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Die Politik der Frauen. Die Gründung des Frauenkomitees im Europäischen Gewerkschaftsbund Anfang der 1970er-Jahre
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Habitat selection and seed dispersal by the Great Blue Turaco (Corythaeola cristata) in the rainforests of southern Cameroon
No full textTransceiver 16-Channel Coaxial-End Dipole Array for Combined Head and C-Spine MRI at 9.4 T
No full textThis work aims to design a double-row transceiver array consisting of 16 folded-end coaxial-end dipoles for combined C-spine and brain imaging. The curved coaxial-end dipole elements were aligned on a tight-fitting, ergonomically shaped conformal holder optimized for subject comfort. Transmit efficiency, B1 + field homogeneity, and tissue-specific absorption rate (SAR) were numerically evaluated using electromagnetic simulations and optimized with respect to several configurations of the array geometry. After identifying the optimal array configuration, the array was built and tested on a bench and in the MRI scanner, using anatomical imaging and transmit field mapping on a phantom and healthy volunteers. The designed array provided RF excitation over the entire brain and cervical spinal cord down to the C7 region, covering a field of view of more than 365 mm in head-foot direction. Measured in a region covering the cerebrum, cerebellum, brainstem, and C-spine, it achieved B1 + field homogeneity of ~31% (coefficient of variation), mean transmit efficiency of ~0.38 μT/√W, and SAR efficiency of 0.65 μT/√W/kg when driven in the circularly polarized mode. The acquired anatomical MR images confirmed that the constructed array provided coverage of the brain and C-spine
Afar fossil shows broad distribution and versatility of Paranthropus (advance online)
No full textThe Afar depression in northeastern Ethiopia contains a rich palaeontological and archaeological record, which documents 6 million years of human evolution. Abundant faunal evidence links evolutionary patterns with palaeoenvironmental change as a principal underlying force1. Many of the earlier hominin taxa recognized today are found in the Afar, but Paranthropus has been conspicuously absent from the region. Here we report on the discovery, in the Mille-Logya research area, of a partial mandible that we attribute to Paranthropus, dated to between 2.5 and 2.9 million years ago and found in a well-understood chronological and faunal context. The find is among the oldest fossils attributable to Paranthropus and indicates that this genus, from its earliest known appearance, had a greater geographic distribution than previously documented2. Often seen as a dietary specialist feeding on tough food, the range of diverse habitats with which eastern African Paranthropus can now be associated shows that this suggested adaptive niche did not restrict its ability to disperse as widely as species of Australopithecus and early Homo. The discovery of Paranthropus in the Afar emphasizes how little is known about hominin evolution in eastern Africa during the crucial period between 3 and 2.5 million years ago, when this genus and the Homo lineage presumably emerged
Germline fate determination by a single ARGONAUTE protein in Ectocarpus
No full textARGONAUTE (AGO) proteins are a highly conserved family of RNA-binding proteins that play central roles in gene regulation and developmental processes across eukaryotes. Although AGO family members have been extensively studied in animals and plants, where they are typically encoded by multiple genes, their function in brown algae, a diverse and complex group of multicellular algae, remains largely unknown. Here, we show that the genomes of several brown algae encode only a single AGO protein, containing the conserved functional domains characteristic of the family. Using the model brown alga Ectocarpus and a combination of cell biology, genetic, and transcriptomic approaches, we demonstrate that AGO is essential for the transition from vegetative growth to sexual reproductive development and for germline establishment. Our results further suggest that AGO functions in concert with microRNAs to regulate target genes primarily at the posttranscriptional level, likely through translational repression. Ectocarpus thus represents a rare example of a complex multicellular organism that relies on a single AGO protein to regulate key developmental processes, pointing to a minimalistic model of RNA-based regulation in brown algae
Bandwidth-tuned Mott transition and superconductivity in moiré WSe<sub>2</sub>
No full textThe emergence of high-transition-temperature (Tc) superconductivity in strongly correlated materials remains the main unsolved problem in physics. High-Tc materials, such as cuprates, are generally complex and not easily tunable, making theoretical modelling difficult. Although the Hubbard model—a simple theoretical model of interacting electrons on a lattice—is believed to capture the essential physics of high-Tc materials1,2,3,4,5, obtaining accurate solutions of the model, especially in the relevant regime of moderate correlation, is challenging6. The recent demonstration of robust superconductivity in moiré WSe2 (refs. 7,8), in which low-energy electronic bands can be described by the Hubbard model and are highly tunable9,10,11, presents a new platform for studying the high-Tc problem. Here we tune moiré WSe2 bilayers to the moderate correlation regime through the twist angle and map the phase diagram around one hole per moiré unit cell (ν = 1) by electrostatic gating and electrical transport and magneto-optical measurements. We observe a range of high-Tc phenomenology, including an antiferromagnetic insulator at ν = 1, superconducting domes on electron and hole doping, and unusual metallic states such as strange metals12,13,14. Twist-angle dependence studies further show that the highest Tc always occurs adjacent to the Mott transition3,15. Our results indicate strong correlation as the key to superconductivity in moiré WSe2 and establish a new material system for studying high-Tc superconductivity in a controllable manner
Neural and psychophysiological correlates of cognitive, social, and emotional development of infants and children of mothers with peripartum depression: A systematic review
No full textIf left untreated, peripartum depression (PPD) can significantly disrupt mother-infant interactions and is associated with long-term negative consequences for child development. The aim of this article was to systematically review studies examining the underlying neural and physiological markers associated with socioemotional and cognitive development in infants and children exposed to maternal PPD. A literature search was conducted in PubMed, MEDLINE, PsycINFO, Web of Science, Scopus, Embase, and Cochrane databases, covering studies from their inception until July 2024. Six studies were included in this review. Two studies assessed PPD symptoms during pregnancy, two during the postpartum period, and two during both pregnancy and the postpartum period. The findings suggest that the developmental outcomes of the offspring of depressed mothers during the perinatal period may be underpinned by specific correlates of brain activity and psychophysiological functioning-specifically, greater right frontal EEG asymmetry, heightened activation of the amygdala and other paralimbic structures, lower vagal tone, and increased N2 latencies. This review highlights the need for further research in this area