9 research outputs found

    Тенденції розвитку національної інноваційної системи в Україні

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    Проаналізовано національну інноваційну систему України. Розглянуто галузі промисловості України за ознаками інноваційної активності та досліджено темпи зростання показників, враховуючи індекс інфляції. Встановлено, що спад темпів зростання динаміки реалізованої продукції призводить до зменшення витрат на інноваційну діяльність.Дан анализ национальной инновационной системы Украины. Рассмотрены отрасли промышленности Украины по признакам инновационной активности и исследованы темпы роста показателей, учитывая индекс инфляции. Установлено, что спад темпов роста динамики реализованной продукции приводит к уменьшению затрат на инновационную деятельность.This article analyses national innovation system of Ukraine. Examined the industry of Ukraine based on innovative activity and investigated the growth indicators, taking into account inflation-index. It is established that the slowdown in the dynamics realized production leads to a decrease in the cost of innovation

    Comparing strategies for deep astigmatism-based single-molecule localization microscopy

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    Single-molecule localization microscopy (SMLM) enables fluorescent microscopy with nanometric resolution. While localizing molecules close to the coverslip is relatively straightforward using high numerical aperture (NA) oil immersion (OI) objectives, optical aberrations impede SMLM deeper in watery samples. Adaptive optics (AO) with a deformable mirror (DM) can be used to correct such aberrations and to induce precise levels of astigmatism to encode the z-position of molecules. Alternatively, the use of water immersion (WI) objectives might be sufficient to limit the most dominant aberrations. Here we compare SMLM at various depths using either WI or OI with or without AO. In addition, we compare the performance of a cylindrical lens and a DM for astigmatism-based z-encoding. We find that OI combined with adaptive optics improves localization precision beyond the performance of WI-based imaging and enables deep (>10 µm) 3D localization

    Differentiation between Oppositely Oriented Microtubules Controls Polarized Neuronal Transport

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    Microtubules are essential for polarized transport in neurons, but how their organization guides motor proteins to axons or dendrites is unclear. Because different motors recognize distinct microtubule properties, we used optical nanoscopy to examine the relationship between microtubule orientations, stability, and modifications. Nanometric tracking of motors to super-resolve microtubules and determine their polarity revealed that in dendrites, stable and acetylated microtubules are mostly oriented minus-end out, while dynamic and tyrosinated microtubules are oriented oppositely. In addition, microtubules with similar orientations and modifications form bundles that bias transport. Importantly, because the plus-end-directed Kinesin-1 selectively interacts with acetylated microtubules, this organization guides this motor out of dendrites and into axons. In contrast, Kinesin-3 prefers tyrosinated microtubules and can enter both axons and dendrites. This separation of distinct microtubule subsets into oppositely oriented bundles constitutes a key architectural principle of the neuronal microtubule cytoskeleton that enables polarized sorting by different motor proteins

    Differentiation between Oppositely Oriented Microtubules Controls Polarized Neuronal Transport

    No full text
    Microtubules are essential for polarized transport in neurons, but how their organization guides motor proteins to axons or dendrites is unclear. Because different motors recognize distinct microtubule properties, we used optical nanoscopy to examine the relationship between microtubule orientations, stability, and modifications. Nanometric tracking of motors to super-resolve microtubules and determine their polarity revealed that in dendrites, stable and acetylated microtubules are mostly oriented minus-end out, while dynamic and tyrosinated microtubules are oriented oppositely. In addition, microtubules with similar orientations and modifications form bundles that bias transport. Importantly, because the plus-end-directed Kinesin-1 selectively interacts with acetylated microtubules, this organization guides this motor out of dendrites and into axons. In contrast, Kinesin-3 prefers tyrosinated microtubules and can enter both axons and dendrites. This separation of distinct microtubule subsets into oppositely oriented bundles constitutes a key architectural principle of the neuronal microtubule cytoskeleton that enables polarized sorting by different motor proteins

    Comparing strategies for deep astigmatism-based single-molecule localization microscopy

    No full text
    Single-molecule localization microscopy (SMLM) enables fluorescent microscopy with nanometric resolution. While localizing molecules close to the coverslip is relatively straightforward using high numerical aperture (NA) oil immersion (OI) objectives, optical aberrations impede SMLM deeper in watery samples. Adaptive optics (AO) with a deformable mirror (DM) can be used to correct such aberrations and to induce precise levels of astigmatism to encode the z-position of molecules. Alternatively, the use of water immersion (WI) objectives might be sufficient to limit the most dominant aberrations. Here we compare SMLM at various depths using either WI or OI with or without AO. In addition, we compare the performance of a cylindrical lens and a DM for astigmatism-based z-encoding. We find that OI combined with adaptive optics improves localization precision beyond the performance of WI-based imaging and enables deep (>10 µm) 3D localization

    Efficient switching of mCherry fluorescence using chemical caging

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    Fluorophores with dynamic or controllable fluorescence emission have become essential tools for advanced imaging, such as superresolution imaging. These applications have driven the continuing development of photoactivatable or photoconvertible labels, including genetically encoded fluorescent proteins. These new probes work well but require the introduction of new labels that may interfere with the proper functioning of existing constructs and therefore require extensive functional characterization. In this work we show that the widely used red fluorescent protein mCherry can be brought to a purely chemically induced blue-fluorescent state by incubation with β-mercaptoethanol (βME). The molecules can be recovered to the red fluorescent state by washing out the βME or through irradiation with violet light, with up to 80% total recovery. We show that this can be used to perform single-molecule localization microscopy (SMLM) on cells expressing mCherry, which renders this approach applicable to a very wide range of existing constructs. We performed a detailed investigation of the mechanism underlying these dynamics, using X-ray crystallography, NMR spectroscopy, and ab initio quantum-mechanical calculations. We find that the βME-induced fluorescence quenching of mCherry occurs both via the direct addition of βME to the chromophore and through βME-mediated reduction of the chromophore. These results not only offer a strategy to expand SMLM imaging to a broad range of available biological models, but also present unique insights into the chemistry and functioning of a highly important class of fluorophores

    Microtubule minus-end binding protein CAMSAP2 controls axon specification and dendrite development

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    In neurons, most microtubules are not associated with a central microtubule-organizing center (MTOC), and therefore, both the minus and plus-ends of these non-centrosomal microtubules are found throughout the cell. Microtubule plus-ends are well established as dynamic regulatory sites in numerous processes, but the role of microtubule minus-ends has remained poorly understood. Using live-cell imaging, high-resolution microscopy, and laser-based microsurgery techniques, we show that the CAMSAP/Nezha/Patronin family protein CAMSAP2 specifically localizes to non-centrosomal microtubule minus-ends and is required for proper microtubule organization in neurons. CAMSAP2 stabilizes non-centrosomal microtubules and is required for neuronal polarity, axon specification, and dendritic branch formation in vitro and in vivo. Furthermore, we found that non-centrosomal microtubules in dendrites are largely generated by γ-Tubulin-dependent nucleation. We propose a two-step model in which γ-Tubulin initiates the formation of non-centrosomal microtubules and CAMSAP2 stabilizes the free microtubule minus-ends in order to control neuronal polarity and development
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