12 research outputs found
Host species determines egg size in Oriental cuckoo
© 2018 The Zoological Society of London.The Oriental cuckoo Cuculus optatus is an obligate brood parasite associated with species of the genus Phylloscopus. Four distinct phenotypes of Oriental cuckoo eggs, matching eggshell colour patterns of Arctic warbler Phylloscopus borealis, common chiffchaff (Siberian) P. collybita tristis, yellow-browed warbler P. inornatus and Pallas's leaf warbler P. proregulus, have been identified in the Russian part of its breeding area. We compared egg length, breadth and volume of Oriental cuckoo egg phenotypes with eggs of the corresponding hosts from three geographical regions in Russia: the Urals, Siberia and the Far East. We found significant oometric differences between Oriental cuckoo egg phenotypes. Egg breadth of each cuckoo group matched the egg breadth of the host species, while the length of cuckoo eggs did not match egg length in host species. Our results can be explained in terms of clutch geometry. An egg sticking out above the clutch is likely to be rejected by the host and so breadth should match the host's egg. This constrains cuckoos in maintaining large egg volumes, which are essential for providing a cuckoo chick with the energy required to eject the host eggs and chicks. An increased egg length might compensate for breadth constraints. We suggest that the size of cuckoo eggs might also be affected by parental care - when only one parent is involved in feeding, eggs need to be larger. This might explain why the longest cuckoo eggs belonged to the phenotype parasitizing the smallest host, Pallas's leaf warbler, where only one parent feeds the chicks. In our view, differences in egg sizes of Oriental cuckoo phenotypes provide evidence of their adaptations to brood parasitism on small leaf warbler species.Peer reviewe
Значение макрофагов, ассоциированных с опухолью, в развитии рака мочевого пузыря
Bladder cancer is the 2nd most common urological oncological disease in the worlds. Tumors can be muscle invasive and non-muscle invasive. Recently, tumor microenvironment (TME) became a focus of investigation in malignant tumors of the bladder. According to the currently available data, TME is a specific environment crating optimal conditions for carcinogenesis in the neoplastic lesion. The main parts of TME are extracellular matrix and stroma including vasculature, stromal, and immune cells. Additionally, TME includes cytokines, chemokines, and other compounds activating signal pathways necessary for tumor cells. Tumor-associated macrophages (TAMs) are being extensively studied as representatives of TME in solid tumors of varying locations. These macrophages can be classified into 2 phenotypes: M1 (pro-inflammatory and antitumor) and M2 (anti-inflammatory and protumor). The phenotypes perform different roles, and M2 macrophages regulate the most important processes of oncogenesis (invasion, proliferation, neoangiogenesis, etc.). In the context of bladder cancer, M2 macrophages are the most significant as they are the most numerous TAMs in TME.Aim. To study the role of tumor-associated macrophages in development of bladder tumors, as well as prognostic value of these macrophages.Рак мочевого пузыря занимает 2-е место в структуре онкоурологических заболеваний во всем мире. выделяют мышечно-инвазивную и немышечно-инвазивную формы опухоли. в последнее время большое внимание уделяется изучению микроокружения опухоли (МО) при злокачественных новообразованиях мочевого пузыря. Согласно имеющимся на сегодняшний день данным, МО представляет собой специфическую среду, создающую оптимальные условия для канцерогенеза в неопластическом очаге. Основными частями МО являются внеклеточный матрикс и строма, которая включает сосуды, стромальные и иммунные клетки. помимо данных структур в состав МО входят цитокины, хемокины и другие соединения, способные обеспечивать активацию необходимых для опухолевых клеток сигнальных путей. Макрофаги, ассоциированные с опухолью (МАО), - активно изучаемые представители МО при солидных злокачественных новообразованиях различных локализаций. эти макрофаги подразделяют на 2 фенотипа: M1 (провоспалительные и противоопухолевые) и M2 (противовоспалительные и проопухолевые). Роль каждого фенотипа различна, при этом макрофаги M2 участвуют в регуляции важнейших процессов онкогенеза (инвазии, пролиферации, неоангиогенезе и т. д.). в аспекте изучения рака мочевого пузыря наибольшую значимость имеют макрофаги M2, которые являются самыми многочисленными представителями МАО в составе МО.Цель исследования - изучение роли макрофагов, ассоциированных с опухолью, в развитии злокачественных опухолей мочевого пузыря, а также их прогностической ценности
