Publications by authors named "Pospisil J"

Article Synopsis
  • Some animals can remember important details about when and where they found food, which is called 'WWW' memory.
  • Researchers wanted to see if young kids, like 3- to 5-year-olds, could also use this type of memory in a similar way without lots of talking.
  • They found that younger kids had a hard time making choices based on memory because they didn't understand that food can go bad over time, but older kids (7 years and up) started to show better memory and decision-making skills.
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The unconventional superconductor UTe[Formula: see text] exhibits numerous signatures of spin-triplet superconductivity-a rare state of matter which could enable quantum computation protected against decoherence. UTe[Formula: see text] possesses a complex phase landscape comprising two magnetic field-induced superconducting phases, a metamagnetic transition to a field-polarized state, along with pair- and charge-density wave orders. However, contradictory reports between studies performed on UTe[Formula: see text] specimens of varying quality have severely impeded theoretical efforts to understand the microscopic origins of the exotic superconductivity.

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The development of 3D organoids has provided a valuable tool for studying human tissue and organ development in vitro. Cerebral organoids, in particular, offer a unique platform for investigating neural diseases. However, current methods for generating cerebral organoids suffer from limitations such as labor-intensive protocols and high heterogeneity among organoids.

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Bacteriophages are the most abundant biological entities on Earth, but our understanding of many aspects of their lifecycles is still incomplete. Here, we have structurally analysed the infection cycle of the siphophage Casadabanvirus JBD30. Using its baseplate, JBD30 attaches to Pseudomonas aeruginosa via the bacterial type IV pilus, whose subsequent retraction brings the phage to the bacterial cell surface.

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In this study, we present a high-resolution dataset and bioinformatic analysis of the proteome of Bacillus subtilis 168 trp+ (BSB1) during germination and spore outgrowth. Samples were collected at 14 different time points (ranging from 0 to 130 min) in three biological replicates after spore inoculation into germination medium. A total of 2191 proteins were identified and categorized based on their expression kinetics.

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UTe_{2} is a spin-triplet superconductor candidate for which high quality samples with long mean free paths have recently become available, enabling quantum oscillation measurements to probe its Fermi surface and effective carrier masses. It has recently been reported that UTe_{2} possesses a 3D Fermi surface component [Phys. Rev.

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Since its discovery, the Julia-Kocienski olefination reaction has over past 30 years become one of the key C-C connective methods that is used in late-stage natural product synthesis. The reaction proceeds under mild reaction conditions, with a wide substrate scope and functional group tolerance range and with high () selectivity. In this focused review, we discuss the reaction from a mechanistic point of view and disclose key features that play an important role in reaction selectivity.

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The enantioselective addition of isoxazolidin-5-ones to the β-carbon of allenoates has been carried out by using a novel spirobiindane-based quaternary ammonium salt catalyst. This protocol, which proceeds under classical liquid-solid phase-transfer conditions, gives access to unprecedented highly functionalized β-amino acid derivatives with good enantioselectivities and in high yields, and further manipulations of these products have been carried out as well.

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During sporulation, Bacillus subtilis forms an asymmetric septum, dividing the cell into two compartments, a mother cell and a forespore. The site of asymmetric septation is linked to the membrane where FtsZ and SpoIIE initiate the formation of the Z-ring and the E-ring, respectively. These rings then serve as a scaffold for the other cell division and peptidoglycan synthesizing proteins needed to build the septum.

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Correlative light and electron microscopy (CLEM) is an important tool for the localisation of target molecule(s) and their spatial correlation with the ultrastructural map of subcellular features at the nanometre scale. Adoption of these advanced imaging methods has been limited in plant biology, due to challenges with plant tissue permeability, fluorescence labelling efficiency, indexing of features of interest throughout the complex 3D volume and their re-localization on micrographs of ultrathin cross-sections. Here, we demonstrate an imaging approach based on tissue processing and embedding into methacrylate resin followed by imaging of sections by both, single-molecule localization microscopy and transmission electron microscopy using consecutive CLEM and same-section CLEM correlative workflow.

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Super-resolution techniques expand the abilities of researchers who have the knowledge and resources to either build or purchase a system. This excludes the part of the research community without these capabilities. Here we introduce the openSIM add-on to upgrade existing optical microscopes to Structured Illumination super-resolution Microscopes (SIM).

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σ factors are considered as positive regulators of gene expression. Here we reveal the opposite, inhibitory role of these proteins. We used a combination of molecular biology methods and computational modeling to analyze the regulatory activity of the extracytoplasmic σ factor from Streptomyces coelicolor.

