Additive decomposability of functions over abelian groups

Abelian groups are classified by the existence of certain additive decompositions of group-valued functions of several variables with arity gap 2.Comment: 17 page

Organization of international cargo transportation and basic ways of improvement transportation

This article describes and provides methods of management, organization, and improving international cargo transportation. The process of international cargo transportation and the main criteria for assessing the quality of transport service were observed. An algorithm of modeling the international transport network was suggested

On the effect of variable identification on the essential arity of functions

We show that every function of several variables on a finite set of k elements with n>k essential variables has a variable identification minor with at least n-k essential variables. This is a generalization of a theorem of Salomaa on the essential variables of Boolean functions. We also strengthen Salomaa's theorem by characterizing all the Boolean functions f having a variable identification minor that has just one essential variable less than f.Comment: 10 page

Organization of international cargo transportation and basic ways of improvement transportation

This article describes and provides methods of management, organization, and improving international cargo transportation. The process of international cargo transportation and the main criteria for assessing the quality of transport service were observed. An algorithm of modeling the international transport network was suggested

Quantitative proteomics of rat livers shows that unrestricted feeding is stressful for proteostasis with implications on life span.

Studies in young mammals on the molecular effects of food restriction leading to prolong adult life are scares. Here, we used high-throughput quantitative proteomic analysis of whole rat livers to address the molecular basis for growth arrest and the apparent life-prolonging phenotype of the food restriction regimen. Over 1800 common proteins were significantly quantified in livers of ad libitum, restriction- and re-fed rats, which summed up into 92% of the total protein mass of the cells. Compared to restriction, ad libitum cells contained significantly less mitochondrial catabolic enzymes and more cytosolic and ER HSP90 and HSP70 chaperones, which are hallmarks of heat- and chemically-stressed tissues. Following re-feeding, levels of HSPs nearly reached ad libitum levels. The quantitative and qualitative protein values indicated that the restriction regimen was a least stressful condition that used minimal amounts of HSP-chaperones to maintain optimal protein homeostasis and sustain optimal life span. In contrast, the elevated levels of HSP-chaperones in ad libitum tissues were characteristic of a chronic stress, which in the long term could lead to early aging and shorter life span

ОЦЕНКИ СКОРОСТИ СХОДИМОСТИ К АССОЦИИРОВАННЫМ РЕШЕНИЯМ ДИФФЕРЕНЦИАЛЬНЫХ УРАВНЕНИЙ С ОБОБЩЕННЫМИ КОЭФФИЦИЕНТАМИ В АЛГЕБРЕ МНЕМОФУНКЦИЙ

Systems of differential equations with generalized coefficients are investigated in the algebra of mnemofunctions. A convergence rate to associated solutions of differential equations is estimated.В работе изучаются многомерные дифференциальные уравнения с обобщенными коэффициентами в алгебре мнемофункций. Получены явные выражения для констант, определяющих скорость сходимости в пространстве интегрируемых функций к ассоциированным решениям рассматриваемых уравнений

Intrinsic Activity and Stability of Bifunctional Human UMP Synthase and Its Two Separate Catalytic Domains, Orotate Phosphoribosyltransferase and Orotidine-5′-phosphate Decarboxylase

Human UMP synthase is a bifunctional protein containing two separate catalytic domains, orotate phosphoribosyltransferase (EC 2.4.2.10) and orotidine-5'-phosphate decarboxylase (EC 4.1.1.23). These studies address the question of why the last two reactions in pyrimidine nucleotide synthesis are catalyzed by a bifunctional enzyme in mammalian cells, but by two separate enzymes in microorganisms. From existing data on subunit associations of the respective enzymes and calculations showing the molar concentration of enzyme to be far lower in mammalian cells than in microorganisms, we hypothesize that the covalent union in UMP synthase stabilizes the domains containing the respective catalytic centers. Evidence supporting this hypothesis comes from studies of stability of enzyme activity in vitro, at physiological concentrations, of UMP synthase, the two isolated catalytic domains prepared by site-directed mutagenesis of UMP synthase, and the yeast ODCase. The two engineered domains have activities very similar to the native UMP synthase, but unlike the bifunctional protein, the domains are quite unstable under conditions promoting the dissociated monomer

Genetic regulation of pituitary gland development in human and mouse

Normal hypothalamopituitary development is closely related to that of the forebrain and is dependent upon a complex genetic cascade of transcription factors and signaling molecules that may be either intrinsic or extrinsic to the developing Rathke’s pouch. These factors dictate organ commitment, cell differentiation, and cell proliferation within the anterior pituitary. Abnormalities in these processes are associated with congenital hypopituitarism, a spectrum of disorders that includes syndromic disorders such as septo-optic dysplasia, combined pituitary hormone deficiencies, and isolated hormone deficiencies, of which the commonest is GH deficiency. The highly variable clinical phenotypes can now in part be explained due to research performed over the last 20 yr, based mainly on naturally occurring and transgenic animal models. Mutations in genes encoding both signaling molecules and transcription factors have been implicated in the etiology of hypopituitarism, with or without other syndromic features, in mice and humans. To date, mutations in known genes account for a small proportion of cases of hypopituitarism in humans. However, these mutations have led to a greater understanding of the genetic interactions that lead to normal pituitary development. This review attempts to describe the complexity of pituitary development in the rodent, with particular emphasis on those factors that, when mutated, are associated with hypopituitarism in humans