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C17H14N2S, Orthorhombic, P212121 (no. 19), a = 5.9687(10) Å, b = 8.4626(14) Å, c = 28.786(5) Å, V = 1454.0(4) Å3, Z = 4, R gt(F) = 0.0315, wR ref(F 2) = 0.0824, T = 296(2) K.

C17H16OS, monoclinic, P21/n (no. 14), a = 5.4605(12) Å, b = 19.767(4) Å, c = 13.357(4) Å, β = 92.834(3)°, V = 1,439.9(6) Å3, Z = 4, R gt(F) = 0.0398, wR ref(F 2) = 0.1144, T = 296(2) K.

This study was conducted to illustrate the origin of these PE-related ncRNAs in maternal circulation and their underlying transport methods into target cells. We selected 10 women with severe pre-eclampsia (PE group) and 10 healthy participants who served as controls (NC group). Exosomes were isolated from their sera and their origin was determined by a specific marker, placental alkaline phosphatase (PLAP). We compared the ncrna associated with PE in exosomes and whole serum to observe the exchange of serum exosomes with trophoblast cells. The results showed that PLAP was enriched in the isolated exosomes. Seven PE-associated ncRNAs, including lnc-SNHG5, miR-26a-5p, miR-221-3p, miR-30a-3p, miR-18a, miR-152 and miR-155, were analyzed in placenta-derived exosomes and whole serum from both groups. miR-26a-5p, miR-152 and miR-155 were upregulated in the PE group compared with the NC group. 152 and miR-155 were upregulated. 152 and miR-155 were upregulated, while miR-18a and miR-221-3p were downregulated (P<0.05). ncRNAs were altered in serum and placenta-derived serum exosomes in a consistent trend. Fluorescence microscopy results showed that the nuclei were counterstained in HTR-8 cells exposed to PKH26-labeled exosomes. PE-associated ncRNAs can enter the maternal circulation through secretion and encapsulation into placenta-derived exosomes and participate in the development and progression of PE by targeting trophoblast cells. differential expression of ncRNAs in exosomes has the potential to be used as predictors for targeted therapy, providing new ideas and perspectives for improving maternal and infant outcomes. [ABSTRACT FROM AUTHOR]

Endo-norbornene derivatives are much cheaper and more accessible. However, it is difficult to prepare endo-polynorbornenes with ultra-high molecular weight (UHMW) by ring opening metathesis polymerization (ROMP) owing to the low activity. The molecular weight of poly(endo-NB-2OH)n could only reach to 309.1 kg mol−1 for 24 h via ROMP. While, UHMW poly(endo-NB-2OH)m was prepared by combining ROMP and acyclic metathesis reaction in much shorter time. The effects of residual monomer, amount of H2SO4, concentration, temperature and reaction time were investigated in depth. The UHMW P(endo-NB-2OH)m (Mn=2645.5 kg mol−1, PDI = 1.74) could be obtained at 80 °C for 5 min with H2SO4/G3 as 10/1 and concentration of 0.1 M. Moreover, UHMW P(endo-NBI-OH)m(Mn=1114.2 kg mol−1, PDI = 1.95) was also successfully prepared by this method. However, the H2SO4/G3 should increase to 30/1, and reacted for 45 min owing to the steric resistance of the cyclic dicarboximide. For P(exo-NBI-OH)n with lower activity, reaction time should prolong to 3 h to obtain UHMW P(exo-NBI-OH)m(Mn=1716.7 kg mol−1, PDI = 1.93). Finally, UHMW P(endo-NB-2alkyne)m, P(endo-NBI-alkyne)m, and P(exo-NBI-alkyne)m were successfully prepared via post-modification. Acyclic metathesis reaction is a robust and universal reaction to prepare other functional UHMW polynorbornenes, especially for the UHMW endo-polynorbornenes, which could not be prepared by ROMP efficiently. [ABSTRACT FROM AUTHOR]

This document is a discussion of various research papers on different topics. The first paper explores the influence of downstream channel width on flow features in a T-shaped open-channel confluence. The authors conducted numerical simulations to study flow characteristics such as stagnation zone location, tributary inflow angles, separation zone dimensions, flow acceleration, secondary flow patterns, and bed shear stresses. The second paper focuses on the backwater effect in a T-shaped junction channel, examining the impact of junction angle, width ratio, discharge ratio, and bed level discordance. The third paper discusses the backwater effect in river channels caused by variations in bed level and width ratios, finding that increasing discharge upstream and enlarging the downstream width of the main channel can mitigate the backwater effect. The final report analyzes the properties of the star system GJJ211936, including its spectral type, luminosity, and distance from Earth. It also examines the potential habitability of the system's exoplanets and emphasizes the importance of further research in the search for extraterrestrial life. [Extracted from the article]