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The heavy fermion paramagnet UTe exhibits numerous characteristics of spin-triplet superconductivity. Efforts to understand the microscopic details of this exotic superconductivity have been impeded by uncertainty regarding the underlying electronic structure. Here we directly probe the Fermi surface of UTe by measuring magnetic quantum oscillations in pristine quality crystals.

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CrI represents one of the most important van der Waals systems on the route to understanding 2D magnetic phenomena. Being arranged in a specific layered structure, it also provides a unique opportunity to investigate structural transformations in dimension-confined systems. CrI is dimorphic and possesses a higher symmetry low-temperature phase, which is quite uncommon.

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We report on single crystal growth of laser material Nd:YAG widely used in the applications by the innovative crucible-free floating zone method implemented in an advanced laser optical furnace. We have optimized the parameters for the production of high-quality single crystals of the size typical for laser rods. To reduce the strain and improve machinability, we have developed an afterheater to thermalize the grown part of a single crystal below the hot zone, which is a technique unavailable in common mirror furnaces.

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The existence of the V-ion orbital moment is an open issue of the nature of magnetism in the van der Waals ferromagnet VI. The huge magnetocrystalline anisotropy in conjunction with the significantly reduced ordered magnetic moment compared to the spin-only value provides strong but indirect evidence of a large V orbital moment. We used the unique capability of X-ray magnetic circular dichroism to determine the orbital component of the total magnetic moment and provide a direct proof of an exceptionally sizable orbital moment of the V ion in VI.

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Article Synopsis
  • The study uses a combination of infrared, terahertz, and Raman spectroscopies along with DFT calculations to analyze the magnetic and structural properties of a material referred to as VI, particularly focusing on changes around 79 K.
  • A significant structural transition occurs at 79 K, revealing strong ferromagnetic fluctuations below this temperature and suggesting the potential for long-range ferromagnetic order influenced by magnetoelastic coupling.
  • Below 50 K, new Raman modes appear, indicating a close relationship between structural changes and magnetic transitions, and the discovery of a THz magnon in the spectra highlights the potential of VI in the field of ultrafast THz spintronics, traditionally dominated by antiferromagnet materials.
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Many dynamic interactions within the cell microenvironment modulate cell behavior and cell fate. However, the pathways and mechanisms behind cell-cell or cell-extracellular matrix interactions remain understudied, as they occur at a nanoscale level. Recent progress in nanotechnology allows for mimicking of the microenvironment at nanoscale ; electron-beam lithography (EBL) is currently the most promising technique.

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The alarming rise of bacterial antibiotic resistance requires the development of new compounds. Such compounds, lipophosphonoxins (LPPOs), were previously reported to be active against numerous bacterial species, but serum albumins abolished their activity. Here we describe the synthesis and evaluation of novel antibacterial compounds termed LEGO-LPPOs, loosely based on LPPOs, consisting of a central linker module with two attached connector modules on either side.

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Sulfated phenolic acids are widely occurring metabolites in plants, including fruits, vegetables and crops. The untargeted UHPLC-QTOF-MS metabolomics of more than 50 samples from plant, fungi and algae lead to the discovery of a small group of sulfated metabolites derived from phenolic acids. These compounds were detected in land plants for the first time.

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Most transition-metal trihalides are dimorphic. The representative chromium-based triad, CrCl, CrBr, CrI, is characterized by the low-temperature (LT) phase adopting the trigonal BiI-type while the structure of the high-temperature (HT) phase is monoclinic of AlCltype (2/). The structural transition between the two crystallographic phases is of the first-order type with large thermal hysteresis in CrCland CrI.

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Methylammonium lead bromide is a very perspective hybrid semiconductor material, suitable for high-sensitive, filter-free photodetection of electromagnetic radiation. Herein, we studied the effect of electrode spacing on the output performance and stability of planar-type photodetectors based on high-quality MAPbBr single crystals. Such crystals, as large as 4.

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Heteroaryl sulfonamides are important structural motifs in the medicinal and agrochemical industries. However, their synthesis often relies on the use of heteroaryl sulfonyl chlorides, which are unstable and toxic reagents. Herein, we report a protocol that allows direct oxidative coupling of heteroaryl thiols and primary amines, readily available and inexpensive commodity chemicals.

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The last decade has transformed wireless access technologies and crystallized a new direction for the internet of things (IoT). The modern low-power wide-area network (LPWAN) technologies have been introduced to deliver connectivity for billions of devices while keeping the costs and consumption low, and the range of communication high. While the 5G (fifth generation mobile network) LPWAN-like radio technologies, namely NB-IoT (narrowband internet of things) and LTE-M (long-term evolution machine type communication) are emerging, the long-range wide-area network (LoRaWAN) remains extremely popular.

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