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Sponges are among the most common and diverse Cambrian fossils. However, the origin of the crown groups of the extant sponge classes constitutes the principal problem in the understanding of the evolution of these lower metazoans. New intact spiculate sponges from the lower Cambrian Stage 3–Stage 4 Sinsk Lagerstätte of the Siberian Platform enable a better understanding of the early evolution of crown‐group demosponges. The skeletons of Neomenispongia plexa and N. diazoma gen. et sp. nov. consist mostly of simple oxeas, which are organized in relatively regular tufts that are additionally strengthened by sigmoidal spicules. The C‐shaped elements of N. diazoma are megascleres in their size range but have sigmoidal shapes similar to sigma microscleres of extant demosponges; the sigmoidal spicules of N. plexa fully accord with microscleres and are the smallest spicules in known Cambrian demosponges. Together with an unnamed early Cambrian demosponge from the Sirius Passet biota (Greenland) and middle Cambrian Ulospongiella from the Burgess Shale (Canada), the new species represent the earliest heteroscleromorph demosponges and indicate an evolutionary origin of microscleres from megascleres. The thin, homogenous skeleton of Keithospongos loricatus gen. et sp. nov. is built of small, spirally arranged oxeas corresponding to the skeletal structure of the primitive Hazeliidae, which have been interpreted as the ancestral skeletal organization of demosponges. These new sponges therefore provide a link from extant spiculate demosponge groups to their more familiar Cambrian ancestors. [ABSTRACT FROM AUTHOR]

The materials of the article included the following questions: operation of the FLEXTEG module in the thermoelectric generator mode; effects accompanying the thermoelectric generator and its current-voltage characteristic; the discussion of the results. The energy balance of thermal currents is estimated using the Seebeck and Thomson effects, as well as electric currents in the circuit – Peltier, and Joule-Lenz when changing the direction of their circulation. An isotropic design of a module of heat and power generators installed on an envelope flexible plate with different weights is obtained, which increases before the inflection line and decreases after it; in this case, the properties of semiconductors are independent of their location on the flexible plate. A reduction in the influence of a traveling electromagnetic bending wave on its deformation in a flexible plate has been achieved by distributing the weight of thermoelectric generators on the surface of the plate. The main factors influencing the properties of semiconductor materials and operating parameters of thermo-electric generators are estimated. The current-voltage characteristic of a thermoelectric generator with patterns of change in the intervals of voltage (0-6.0 V), current strength (0-1.4 A), power (0-4.0 W) at various temperature gradients (5, 0-105 °C), while the efficiency of thermoelectric generators was 84.0 %. [ABSTRACT FROM AUTHOR]

The paper considers a new approach to the design of preschool institutions, taking into account the psychology of children's perception. The basic principles of creating the environment, motivating children to study, developing their mental, creative and physical abilities were identified. Buildings of preschool institutions are seen as means of the world perception and social adaptation of children. The child perceives the world through visual, tactile and other sensations. All factors of changing world should be reflected in the architectural style of a building. The paper defines principles of designing preschool institutions based on numerous studies of architects and psychologists: it is proposed to create projects for children, which will function as “giant space for games” with an open plan, and child-sized friendly corners as well. It is necessary to provide visual variety of forms, to use playful elements as a part of the façade, to convert the walking paths into the playground, and also to use the ecological approach in the design.