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51.
记述了采自萨哈林岛1新种,Alopecosa mikhailovi sp.nov.,2♂♂,新种与solivaga种团近似. 相似文献
52.
Yuri M. Marusik Ahmad Nadimi Mikhail M. Omelko Seppo Koponen 《Zoology in the Middle East.》2013,59(3):255-266
This paper reports seven species found in Shirabad Cave located in the western part of Golestan Province and two species found nearby. Three families: Anyphaenidae, Segestriidae and Theridiosomatidae, and one species, Metellina merianae (Scopoli, 1763) are recorded from Iran for the first time. Two species are described as new: Tegenaria zamanii Marusik & Omelko, sp.n. (♀) and Segestria mirshamsii Marusik & Omelko, sp.n. (♀). Four species: Lepthyphantes iranicus Saaristo & Tanasevitch, 1996, Metellina merianae, Octonoba yesoensis (Saito, 1934) and Pholcus sp. are illustrated. Uloborus georgicus Mcheidze, 1997 from Eastern Georgia is synonymized with Octonoba yesoensis. The distribution of all species treated in the paper is briefly discussed, with emphasis on the easternmost records.http://www.zoobank.org/urn:lsid:zoobank.org:pub:614A0FF0-40B0-4A7E-B2B8-C6B117A80AFE 相似文献
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54.
The threat of the new pandemic influenza A(H1N1)pdm09 imposed a heavy burden on the public health system in Finland in 2009-2010. An extensive vaccination campaign was set up in the middle of the first pandemic season. However, the true number of infected individuals remains uncertain as the surveillance missed a large portion of mild infections. We constructed a transmission model to simulate the spread of influenza in the Finnish population. We used the model to analyse the two first years (2009-2011) of A(H1N1)pdm09 in Finland. Using data from the national surveillance of influenza and data on close person-to-person (social) contacts in the population, we estimated that 6% (90% credible interval 5.1 – 6.7%) of the population was infected with A(H1N1)pdm09 in the first pandemic season (2009/2010) and an additional 3% (2.5 – 3.5%) in the second season (2010/2011). Vaccination had a substantial impact in mitigating the second season. The dynamic approach allowed us to discover how the proportion of detected cases changed over the course of the epidemic. The role of time-varying reproduction number, capturing the effects of weather and changes in behaviour, was important in shaping the epidemic. 相似文献
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56.
Mariya M. Mikhailova Andrey A. Panteleyev Mikhail A. Paltsev Andrey A. Panteleyev 《Cell biology international》2019,43(10):1193-1200
It is a well‐known fact, that there is a close interconnection between vascular and neural structures in both embryonic development and postnatal life. Different models have been employed to dissect the mechanisms of these interactions, ranging from in vitro systems (e.g., co‐culture of neural and endothelial cells) to in vivo imaging of central neural system recovery in laboratory animals after artificially induced trauma. Nevertheless, most of these models have serious limitations. Here, we describe an ex vivo model, representing an organotypic co‐culture of aortic fragments (AF) with longitudinal slices of mouse neonatal spinal cord (SC) or dorsal root ganglia (DRG). The samples were co‐cultured in a medium adapted for SC tissue and lacking any pro‐angiogenic or neurotrophic growth factors. It was found, that cultivation of AFs in the SC injury zone (transversal dissection of a SC slice) resulted in the initiation of active aortic sprouting. Remarkably, the endothelial cells exiting the AFs never invaded the SC tissue, concentrating in a nearby area (negative taxis). In contrast, the DRGs, while also promoting the sprouting, were a target of active endothelial CD31+ cell invasion (positive taxis). Thus, the tissues of both central and peripheral nervous systems have a prominent positive effect on aortic sprouting, while the vector of endothelial cell expansion is strictly nervous‐tissue‐type dependent. The ex vivo AF co‐culture with SC or DRG appeared to be a useful and promising model for a further endeavor into the mechanisms driving the complex interactions between neural and endothelial tissues. 相似文献
57.
Mikhail V. Chester Samuel Markolf Braden Allenby 《Journal of Industrial Ecology》2019,23(5):1006-1015
For centuries, man‐made infrastructure has been viewed as separate from natural systems. Yet in the past few centuries, as the scale and scope of human activities have dramatically increased, there is accumulating evidence that natural systems are becoming increasingly, and in some cases entirely, managed by humans. The dichotomy between infrastructure and the environment is narrowing, and natural systems are increasingly becoming human design spaces. This is already apparent with the management of hydrologic systems for urban water supply, wildlife, agriculture, forests, and even the atmosphere, and we can expect management of the environment to become more so as human activities grow. Yet our infrastructure largely remains obdurate. They are designed to last for long times even as changes in the environment and technology accelerate. As such, our current infrastructure paradigms fail at the level of the complex, integrated systems and behaviors that characterize the Anthropogenic Earth. Infrastructure in the future will need to be designed for adaptive capacity and the complexities associated with techno‐environmental systems. 相似文献
58.
