persons and of growth hormone--in 102 persons. Disbalance of steroid hormones (decrease in alpha-CS) was observed in men with one factor of risk of heart ischemic impairment.

[Content of testosterone and of different classes of lipoproteins in the blood plasma of men 40-59 years old].

The blood plasma of males aged from 40 to 59 (227 practically healthy individual and 48 persons suffering from ischemic heart disease) was tested for the content of testosterone, cholesterol, triglycerides, cholesterol of various classes of lipoproteins and the lipoprotein spectrum by electrophoresis in polyacrylamide gel. It was found that a change in the testosterone level in the blood plasma, even within the limits of physiological values, may affect the plasma lipoprotein spectrum: a decrease in the testosterone concentration is attended with an increase in the content of atherogenic (beta- and pre-beta-) pipoproteins and a decrease in the content of alpha-lipoproteins.

[Lipid composition of lipoproteins and excretion of 17-ketosteroids in coronary arteriosclerosis].

Blood plasma cholesterol and triglycides concentration lipids composition of lipoproteins as contrasted to the amount of 17-KS and their hormonally active fractions excreted were investigated in 87 patients with myocardial infarction in their history and in 49 practically healthy individuals with no clinical manifestations of ischemic heart disease. In patients with coronary atherosclerosis exhibiting normal blood plasma lipids level, the excretion of 17-KS and of their fractions did not differ from that in healthy individuals. Patients with hyperlipoproteinemia of the IIa, IIb and IV types demonstrated a significantly reduced excretion of 17-KS, etiocholanolone, androsterone and dehydroepiandrosterone.