Microtektites and mass extinctions: evidence for a late devonian asteroid impact

Glass spherules, similar to microtektites, have been found near the Frasnian-Famennian boundary (F/F) (Upper Devonian) at Senzeilles, Belgium, contemporaneous with one of the largest marine mass extinctions of the Phanerozoic. These spherules exhibit a wide range of compositions and display teardrop, dumbbell, and compound morphologies analogous to microtektites. In addition, they lack crystallites, have few or no vesicles, and have a low content of volatile material. These characteristics are supportive of an impact origin. The Siljan Ring (Sweden) and Charlevoix structure (Quebec,Canada) are candidate craters of this age. The presence of microtektites near the F/F boundary supports the hypothesis that an impact caused the Upper Devonian worldwide benthic mass extinctions.     

Regularities of cesium-137 elimination from sheep with the addition of the sorbent Bifezh to the ration

The parameters for eliminating ¹³⁷Cs from sheep organs and tissues with the addition of the Ferrocin-containing preparation Bifezh, making it possible to determine the time of reduction of the radionuclide content to the radiation safety standards of meat production, are established.     

A synthetic maternal-effect selfish genetic element drives population replacement in Drosophila

One proposed strategy for controlling the transmission of insect-borne pathogens uses a drive mechanism to ensure the rapid spread of transgenes conferring disease refractoriness throughout wild populations. Here, we report the creation of maternal-effect selfish genetic elements in Drosophila that drive population replacement and are resistant to recombination-mediated dissociation of drive and disease refractoriness functions. These selfish elements use microRNA-mediated silencing of a maternally expressed gene essential for embryogenesis, which is coupled with early zygotic expression of a rescuing transgene.     

The heliosphere's interstellar interaction: no bow shock

As the Sun moves through the local interstellar medium, its supersonic, ionized solar wind carves out a cavity called the heliosphere. Recent observations from the Interstellar Boundary Explorer (IBEX) spacecraft show that the relative motion of the Sun with respect to the interstellar medium is slower and in a somewhat different direction than previously thought. Here, we provide combined consensus values for this velocity vector and show that they have important implications for the global interstellar interaction. In particular, the velocity is almost certainly slower than the fast magnetosonic speed, with no bow shock forming ahead of the heliosphere, as was widely expected in the past.     

Role of nonimmune IgG bound to PfEMP1 in placental malaria

Infections with Plasmodium falciparum during pregnancy lead to the accumulation of parasitized red blood cells (infected erythrocytes, IEs) in the placenta. IEs of P. falciparum isolates that infect the human placenta were found to bind immunoglobulin G (IgG). A strain of P. falciparum cloned for IgG binding adhered massively to placental syncytiotrophoblasts in a pattern similar to that of natural infections. Adherence was inhibited by IgG-binding proteins, but not by glycosaminoglycans or enzymatic digestion of chondroitin sulfate A or hyaluronic acid. Normal, nonimmune IgG that is bound to a duffy binding-like domain beta of the P. falciparum erythrocyte membrane protein 1 (PfEMP1) might at the IE surface act as a bridge to neonatal Fc receptors of the placenta.     

Innovational trends in apple breeding and fruit quality

The innovational trends in apple breeding include the development of triploid scab immune apple cultivars. The long-term phytopathological and biological studies made it possible to develop approximately 20 first home scab immune apple cultivars and include them in the State Register of Breeding Successes. For the first time in Russia and in the world, the biological and cytoembryological studies favored the development of a number of triploid cultivars that are characterized by high marketability and better biochemical composition of fruit in comparison with well-known old cultivars and diploid scab nonimmune cultivars of VNIISPK breeding.     

Effect of soil type and overgrowth time on agrochemical parameters of fallow lands located along the accumulation trend of material–energy flow

It has been shown that changes in agrochemical parameters of fallow lands depend on the type of soil and the time of overgrowth. A gradual acidification of the postagrogenic layer, its differentiation into two sublayers by the contents of humus and total exchangeable bases, and a decrease in the content of mineral nutrients are observed in overgrown agrosoddy-podzolic soils. In agrogray soils, these processes are less intense.     

Productivity of safflower in the Caspian Coastal Arid Zone at different planting density

Oilseeds are commonly used in human nutrition, feeding farm animals, industry, construction, medicine, and perfumery. They are a valuable source of high-nutrient protein, which is contained in the oil cake and meal obtained by processing the seeds into the oil. Sunflower and mustard are traditionally cultivated in the Lower Volga Region. Safflower, camelina, and oilseed flax have not become widespread there, which can be associated with the insufficient studies of them, the lack of proven technologies for farming, and the specific biochemical composition of the oil of their seeds. The objective of the research was to study the effects of the different planting densities on the duration of the developmental interphase periods, the morphological traits, and the crop yields under the soil and climate conditions in the arid zone of the Lower Volga Region. It has been determined that the average safflower yield under such conditions can reach 1.63 t per hectare with the Astrakhanskii-747 variety at the planting density of 300000 plants per hectare.     

Inheritance of resistance to white pine blister rust on black currant and creation of donors and varieties with oligogenic control of the trait

Data are given on the inheritance of resistance to white pine blister rust by blood currant derivatives, which permit concluding oligogenic control of this trait by the dominant allele of gene Pe in the studied forms. Donors with combined resistance to white pine blister rust, powdery mildew, and gall mite are identified.     

Protective role of bioregulator stifun under the negative effect of cadmium

The effect of stifun on wheat, Welsh onion, and corn plants under the effect of cadmium is investigated. The protective effect of this bioregulator manifested itself in preventing inhibition of growth, stabilizing mitotic phases, and reducing the level of chromosomal aberrations. The results of histochemical investigations permit the assumption that growth regulators can reduce the uptake of cadmium ions into plant tissues.