Stable isotopes and mtDNA reveal niche segregation but no evidence of intergradation along a habitat gradient in the Lesser Whitethroat complex (Sylvia curruca; Passeriformes; Aves)
Niche segregation plays a critical role in the speciation process, but determining the extent to which taxa are geographically or ecologically isolated is challenging. In this study, we use stable isotopes of carbon (δ13C), nitrogen (δ15N), hydrogen (δ2H) and oxygen (δ18O) to test for ecological differences among taxa in the Lesser Whitethroat Sylvia curruca complex. Analysis of mitochondrial DNA (mtDNA) revealed 6 distinct haplotype groups, which conform to at least 5 distinct taxa. Stable isotopes provided insight into geographical and broad-scale ecological differences among haplotypes. The most striking isotope differences were between the populations inhabiting Siberian boreal forest (S. c. blythi) from the one inhabiting semi-desert in Kazakhstan (S. c. halimodendri). It is generally assumed that these two populations form a morphological cline along a gradient from mesic to xeric habitat. Our sample includes a large proportion of morphologically intermediate individuals that appear to represent a hybrid population. However, in all of these, there is strict correspondence between haplotype and isotope signature, suggesting an ecological division on the breeding grounds between all our samples of these two taxa. The lack of ecologically intermediate individuals among our sample of morphologically intermediate ones thus speaks against the existence of a cline. The two taxa blythi and halimodendri emerge as potential models for the study of the early stages of the speciation process. While differences in stable isotopes may be largely influenced by geography, we also demonstrate how, in specific instances (such as the alleged cline reported here), they may be used to evaluate niche segregation between taxa, providing information of importance for determination of species limits
Ефективност и икономически растеж на индустриалния бизнес в съвременните условия
Преструктурирането на икономиката и утвърждаващите се пазарни условия несъмнено налагат необходимостта от формиране на нов тип икономически отношения между икономическите субекти. Повишаването на ефективността и изграждането на конкурентоспособни индустриални структури е стратегическа цел. Инвестирането в тази насока ще гарантира устойчивото и проспериращо развитие на индустриалните предприятия, непрекъснатия им икономически растеж.
Ефективността е сложна икономическа категория, валидна за всички сфери и дейности, които извършват икономическите субекти. Икономическата ефективност е индикатор за целесъобразността от използване на човешките и капиталови ресурси, т.е. за степента на оползотворяване на наличните производствени фактори.
Икономическият растеж е една от най-важните фази на икономическия цикъл. Резултат е от определени закономерности на взаимодействието между производство, разпределение и потребление на създавания продукт. Той е обективно обусловен процес, осигуряващ както задоволяването на потребностите на обществото, така и ефективността от функционирането на икономиката. Затова трябва да бъде в основата на стратегията на развитие на икономическите субекти, основна цел на тяхното управление.
Икономическият растеж се предопределя от взаимодействието между резултатите от извършваните бизнесдейности, величината на капиталовите, човешките и природни ресурси и от ефективността от тяхното използване. Затова е необходимо да се приложи система от показатели за нейното характеризиране, позволяваща не само да се оцени равнището й, но и да се изясни характера на икономическия растеж
CORRUPTION CRIMES FEATURES IN THE VOLGA FEDERAL DISTRICT
The article views the condition and basic trends of development of the operating situation in the Volga Federal District concerning the corruption crimes. The activity of law enforcement bodies in this aspect is studied. The general model of program measure for improving the law enforcement work is presented