171 research outputs found

    The ORF, Regulated Synthesis, and Persistence-Specific Variation of Influenza C Viral NS1 Protein

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    AbstractThe open reading frame (ORF) and the regulated synthesis of the influenza C viral NS1 protein were analyzed in view of viruses possessing different biological activities. We provide evidence for a 246-amino-acid NS1-ORF, encoded by five viral strains and variants. Prokaryotic expression of the prototype NS1-ORF resulted in a product of 27 kDa, confirming the predicted molecular weight. Using an antiserum raised against recombinant NS1 protein, nonstructural proteins of wild-type virus were detected in infected cells for a limited course of time, whereas a persistent virus variant was characterized by a long-term nonstructural gene expression. As examined by infection experiments, the intracellular distribution of nonstructural protein was nuclear and cytoplasmic, whereas in NS1 gene-transfected cells, the cytoplasmic localization occurred in a fine-grained structure, suggesting an analogy to influenza A viral NS1 protein. Concerning persistent infection, NS1 protein species differing in sizes and posttranslational modifications were observed for a persistent virus variant, as particularly illustrated by a high degree of NS1 phosphorylation. Virus reassortant analyses proved the importance of the NS-coding genomic segment: the minimal viral properties required for the establishment of persistence were transferred with this segment to a monoreassortant virus. Thus the influenza C viral NS1 protein is a 246-amino-acid nuclear-cytoplasmic phosphoprotein that can be subject to specific variations being functionally linked to a persistent virus phenotype

    Fiber optically integrated cost-effective spectrometer for optical coherence tomography

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    A tilted fiber Bragg grating (TFBG) was integrated as the dispersive element in a high performance biomedical imaging system. The spectrum emitted by the 23 mm long active region of the fiber is projected through custom designed optics consisting of a cylindrical lens for vertical beam collimation and successively by an achromatic doublet onto a linear detector array. High resolution tomograms of biomedical samples were successfully acquired by the frequency domain OCT-system. Tomograms of ophthalmic and dermal samples obtained by the frequency domain OCT-system were obtained achieving 2.84 μm axial and 10.2 μm lateral resolution. The miniaturization reduces costs and has the potential to further extend the field of application for OCT-systems in biology, medicine and technology

    Enzyme Scaffolds with Hierarchically Defined Properties via 3D Jet Writing

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    The immobilization of enzymes into polymer hydrogels is a versatile approach to improve their stability and utility in biotechnological and biomedical applications. However, these systems typically show limited enzyme activity, due to unfavorable pore dimensions and low enzyme accessibility. Here, 3D jet writing of water‐based bioinks, which contain preloaded enzymes, is used to prepare hydrogel scaffolds with well‐defined, tessellated micropores. After 3D jet writing, the scaffolds are chemically modified via photopolymerization to ensure mechanical stability. Enzyme loading and activity in the hydrogel scaffolds is fully retained over 3 d. Important structural parameters of the scaffolds such as pore size, pore geometry, and wall diameter are controlled with micrometer resolution to avoid mass‐transport limitations. It is demonstrated that scaffold pore sizes between 120 µm and 1 mm can be created by 3D jet writing approaching the length scales of free diffusion in the hydrogels substrates and resulting in high levels of enzyme activity (21.2% activity relative to free enzyme). With further work, a broad range of applications for enzyme‐laden hydrogel scaffolds including diagnostics and enzymatic cascade reactions is anticipated.In this article, the development and application of a water‐based bioink with preloaded enzymes is described. With 3D jet writing, a hydrodynamic jetting system, freestanding 3D hydrogel frameworks with defined micropores are brightened. The enzyme‐loaded scaffolds show a high enzymatic activity and can be tested for industrial use in a continuous flow reactor over several days.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/162721/2/mabi202000154_am.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/162721/1/mabi202000154.pd

    Cost-effective optical coherence tomography spectrometer based on a tilted fiber Bragg grating

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    A compact, fiber-based spectrometer for biomedical application utilizing a tilted fiber Bragg grating (TFBG) as integrated dispersive element is demonstrated. Based on a 45° UV-written PS750 TFBG a refractive spectrometer with 2.06 radiant/μm dispersion and a numerical aperture of 0.1 was set up and tested as integrated detector for an optical coherence tomography (OCT) system. Featuring a 23 mm long active region at the fiber the spectrum is projected via a cylindrical lens for vertical beam collimation and focused by an achromatic doublet onto the detector array. Covering 740 nm to 860 nm the spectrometer was optically connected to a broadband white light interferometer and a wide field scan head and electronically to an acquisition and control computer. Tomograms of ophthalmic and dermal samples obtained by the frequency domain OCT-system were obtained achieving 2.84 μm axial and 7.6 μm lateral resolution

