Inhibitor of chromosomal DNA replication in xenopus: the turhuter protein

A composition is provided that inhibits DNA replication in activated cell-free extracts of Xenopus eggs, which is prepared by a process comprising subjecting homogenates of Xenopus ovaries to a series of chromatographic separations so as to isolate a purified fraction comprising a protein having a molecular weight ofabout 245 kDa

Bis{μ-1,3-bis­[(2-methyl-1H-benzimid­azol-1-yl)meth­yl]benzene-κ2 N 3:N 3′}bis­(diiodidocadmium)

In the title compound, [Cd2I4(C24H22N4)2], the 1,3-bis­[(2-methyl-1H-benzimidazol-1-yl)meth­yl]benzene ligand bridges two CdI2 units, forming a centrosymmetric dinuclear complex. The CdII atom adopts a distorted tetra­hedral coordination geometry. In the crystal, complex mol­ecules are linked into columns parallel to [101] by π–π stacking inter­actions, with centroid–centroid distances of 3.558 (2) Å

WHAT CAN TRANSLATION DO FOR THE ENDANGERED EARTH? – AN OVERVIEW OF ECOCRITICAL TRANSLATION STUDIES

Ecocritical translation studies aim to discover and interpret the human-nature relationship embodied and represented in translation. Different from studies on translation ecology, they focus on ecology related to nature, rather than using âecologyâ as a metaphor. This article attempts to clarify the ecocritical translation studies by analyzing their meaning, features, current studies and basic paradigms. Ecocriticism enables translation studies to transcend the human realm and delve into the natural world, challenging anthropocentrism. In the face of global eco-crises, it offers a new perspective and direction for translation studies, infusing these studies with a concern for nature, ecological values, and the responsibility to save the endangered earth

Synchrotron Mössbauer spectroscopic study of ferropericlase at high pressures and temperatures

The electronic spin state of Fe^(2+) in ferropericlase, (Mg_(0.75)Fe_(0.25))O, transitions from a high-spin (spin unpaired) to low-spin (spin paired) state within the Earth’s mid-lower mantle region. To better understand the local electronic environment of high-spin Fe^(2+) ions in ferropericlase near the transition, we obtained synchrotron Mössbauer spectra (SMS) of (Mg_(0.75),Fe_(0.25))O in externally heated and laser-heated diamond anvil cells at relevant high pressures and temperatures. Results show that the quadrupole splitting (QS) of the dominant high-spin Fe^(2+) site decreases with increasing temperature at static high pressure. The QS values at constant pressure are fitted to a temperature-dependent Boltzmann distribution model, which permits estimation of the crystal-field splitting energy (Δ_3) between the d_(xy_ and d_(xz) or d_(zy) orbitals of the t_(2g) states in a distorted octahedral Fe^(2+) site. The derived Δ_3 increases from approximately 36 meV at 1 GPa to 95 meV at 40 GPa, revealing that both high pressure and high temperature have significant effects on the 3d electronic shells of Fe^(2+) in ferropericlase. The SMS spectra collected from the laser-heated diamond cells within the time window of 146 ns also indicate that QS significantly decreases at very high temperatures. A larger splitting of the energy levels at high temperatures and pressures should broaden the spin crossover in ferropericlase because the degeneracy of energy levels is partially lifted. Our results provide information on the hyperfine parameters and crystal-field splitting energy of high-spin Fe^(2+) in ferropericlase at high pressures and temperatures, relevant to the electronic structure of iron in oxides in the deep lower mantle

Edge-Mediated Skyrmion Chain and Its Collective Dynamics in a Confined Geometry

The emergence of a topologically nontrivial vortex-like magnetic structure, the magnetic skyrmion, has launched new concepts for memory devices. There, extensive studies have theoretically demonstrated the ability to encode information bits by using a chain of skyrmions in one-dimensional nanostripes. Here, we report the first experimental observation of the skyrmion chain in FeGe nanostripes by using high resolution Lorentz transmission electron microscopy. Under an applied field normal to the nanostripes plane, we observe that the helical ground states with distorted edge spins would evolves into individual skyrmions, which assemble in the form of chain at low field and move collectively into the center of nanostripes at elevated field. Such skyrmion chain survives even as the width of nanostripe is much larger than the single skyrmion size. These discovery demonstrates new way of skyrmion formation through the edge effect, and might, in the long term, shed light on the applications.Comment: 7 pages, 3 figure

