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Density functional theory in the local spin density approximation is used to investigate the structural, electronic, and magnetic properties of PbRuO3 under hydrostatic pressure. The calculated results show that under hydrostatic pressure, the ground state of Pm 3 ¯ m PbRuO3 is a ferromagnetic metal. The covalent bond of Pb–O strengthens as hydrostatic pressure increases, the exchange splitting of up- and down-spin channels of Ru 4d t2g weakens, and the magnetic properties decrease. The calculated ground state of Pbnm PbRuO3 is a paramagnetic metal, which is consistent with the experimental results at P = 0 GPa. The ground state of Imma PbRuO3 has weak ferromagnetism, which is close to the experimental results at P = 0 GPa. The Pbnm–Imma phase transition occurs when passing the critical hydrostatic pressure. The main reason is the distortion of Pb2+ at the A-site, which changed the bond length of Pb–O and the covalent strength of Pb–O, affecting the electron occupation of Ru 4d and leading to the Pbnm–Imma phase transition. [ABSTRACT FROM AUTHOR]

Using the density functional theory with the plane‐wave ultrasoft pseudopotentials method within the local density approximation (LDA), the magnetic structure of CaRuO3 (hereafter referred to as CRO) is studied as a function of hydrostatic pressure. The calculated results show that: 1) the compressive stress does not cause the disappearance of the ferromagnetic (FM) ground state of cubic CRO but only reduces the magnetic ordering energy and magnetic moment per formula unit, and that 2) the orthorhombic CRO with the Pbnm structure is just in the critical region of the FM, antiferromagnetic (AF), and paramagnetic ground states. Although there is no evidence of an AF phase of CRO at low temperature, the calculated results show that an AF interaction does exist between the Ru atoms of CRO. This can explain the negative Weiss temperature of CRO and the abnormal behavior of the magnetic susceptibility of CRO at low temperature. The AF interaction and the sensitivity to the crystal structure may be the reasons for the various properties of CRO. [ABSTRACT FROM AUTHOR]

Using the density functional theory with the plane‐wave ultrasoft pseudopotentials method within the local density approximation (LDA), the magnetic structure of CaRuO3 (hereafter referred to as CRO) is studied as a function of hydrostatic pressure. The calculated results show that: 1) the compressive stress does not cause the disappearance of the ferromagnetic (FM) ground state of cubic CRO but only reduces the magnetic ordering energy and magnetic moment per formula unit, and that 2) the orthorhombic CRO with the Pbnm structure is just in the critical region of the FM, antiferromagnetic (AF), and paramagnetic ground states. Although there is no evidence of an AF phase of CRO at low temperature, the calculated results show that an AF interaction does exist between the Ru atoms of CRO. This can explain the negative Weiss temperature of CRO and the abnormal behavior of the magnetic susceptibility of CRO at low temperature. The AF interaction and the sensitivity to the crystal structure may be the reasons for the various properties of CRO. [ABSTRACT FROM AUTHOR]

The structure, electronic and magnetic properties of SrRuO 3 and PbRuO 3 are studied by using density functional theory in the local spin density approximation. The lattice constants of orthorhombic SrRuO 3 and PbRuO 3 with a Pbnm space group have a > b, different from most of other ABO 3 structures with a < b. We obtain two reasons about a > b for SrRuO 3 and PbRuO 3 : One is that the horizontal middle plane of the oxygen octahedra deforms from square to rectangle, resulting in the side length of rectangle along x direction, a oct , is larger than that along y direction, b oct ; The other is the tilting angle of the oxygen octahedra having θ < arccos (b oct /a oct). SrRuO 3 and PbRuO 3 with similar structure should have similar magnetic ground states. But SrRuO 3 is ferromagnetic, while PbRuO 3 is paramagnetic. Our results show that the orbital hybridization of Pb–O is much stronger than that of Sr–O, which lead to the broaden bandwidth near Fermi level. This is the main reason for the different magnetic ground states of SrRuO 3 and PbRuO 3. The calculations for PbRuO 3 with Pbnm and Imma structures have considered the spin-orbit coupling effect, the calculated results show that the ground states of Pbnm and Imma PbRuO 3 are both paramagnetic metals. The rectangle deformation of the horizontal base plane of the oxygen octahedra and the tilting angle of the oxygen octahedra determine the relationship of lattice constants a and b jointly. The strength of A-O covalence, the rotation (tilting) angles and rectangle deformation of the oxygen octahedra can regulate the magnetic properties of SrRuO 3 and PbRuO 3. [Display omitted] • The lattice constants of Pbnm SrRuO 3 (PbRuO 3) match a> b, we obtain the reasons. • Due to strong Pb-O hybridization, the broaden bandwidth near Fermi level resulting in the paramagnetic ground state for PRO. • The deformations of the oxygen octahedra have a great effect on the magnetic properties of SrRuO 3 and PbRuO 3. [ABSTRACT FROM AUTHOR]

Variation in the condition of marine sediments provides selective preservation milieus, which act as a key determinant for the abundance and distribution of dinoflagellate resting cysts in natural sediments. Microbial degradation is an understudied biological factor of potential importance in the processes. However, gaps remain in our knowledge about the fundamental information of the bacterial consortia associated with dinoflagellate resting cysts both in laboratory cultures and in the field. Here we used Scrippsiella acuminata as a representative of cyst-producing dinoflagellates to delineate the diversity and composition of bacterial microbiomes co-existing with the laboratory-cultured resting cysts, and to explore possible impacts of low temperature, darkness, and anoxia (the mock conditions commonly observed in marine sediments) on the associated bacterial consortia. Bacterial microbiome with high diversity were revealed associated with S. acuminata at resting stage. The mock conditions could significantly shift bacterial community structure and exert notably inhibitory effects on growth-promoting bacteria. Resting cysts under conditions typically observed in marine sediments fostered bacterial microbiomes with more diverse trophic strategies, characteristic of prominently enriched anaerobic chemotrophic bacteria generating energy via respiration with several different terminal electron acceptors, which yielded more acidic milieu unfavorable for the preservation of calcareous resting cysts. Our findings suggest that there is complex and dynamic interaction between dinoflagellates resting cysts and the associated bacterial consortia in natural sediments. This intrinsic interaction may influence the maintenance and/or accumulation of dinoflagellate resting cysts with potential of germination and initiation blooms in the field., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest. The author(s) declared that they were an editorial board member of Frontiers, at the time of submission. This had no impact on the peer review process and the final decision., (Copyright © 2024 Deng, Li, Shang, Hu, Yue and Tang.)

