57 research outputs found

    Dynamic force microscopy for imaging of viruses under physiological conditions

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    Dynamic force microscopy (DFM) allows imaging of the structure and the assessment of the function of biological specimens in their physiological environment. In DFM, the cantilever is oscillated at a given frequency and touches the sample only at the end of its downward movement. Accordingly, the problem of lateral forces displacing or even destroying bio-molecules is virtually inexistent as the contact time and friction forces are reduced. Here, we describe the use of DFM in studies of human rhinovirus serotype 2 (HRV2) weakly adhering to mica surfaces. The capsid of HRV2 was reproducibly imaged without any displacement of the virus. Release of the genomic RNA from the virions was initiated by exposure to low pH buffer and snapshots of the extrusion process were obtained. In the following, the technical details of previous DFM investigations of HRV2 are summarized

    The Compact Linear Collider (CLIC) - 2018 Summary Report

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    Collective cell migration and metastases induced by an epithelial-to-mesenchymal transition in Drosophila intestinal tumors.

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    Metastasis underlies the majority of cancer-related deaths yet remains poorly understood due, in part, to the lack of models in vivo. Here we show that expression of the EMT master inducer Snail in primary adult Drosophila intestinal tumors leads to the dissemination of tumor cells and formation of macrometastases. Snail drives an EMT in tumor cells, which, although retaining some epithelial markers, subsequently break through the basal lamina of the midgut, undergo a collective migration and seed polyclonal metastases. While metastases re-epithelialize over time, we found that early metastases are remarkably mesenchymal, discarding the requirement for a mesenchymal-to-epithelial transition for early stages of metastatic growth. Our results demonstrate the formation of metastases in adult flies, and identify a key role for partial-EMTs in driving it. This model opens the door to investigate the basic mechanisms underlying metastasis, in a powerful in vivo system suited for rapid genetic and drug screens

    The Compact Linear Collider (CLIC) - 2018 Summary Report

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    The Compact Linear Collider (CLIC) is a TeV-scale high-luminosity linear e+ee^+e^- collider under development at CERN. Following the CLIC conceptual design published in 2012, this report provides an overview of the CLIC project, its current status, and future developments. It presents the CLIC physics potential and reports on design, technology, and implementation aspects of the accelerator and the detector. CLIC is foreseen to be built and operated in stages, at centre-of-mass energies of 380 GeV, 1.5 TeV and 3 TeV, respectively. CLIC uses a two-beam acceleration scheme, in which 12 GHz accelerating structures are powered via a high-current drive beam. For the first stage, an alternative with X-band klystron powering is also considered. CLIC accelerator optimisation, technical developments and system tests have resulted in an increased energy efficiency (power around 170 MW) for the 380 GeV stage, together with a reduced cost estimate at the level of 6 billion CHF. The detector concept has been refined using improved software tools. Significant progress has been made on detector technology developments for the tracking and calorimetry systems. A wide range of CLIC physics studies has been conducted, both through full detector simulations and parametric studies, together providing a broad overview of the CLIC physics potential. Each of the three energy stages adds cornerstones of the full CLIC physics programme, such as Higgs width and couplings, top-quark properties, Higgs self-coupling, direct searches, and many precision electroweak measurements. The interpretation of the combined results gives crucial and accurate insight into new physics, largely complementary to LHC and HL-LHC. The construction of the first CLIC energy stage could start by 2026. First beams would be available by 2035, marking the beginning of a broad CLIC physics programme spanning 25-30 years

    State budget of Ukraine: comparative aspect

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    Стаття присвячена визначенню того, який досвід може перейняти Україна у німецького Бюджетного кодексу, а також які функції та завдання Бюджетний кодекс України може сформувати для себе та впровадити у практику механізму державного бюджетування за допомогою візуалізації базових засад державного бюджету України.The article is devoted to determining what experience Ukraine can adopt from the German Budget Code, as well as what functions and tasks the Budget Code of Ukraine can form for itself and implement into the practice of the state budgeting mechanism by visualizing the basic principles of the state budget of Ukraine

    Digression on membrane electroporation for drug and gene delivery.

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    Neumann E, Kakorin S. Digression on membrane electroporation for drug and gene delivery. Technol Cancer Res Treat. 2002;1(5):329-339.Membrane electroporation (ME) defines an electrical technique to render lipid membranes porous and permeable, transiently and reversibly, by external voltage pulses. Although there are numerous applications of ME to manipulate cells, organelles and tissues in cell biology, biotechnology and medicine, yet the molecular mechanism of ME is only slowly being understood. A general chemical- thermodynamical approach for the quantitative description of cell membrane electroporation has been developed to provide the framework to quantitatively rationalize electroporative cell transformation and electroporative uptake of drug-like dyes into cells, as well as electrolyte efflux from salt-filled electroporated vesicles. Mechanistically, the electroporative transfer of gene and drug-like dyes involves the coupling between an interactive contact formation of the permeates with the cell surface membrane and the structural electroporation-resealing cycle C (P) where C is the closed and (P) represents a number of different porated membrane states, respectively. The experimentally accessible concentration fraction f(p) = [(P)] / ([C] + [(P)]) of porous states is related to thermodynamic and electro-mechanic parameters such as temperature and the electric field strength, membrane rigidity or curvature. The results of the theoretical approach, mainly based on electrooptical data of lipid vesicles, have been successfully used to analyze single cells and to specify conditions for the practical purpose of direct electroporative gene transfer and drug delivery, in particular in the new medical disciplines of electroporative chemotherapy and electroporative gene vaccination

    Radical telomerization of ethylene by diethyl carbonate

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    Enhanced Ligand-Based Luminescence in Metal-Organic Framework Sensor

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    SSCI-VIDE+ING+ALE:JEC:DFAInternational audienceMetal-organic frameworks are appealing hybrid solids which attract continuously growing interest. Their advantageous application in sensing devices is demonstrated here. In particular, the use of a short-pulse laser excitation of luminescent metal-organic framework is reported for the first time to favor the ligand-based emission. The designed MOF-based system achieves in vitro H2S dosing by turn-on fluorescence with unprecedented sensitivity. The Al-MIL-101-based sensor detects sulfide produced by living cells and sulfide-releasing molecules in physiological media with a constant accuracy at sub-micromolar levels. The reported sensitivity is suitable for medical applications and opens new perspectives in the design of new point-of-care testing devices. The detailed relationship between photoluminescence mechanisms and chemical modification of the MOF upon sensing is also reported
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