The structural and magnetic properties of seven CeMn2Ge(2-x)Six compounds with x = 0.0-2.0 have been investigated in detail. Substitution of Ge with Si leads to a monotonic decrease of both a and c along with concomitant contraction of the unit cell volume and significant modifications of the magnetic states - a crossover from ferromagnetism at room temperature for Ge-rich compounds to antiferromagnetism for Si-rich compounds. The magnetic phase diagram has been constructed over the full range of CeMn2Ge(2-x)Six compositions and co-existence of ferromagnetism and antiferromagnetism has been observed in CeMn2Ge1.2Si0.8, CeMn2Ge1.0Si1.0 and CeMn2Ge0.8Si1.2 with novel insight provided by high resolution neutron and X-ray synchrotron radiation studies. CeMn2Ge(2-x)Six compounds (x = 0, 0.4 and 0.8) exhibit moderate isothermal magnetic entropy accompanied with a second-order phase transition around room temperature. Analysis of critical behaviour in the vicinity of TC(inter) for CeMn2Ge2 compound indicates behaviour consistent with three-dimensional Heisenberg model predictions.
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http://dx.doi.org/10.1038/srep11288 | DOI Listing |
Proc Natl Acad Sci U S A
January 2025
Laboratory of Crystallographic Studies, Instituto Andaluz de Ciencias de la Tierra, Consejo Superior de Investigaciones Científica, Armilla 18100, Spain.
Revealing the origin of life and unambiguously detecting fossil remains of the earliest organisms are closely related aspects of the same scientific research. The synthesis of prebiotic molecular building blocks of life and the first compartmentalization into protocells have been considered two events apart in time, space, or both. We conducted lightning experiments in borosilicate reactors filled with a mixture of gases mimicking plausible geochemical conditions of early Earth.
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January 2025
Zhejiang Key Laboratory of Biology and Ecological Regulation of Crop Pathogens and Insects, Institute of Insect Sciences, Zhejiang University, Hangzhou, Zhejiang 310058, China.
The harlequin ladybird, , is a predatory beetle used globally to control pests such as aphids and scale insects. Originating from East Asia, this species has become highly invasive since its introduction in the late 19th century to Europe and North America, posing a threat to local biodiversity. Intraguild predation is hypothesized to drive the success of this invasive species, but the underlying mechanisms remain unknown.
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January 2025
Department of Cell & Developmental Biology, School of Biological Sciences, University of California San Diego, La Jolla, CA 92093.
A spectacular diversity of forms and features allow species to thrive in different environments, yet some structures remain relatively unchanged. Insect compound eyes are easily recognizable despite dramatic differences in visual abilities across species. It is unknown whether distant insect species use similar or different mechanisms to pattern their eyes or what types of genetic changes produce diversity of form and function.
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January 2025
School of Biomolecular Science and Engineering, Vidyasirimedhi Institute of Science and Technology (VISTEC), Rayong 10120, Thailand.
A single-component flavin-dependent halogenase, AetF, has emerged as an attractive biocatalyst for catalyzing halogenation. However, its flavin chemistry remains unexplored and cannot be predicted due to its uniqueness in sequence and structure compared to other flavin-dependent monooxygenases. Here, we investigated the flavin reactions of AetF using transient kinetics.
View Article and Find Full Text PDFACS Chem Neurosci
January 2025
Department of Bioengineering and Biotechnology, Birla Institute of Technology Mesra, Ranchi, Jharkhand 835215, India.
Alzheimer's disease (AD) is a progressive neurodegenerative disorder characterized by cognitive decline, extracellular amyloid-β (Aβ) plaque accumulation, and intracellular neurofibrillary tangles. Recent efforts to find effective therapies have increased interest in natural compounds with multifaceted effects on AD pathology. This study explores natural compounds for their potential to mitigate AD pathology using molecular docking, ADME screening, and assays, with ruscogenin─a steroidal sapogenin from emerging as a promising candidate.
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