    Chapter 6 Kindergarten educators’ affective-motivational dispositions

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    Affective-motivational dispositions regarding the fostering of mathematics are an important aspect of early educators' professional competence, as educators are not following curricular programmes but need to seize moments in everyday activities and in play in order to foster mathematics. A variety of scales measuring variables of affective-motivational dispositions within a questionnaire were employed in a binational study involving 132 kindergarten educators in Germany and Switzerland. Based on the expectancy-value theory of motivation, the relations between educators' emotions regarding mathematics at school, the enthusiasm for mathematics as a subject, the value placed on mathematics and the expectancy of fostering mathematics successfully (self-efficacy) as well as the enthusiasm for fostering mathematics in kindergarten are examined. Following the analysis of correlations and the testing of a multiple regression model, it was found that enthusiasm for mathematics as a subject, importance of mathematics as a subject in kindergarten and self-efficacy predict enthusiasm for fostering mathematics, whereas the variable emotions regarding mathematics at school does not increase the variance explained. Self-efficacy, importance given to mathematics and enthusiasm for fostering mathematics are slightly higher in Switzerland than in Germany, which could be interpreted in light with the structural differences regarding kindergarten

    Horizontal acquisition of a patchwork Calvin cycle by symbiotic and free-living Campylobacterota (formerly Epsilonproteobacteria).

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    Assie A, Leisch N, Meier DV, et al. Horizontal acquisition of a patchwork Calvin cycle by symbiotic and free-living Campylobacterota (formerly Epsilonproteobacteria). The ISME journal. 2019;14(1):104-122.Most autotrophs use the Calvin-Benson-Bassham (CBB) cycle for carbon fixation. In contrast, all currently described autotrophs from the Campylobacterota (previously Epsilonproteobacteria) use the reductive tricarboxylic acid cycle (rTCA) instead. We discovered campylobacterotal epibionts ("Candidatus Thiobarba") of deep-sea mussels that have acquired a complete CBB cycle and may have lost most key genes of the rTCA cycle. Intriguingly, the phylogenies of campylobacterotal CBB cyclegenes suggest they were acquired in multiple transfers from Gammaproteobacteria closely related to sulfur-oxidizing endosymbionts associated with the mussels, as well as from Betaproteobacteria. We hypothesize that "Ca. Thiobarba" switched from the rTCA cycle to a fully functional CBB cycle during its evolution, by acquiring genes from multiple sources, including co-occurring symbionts. We also found key CBB cycle genes in free-living Campylobacterota, suggesting that the CBB cycle may be more widespread in this phylum than previously known. Metatranscriptomics and metaproteomics confirmed high expression of CBB cycle genes in mussel-associated "Ca. Thiobarba". Direct stable isotope fingerprinting showed that "Ca. Thiobarba" has typical CBB signatures, suggesting that it uses this cycle for carbon fixation. Our discovery calls into question current assumptions about the distribution of carbon fixation pathways in microbial lineages, and the interpretation of stable isotope measurements in the environment

    Morphology, processes and geohazards of giant landslides in and around Agadir Canyon, northwest Africa - Cruise MSM32 - September 25 - October 30, 2013 - Bremen (Germany) - Cádiz (Spain)

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    Agadir Canyon is one of the largest submarine canyons in the World, supplying giant submarine sediment gravity flows to the Agadir Basin and the wider Moroccan Turbidite System. While the Moroccan Turbidite System is extremely well investigated, almost no data from the source region, i.e. the Agadir Canyon, are available. Understanding why some submarine landslides remain as coherent blocks of sediment throughout their passage downslope, while others mix and disintegrate almost immediately after initial failure, is a major scientific challenge, which was addressed in the Agadir Canyon source region during Cruise MSM32. We collected ~ 1500 km of seismic 2D-lines in combination with a dense net of hydroacoustic data. About 1000 km2 of sea floor were imaged during three deployments of TOBI (deep-towed sidescan sonar operated by the National Oceanography Centre Southampton). A total of 186 m of gravity cores and several giant box cores were recovered at more than 50 stations. CTD casts were collected at nine stations including one 13 hour Yo-yo CTD. The new data show that Agadir canyon is the source area of the world's largest submarine sediment flow, which occurred about 60,000 years ago. Up to 160 km3 of sediment was transported to the deep ocean in a single catastrophic event. For the first time, sediment flows of this scale have been tracked along their entire flow pathway. A major landslide area was identified south of Agadir Canyon. Landslide material enters Agadir canyon in about 2500 m water depth; the material is transported as debrite for at least another 200 km down the canyon. Initial data suggest that the last major slide from this source entered Agadir canyon at least 130,000 years ago. Living deep-water corals were recovered from a large mound field north of Agadir canyon. To our knowledge, these are the first living cold water corals recovered off the coast of Morocco (except for the Gulf of Cadiz). They represent an important link between the known cold-water coral provinces off Mauritania and in the Gulf of Cádiz
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