Michael J. Fanous Yanfen Li Mikhail E. Kandel Amr A. Abdeen Kristopher A. Kilian Gabriel Popescu 《Journal of biophotonics》2019,12(12)
The development of three‐dimensional (3D) cellular architectures during development and pathological processes involves intricate migratory patterns that are modulated by genetics and the surrounding microenvironment. The substrate composition of cell cultures has been demonstrated to influence growth, proliferation and migration in 2D. Here, we study the growth and dynamics of mouse embryonic fibroblast cultures patterned in a tissue sheet which then exhibits 3D growth. Using gradient light interference microscopy (GLIM), a label‐free quantitative phase imaging approach, we explored the influence of geometry on cell growth patterns and rotational dynamics. We apply, for the first time to our knowledge, dispersion‐relation phase spectroscopy (DPS) in polar coordinates to generate the radial and rotational cell mass‐transport. Our data show that cells cultured on engineered substrates undergo rotational transport in a radially independent manner and exhibit faster vertical growth than the control, unpatterned cells. The use of GLIM and polar DPS provides a novel quantitative approach to studying the effects of spatially patterned substrates on cell motility and growth. 相似文献
59.
Viktor Dremin Igor Kozlov Mikhail Volkov Nikita Margaryants Andrey Potemkin Evgeny Zherebtsov Andrey Dunaev Igor Gurov 《Journal of biophotonics》2019,12(6)
The dynamic light scattering methods are widely used in biomedical diagnostics involving evaluation of blood flow. However, there exist some difficulties in quantitative interpretation of backscattered light signals from the viewpoint of diagnostic information. This study considers the application of the high‐speed videocapillaroscopy (VCS) method that provides the direct measurement of the red blood cells (RBCs) velocity into a capillary. The VCS signal presents true oscillation nature of backscattered light caused by moving RBCs. Thus, the VCS signal can be assigned as a reference one with respect to more complicated signals like in laser Doppler flowmetry (LDF). An essential correlation between blood flow velocity oscillations in a separate human capillary and the integral perfusion estimate obtained by the LDF method has been found. The observation of blood flow by the VCS method during upper arm occlusion has shown emergence of the reverse blood flow effect in capillaries that corresponds to the biological zero signal in the LDF. The reverse blood flow effect has to be taken into account in interpretation of LDF signals. 相似文献
60.
Martin Frommhold Arend Heim Mikhail Barabanov Franziska Maier Ralf‐Udo Mühle Sergei M. Smirenski Wieland Heim 《Ecology and evolution》2019,9(24):14430-14441
The selection of a nest site is crucial for successful reproduction of birds. Animals which re‐use or occupy nest sites constructed by other species often have limited choice. Little is known about the criteria of nest‐stealing species to choose suitable nesting sites and habitats. Here, we analyze breeding‐site selection of an obligatory “nest‐cleptoparasite”, the Amur Falcon Falco amurensis. We collected data on nest sites at Muraviovka Park in the Russian Far East, where the species breeds exclusively in nests of the Eurasian Magpie Pica pica. We sampled 117 Eurasian Magpie nests, 38 of which were occupied by Amur Falcons. Nest‐specific variables were assessed, and a recently developed habitat classification map was used to derive landscape metrics. We found that Amur Falcons chose a wide range of nesting sites, but significantly preferred nests with a domed roof. Breeding pairs of Eurasian Hobby Falco subbuteo and Eurasian Magpie were often found to breed near the nest in about the same distance as neighboring Amur Falcon pairs. Additionally, the occurrence of the species was positively associated with bare soil cover, forest cover, and shrub patches within their home range and negatively with the distance to wetlands. Areas of wetlands and fallow land might be used for foraging since Amur Falcons mostly depend on an insect diet. Additionally, we found that rarely burned habitats were preferred. Overall, the effect of landscape variables on the choice of actual nest sites appeared to be rather small. We used different classification methods to predict the probability of occurrence, of which the Random forest method showed the highest accuracy. The areas determined as suitable habitat showed a high concordance with the actual nest locations. We conclude that Amur Falcons prefer to occupy newly built (domed) nests to ensure high nest quality, as well as nests surrounded by available feeding habitats. 相似文献