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AbstractA subgroup X of a group G is called pronormal if X and Xg are conjugate in 〈X,Xg〉 for each element g of G. Pronormal subgroups play a relevant role in many problems of group theory; for instance, they arise naturally in the study of groups in which normality is a transitive relation, because a subgroup is normal if and only if it is subnormal and pronormal. Groups with only pronormal subgroups have been described by Kuzennyĭ and Subbotin (at least in the locally graded case) and the aim of this paper is to investigate the structure of uncountable locally graded groups of cardinality ℵ in which all subgroups of cardinality ℵ are pronormal. [ABSTRACT FROM AUTHOR]

Let 퐺 be a group. A subgroup 퐻 of 퐺 is called permutable if H ⁢ X = X ⁢ H HX=XH for all subgroups 푋 of 퐺. Permutability is not in general a transitive relation, and 퐺 is called a PT \mathrm{PT} -group if, whenever 퐾 is a permutable subgroup of 퐺 and 퐻 is a permutable subgroup of 퐾, we always have that 퐻 is permutable in 퐺. The property PT \mathrm{PT} is not inherited by subgroups, and 퐺 is called a PT ̄ \overline{\mathrm{PT}} -group if all its subgroups have the PT \mathrm{PT} -property. We prove that if 퐺 is a soluble group of infinite rank whose proper subgroups of infinite rank have the PT \mathrm{PT} -property, then 퐺 is a PT ̄ \overline{\mathrm{PT}} -group. [ABSTRACT FROM AUTHOR]

A rather natural way for trying to obtain a lattice-theoretic characterization of a class of groups ω is to replace the concepts appearing in the definition of ω by lattice-theoretic concepts. The first to use this idea were Kontorovič and Plotkin who in 1954 introduced the notion of modular chain in a lattice, as translation of a central series of a group, to determine a lattice-theoretic characterization of the class of torsion-free nilpotent groups. The aim of this paper is to present a recent application of this translation method to some generalized nilpotency properties. [ABSTRACT FROM AUTHOR]

Simple Summary: Cocaine, a widely used drug, can influence sexual behavior. It has been shown, especially in mammals, that cocaine can cause various disorders of sexual activity and gonadal dysfunction in both sexes. Cocaine has been found to alter the cell cycle, alter the meiotic spindle, induce apoptosis, and alter sperm motility. This review provides an overview of the main effects of cocaine on spermatogenesis and oogenesis, laying the groundwork for future investigations into the molecular mechanisms underlying the interaction of cocaine and its metabolites with germ cells. Cocaine is one of the most widely used drugs that, due to its molecular properties, causes various behavioral alterations, including sexual behavior. In vivo and in vitro studies conducted mainly in mammals have shown various disorders of sexual activity and morpho-functional dysfunctions of the gonads in both sexes. Although the modalities are still unclear, cocaine has been shown to alter the cell cycle, induce apoptosis, and alter sperm motility. In females, this drug alters the formation of the meiotic spindle as well as may obstruct the ovulation mechanism of mature oocytes. The data provided in this review, in addition to reviewing the current literature on the main effects of cocaine on spermatogenesis and oogenesis mainly in mammals, will hopefully provide a basic overview that may help and support further future studies on the molecular interaction of cocaine and its metabolites with germ cells. [ABSTRACT FROM AUTHOR]

Regarding the lack of studies about lotic eutrophication, mainly for tropical rivers, thisresearch aimed to assess the density of phytoplanktonic community of two tropical riverslocated in Ribeira do Iguape Watershed (São Paulo state, Brazil), Canha and Pariquera-AçuRivers, based on sampling campaigns in January and April, 2007. These results werecompared to the mTSI (mean Trophic State Index) values. This index was originallydeveloped for lentic aquatic systems and its calculus depends on total phosphorous,orthophosphate and chlorophyll-a concentrations in water samples. Comparing mTSI valuesin all sampling stations with the phytoplankton quantitative results, it was possible to verifythat mTSI may overestimate the trophic state of lotic ecosystems, since the phosphorusspecies that integrate its calculus contributed to an improper augmentation on mTSI, whichwere incompatible with the real associated biological response. Thus, for April sampling,although mTSI values were higher, in general, phytoplankton density were lower (minimumof 83 indmL-1 for Canha River and of 66 indmL-1 for Pariquera-Açu River). In this case, thehigh total phosphorous concentrations by themselves were not enough to promoteproportional phytoplanktonic growth, which was probably limited by other factors, like watertemperature, suspended solids concentration, river discharge and zooplanktonic predation. InJanuary, on the other hand, mTSI values were lower, but total phytoplankton density washigher. For this sampling, the lower orthophosphate concentrations in water pointedphytoplankton assimilation of this nutrient.