Suppression of the magnetic order in CeFeAsO: non-equivalence of hydrostatic and chemical pressure

We present a detailed investigation of the electronic properties of CeFeAsO under chemical (As by P substitution) and hydrostatic pressure by means of in-house and synchrotron M\"ossbauer spectroscopy. The Fe magnetism is suppressed due to both pressures and no magnetic order was observed above a P-substitution level of 40% or 5.2 GPa hydrostatic pressure. We compared both pressures and found that the isovalent As by P substitution change the crystallographic and electronic properties differently than hydrostatic pressure.Comment: supplement is included in the pdf fil

Thermodynamic insights into the intricate magnetic phase diagram of EuAl4_{4}

The tetragonal intermetallic compound EuAl$_{4}$ hosts an exciting variety of low temperature phases. In addition to a charge density wave below 140 K, four ordered magnetic phases are observed below 15.4 K. Recently, a skyrmion phase was proposed based on Hall effect measurements under a $c$-axis magnetic field. We present a detailed investigation of the phase transitions in EuAl$_{4}$ under $c$-axis magnetic field. Our dilatometry, heat capacity, DC magnetometry, AC magnetic susceptibility, and resonant ultrasound spectroscopy measurements reveal three magnetic phase transitions not previously reported. We discuss what our results reveal about the character of the magnetic phases. Our first key result is a detailed $H \parallel [001]$ magnetic phase diagram mapping the seven phases we observe. Second, we identify a new high-field phase, phase VII, which directly corresponds to the region were skyrmions have been suggested. Our results provide guidance for future studies exploring the complex magnetic interactions and spin structures in EuAl$_{4}$.Comment: 20 pages, 15 figure

Heme-protein vibrational couplings in cytochrome c provide a dynamic link that connects the heme-iron and the protein surface

The active site of cytochrome c (Cyt c) consists of a heme covalently linked to a pentapeptide segment (Cys-X-X-Cys-His), which provides a link between the heme and the protein surface, where the redox partners of Cyt c bind. To elucidate the vibrational properties of heme c, nuclear resonance vibrational spectroscopy (NRVS) measurements were performed on 57Fe-labeled ferric Hydrogenobacter thermophilus cytochrome c 552, including 13C8-heme-, 13C 515N-Met-, and 13C15N-polypeptide (pp)-labeled samples, revealing heme-based vibrational modes in the 200- to 450-cm-1 spectral region. Simulations of the NRVS spectra of H. thermophilus cytochrome c552 allowed for a complete assignment of the Fe vibrational spectrum of the protein-bound heme, as well as the quantitative determination of the amount of mixing between local heme vibrations and pp modes from the Cys-X-XCys-His motif. These results provide the basis to propose that heme-pp vibrational dynamic couplings play a role in electron transfer (ET) by coupling vibrations of the heme directly to vibrations of the pp at the protein - protein interface. This could allow for the direct transduction of the thermal (vibrational) energy from the protein surface to the heme that is released on protein/protein complex formation, or it could modulate the heme vibrations in the protein/protein complex to minimize reorganization energy. Both mechanisms lower energy barriers for ET. Notably, the conformation of the distal Met side chain is fine-tuned in the protein to localize heme-pp mixed vibrations within the 250-to 400-cm-1 spectral region. These findings point to a particular orientation of the distal Met that maximizes ET

Numerical simulation research on s-shaped elbows polished by abrasive flow based on large eddy simulation

To predict and improve the surface quality of complex curved surface structure precision machined by solid-liquid two-phase abrasive flow, this paper takes the S-shaped elbow as the research object, carries out the numerical simulation of abrasive flow polishing process of S-shaped elbow based on large eddy simulation method, analyzes the velocity distribution of abrasive flow, turbulent energy, wall shear force nephogram and trace diagram of abrasive flow in the S-shaped elbow under different inlet speed and abrasive concentration conditions. It is found that the values of velocity, turbulent energy and wall shear force on the inner side of the elbow and the outlet pipe are relatively large, indicating that the polishing quality at these positions is better. Increasing the inlet velocity can improve the effectiveness of abrasive flow polishing, and properly increasing the abrasive concentration can improve the surface uniformity of polished wall. It can provide a theoretical basis for promoting the continuous improvement of abrasive flow precision machining technology