Epitaxial thin films of undoped LaCoO\(_{3}\)\@, of electron-doped La\(_{0.7}\)Ce\(_{0.3}\)CoO\(_{3}\)\@, and of hole-doped La\(_{0.7}\)Sr\(_{0.3}\)CoO\(_{3}\)\@ exhibit ferromagnetic order with a ...transition temperature \(T_{\rm{C}}\) \(\approx\) 85 K, 22 K, and 240 K, respectively. The spin-state structure for these compounds was studied by soft x-ray magnetic circular dichroism at the Co \(L_{2,3}\) and O \(K\) edges. It turns out that a higher spin state of the Co\(^{3+}\) ions is responsible for the magnetism in LaCoO\(_{3}\)\@ while for La\(_{0.7}\)Ce\(_{0.3}\)CoO\(_{3}\) the Co\(^{3+}\) ions are in a low-spin state and the ferromagnetism is predominantly determined by Co\(^{2+}\)\@. For La\(_{0.7}\)Sr\(_{0.3}\)CoO\(_{3}\)\@, on the other hand, the magnetism originates from higher spin states of Co\(^{3+}\) and Co\(^{4+}\)\@. Moreover, a strong magnetic anisotropy is observed for all systems.
Summary
Magnetospirillum gryphiswaldense MSR‐1 synthesizes membrane‐enclosed magnetite (Fe3O4) nanoparticles, magnetosomes, for magnetotaxis. Formation of these organelles involves a complex process ...comprising key steps which are governed by specific magnetosome‐associated proteins. MamB, a cation diffusion facilitator (CDF) family member has been implicated in magnetosome‐directed iron transport. However, deletion mutagenesis studies revealed that MamB is essential for the formation of magnetosome membrane vesicles, but its precise role remains elusive. In this study, we employed a multi‐disciplinary approach to define the role of MamB during magnetosome formation. Using site‐directed mutagenesis complemented by structural analyses, fluorescence microscopy and cryo‐electron tomography, we show that MamB is most likely an active magnetosome‐directed transporter serving two distinct, yet essential functions. First, MamB initiates magnetosome vesicle formation in a transport‐independent process, probably by serving as a landmark protein. Second, MamB transport activity is required for magnetite nucleation. Furthermore, by determining the crystal structure of the MamB cytosolic C‐terminal domain, we also provide mechanistic insight into transport regulation. Additionally, we present evidence that magnetosome vesicle growth and chain formation are independent of magnetite nucleation and magnetic interactions respectively. Together, our data provide novel insight into the role of the key bifunctional magnetosome protein MamB, and the early steps of magnetosome formation.
Magnetotactic bacteria can navigate along geomagnetic field lines due to the formation of magnetic iron minerals within unique prokaryotic organelles called magnetosomes. Here, using a multidisciplinary approach, we show that magnetosome biogenesis relies on the bifunctionality of the essential magnetosome membrane protein MamB. Our results also demonstrate that the intracellular assembly of 1D magnetosome arrays mainly depends on biotic factors.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
This paper presents an exploratory study on the knowledge and importance of integrating Lean Education in curricula from the Academy perspective. The study was based on the analysis of participants' ...outcomes of workshops settled in international conferences. These workshops were used to promote Lean Education as a fundamental content and competency to be taught to the new professionals, independently of their future activity. Having in their DNA Lean content and competency, professionals will be thinkers adopting whole system-thinking, a sustainable conscious and ethical behaviour prepared to face Fourth industrial revolution demands. The authors believe that Lean Education provides such competencies to the new professionals and have been settling and operationalized such workshops in different contexts, involving more than 100 participants (mainly, academics) with teaching responsibilities in training the future workforce. Workshops outcomes were obtained from participants' active discussions and through a satisfaction assessment questionnaire filled by all participants at the end of the workshop. Results show that Lean Education is valuable by academics (more than 50% of the participants gave a high score to the practicality, value, and timeliness of the workshop contents). Nevertheless, a small percentage (12%) knows what Lean Education is or teaches Lean in the classes (10%).
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BFBNIB, GIS, IJS, KISLJ, NUK, PNG, UL, UM, UPUK
Oil pollution caused by heavy shipping traffic in the Baltic Sea could be removed by the help of highly porous aerogels made from the waste. These could be produced from environmentally friendly ...cellulose, e.g., from paper waste, but would have to be hydrophobized for oil sorption. Such a cellulose aerogel was investigated in this research work. Six types of aerogel with 0.5, 1.0, 1.5, 2.0, 2.5 and 3.0 wt% cellulose with porosities in the range of 96–98% stabilized by unsaturated polyester as cross-linker have been produced. Aerogel’s sorption capacity as well as its regeneration for sorption of crude oil, marine diesel oil, and biodiesel sorption from water surface and mechanical strength has been estimated. It was found out that crude oil sorption capacity reach 29.67 ± 0.39 g g
−1
, biodiesel—29.07 ± 0.26 g g
−1
, while marine diesel oil—26.26 ± 0.39 g g
−1
. The aerogel with 0.5 wt% cellulose shows the best sorption properties after 10 cycles of the sorption.
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