This study attempted to investigate the effect of impregnation sequence of the Pd/Ce/γ-Al 2 O 3 sorbents on Hg 0 removal. To this end, five kinds of sorbents were prepared and tested in simulated coal derived fuel gas (N 2 -H 2 -CO-H 2 S-Hg), including Pd/γ-Al 2 O 3 , Ce/γ-Al 2 O 3 and three kinds of Pd-based sorbents with Ce impregnation on γ-Al 2 O 3 substrate. The tests were conducted at 250 and 300 °C respectively. According to the results, bimetallic Ce-Pd/γ-Al 2 O 3 sorbent prepared by simultaneously impregnating Pd and Ce showed much higher and more stable removal efficiency of Hg 0 than the other three kinds of sorbents. The Hg 0 removal efficiency of Ce-Pd/γ-Al 2 O 3 sorbent reached above 98% within 480 min at 250 °C and 91% within 200 min at 300 °C. Characterization results indicated that the sorbent Ce-Pd/γ-Al 2 O 3 prepared by the co-impregnation method had bigger specific surface area (216.6 m 2 /g) than the other three kinds of Pd-based sorbents. The content Pd and Ce on the sorbent Ce-Pd/γ-Al 2 O 3 surface is 0.21% and 0.61%, which proved higher than that of the other three kinds of Pd-based sorbents, and observation from STEM-XEDS maps showed it demonstrated the highest dispersion. It is found that Ce is likely to promote the dispersion of Pd on the support surface during the preparation of the sorbent under the co-impregnation method. Meanwhile, Ce enhanced the H 2 S resistance of the sorbent. Thereby, Ce-Pd/γ-Al 2 O 3 sorbent is found to have the optimal performance of mercury removal. In this study, the Hg 0 removal mechanism of the Pd/Ce/γ-Al 2 O 3 sorbents in the simulated coal derived fuel gas was also elaborated., Competing Interests: Declaration of interest statement This manuscript is approved by all authors for publication. We certify that this manuscript, or any part of it, has not been published and submitted elsewhere for publication while being considered by your journal., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

The development of targeted nanoprobes is a promising approach to cancer diagnostics and therapy. In the present work, a novel multifunctional photo/magnet-diagnostic nanoprobe (MNPs-PEG 2K -FA@Ce6) has been developed. This nanoprobe is built using folic acid (FA), bifunctional polyethylene glycol (PEG 2K ) and photosensitizer chlorin e6 (Ce6). The MNPs-PEG 2K -FA@Ce6 nanoprobes are superparamagnetic, can be synthesized on a large scale by a one-pot hydrothermal process without further surface modification and are stable in an aqueous environment for eight months. Compared with free Ce6 nanoprobes in vitro studies, the MNPs-PEG 2K -FA@Ce6 nanoprobes significantly enhance cellular uptake efficiency and promote the effectiveness of photodynamic therapy (PDT) with the assistance of 633 nm laser irradiation. The unique nanoprobes show superior penetration and a retention time of more than six days with less accumulation in the liver allowing highly effective tumor recognition and monitoring. Additionally, there was little damage to healthy organs or tissues. These exciting new nanoprobes could be potential building blocks to develop new clinical therapies and translational medicine.

Objective: To study the morphological characteristics and immunophenotype of highly cellular leiomyoma (HCL) of uterus, compared with that of uterine endometrial stromal tumors (EST)., Methods: HE and immuno-stained sections EnVision method from 20 cases of HCL, 21 cases of EST and 1 case of stromomyoma were reviewed. Monoclonal antibodies against h-caldesmon, calponin, CD10, desmin and smooth muscle actin (SMA) were used for immunohistochemistry studies., Results: On microscopic examination, HCL were densely cellular and composed of cells that ranged from spindle-shaped to round with scanty cytoplasm. A focal fascicular pattern was present in all cases. Blood vessels with large, thick muscular walls were a conspicuous feature of the majority of tumors. Cleft-like spaces were present in 9 tumors and 15 cases exhibited irregular focal extensions into the adjacent myometrium. ESTs were composed of cells that resembled endometrial stromal cells of proliferative endometrium. These cases included a significant component of delicate blood vessels similar to spiral arterioles. All 20 low grade endometrial stromal sarcoma cases had infiltrative growth to adjacent myometrium. Immunoreactivities of HCL for h-caldesmon, calponin, CD10, Desmin and SMA were 80.0% (16/20), 100% (20/20), 0 (0/20), 95.0% (19/20) and 100% (20/20), respectively, whereas the positive rates of EST were 4.7% (1/21), 23.8% (5/21), 66.7% (14/21), 23.8% (5/21) and 19.0% (4/21), respectively (P = 0.001)., Conclusions: Highly cellular leiomyomas have distinct morphologic features. H-caldesmon, calponin, CD10, desmin and SMA are helpful in the differential diagnosis of HCL and EST.