The interface between soil and concrete in cold climates has a significant effect on the structural integrity of embedded structures, including piles, liners, and others. In this study, a novel temperature control system was employed to conduct direct shear tests on this interface. The test conditions included normal stress (25 to 100 kPa), temperature (ranging from 20 to −6 °C), water content (from 10 to 19%), and shear rates (0.1 to 1.2 mm/min). Simultaneously, the deformation process of the interface was continuously photographed using a modified visual shear box, and the non-uniform deformation mechanism of the interface was analyzed by combining digital image correlation (DIC) technology with the photographic data. The findings revealed that the shear stress–shear displacement curves did not exhibit a discernible peak strength at elevated temperatures, indicating deformation behavior characterized by strain hardening. In the frozen state, however, the deformation softened, and the interfacial ice bonding strength exhibited a positive correlation with decreasing temperature. When the initial water content was 16% and the normal stress was 100 kPa, the peak shear strength increased significantly from 99.9 kPa to 182.9 kPa as the test temperature dropped from 20 °C to −6 °C. Both shear rate and temperature were found to have a marked effect on the peak shear strength, with interface cohesion being the principal factor contributing to this phenomenon. At a shear rate of 0.1 mm/min, the curve showed hardening characteristics, but at other shear rates, the curves exhibited strain-softening behavior, with the softening becoming more pronounced as shear rates increased and temperatures decreased. Due to the refreezing of interfacial ice, the residual shear strength increased in proportion to the reduction in shear rate. On a mesoscopic level, it was evident that the displacement of soil particles near the interface exhibited more pronounced changes. At lower shear rates, the phenomenon of interfacial refreezing became apparent, as evidenced by the periodic changes in interfacial granular displacement at the interface. [ABSTRACT FROM AUTHOR]

Iron-based anode materials usually exhibit an unsatisfactory rate performance and poor cycle stability during Li+ storage. Herein, ultrathin hexagonal Fe3O4 nanosheets are embedded in nitrogen-doped carbon nanofibers (hexa-Fe3O4@N-CNF), boosting the Li+ diffusion kinetics and maintaining cycling stability. The ultrathin hexa-Fe3O4 nanosheets possess a short Li+ diffusion pathway, while N-CNF displays excellent conductivity, both of which contribute to the rapid insertion/extraction of Li+. The iron-induced thermal-catalyzed N-CNF manifests enhanced mechanical stability due to its increased graphitization degree, which effectively alleviates the mechanical stress resulting from the volume change of the hexa-Fe3O4 during Li+ storage, thereby enhancing the cyclic stability of hexa-Fe3O4@N-CNF. The compressed anode of hexa-Fe3O4@N-CNF presents a high mass loading (3.3 mg cm–2) and is coupled with a flexible cathode (activated carbon casted onto N-CNF) to assemble the quasi-solid-state lithium-ion hybrid capacitor (LIHC), enabling the attainment of high volumetric power/energy density (66.5 W h L–1 at 117.9 W L–1 and 38.5 W h L–1 at 11785.7 W L–1). When the LIHC is bent at 180°, its Li+ storage performance illustrates a negligible degradation. Additionally, LIHC features a low self-discharge rate (∼14.2 mV h–1). Overall, the long-term cycle stability, high power/energy density, low self-discharge rate, as well as mechanical robustness render this LIHC a suitable candidate for flexible energy storage applications. [ABSTRACT FROM AUTHOR]

This paper investigates integrable decompositions of the (2 + 1)-dimensional multi-component Ablowitz-Kaup-Newell-Segur (AKNS in brief) hierarchy. By utilizing recursive relations and symmetric reductions, it is demonstrated that the (n2 − n1 + 1)-flow of the (2 + 1)-dimensional coupled multi-component AKNS hierarchy can be decomposed into the corresponding n1-flow and n2-flow of the coupled multi-component AKNS hierarchy. Specifically, except for two specific scenarios, the (n2 − n1 + 1)-flow of the (2 + 1)-dimensional reduced multi-component AKNS hierarchy can similarly be decomposed into the corresponding n1-flow and n2-flow of the reduced multi-component AKNS hierarchy. Through the application of these integrable decompositions and Darboux transformation techniques, multiple solitons for the standard focusing multi-component "breaking soliton" equations, as well as singular, exponential, and rational solitons for the nonlocal defocusing multi-component "breaking soliton" equations, are systematically presented. Furthermore, the elastic interactions and dynamical behaviors among these soliton solutions are thoroughly investigated without loss of generality. [ABSTRACT FROM AUTHOR]

Two enantiomeric pairs of new 3d–4f heterometallic clusters have been synthesized from two enantiomer Schiff base derivatives: (R/S)-2-[(2-hydroxy-1-phenylethylimino)methyl] phenol (R-/S-H2L). The formulae of the series clusters are Co3Ln(R-L)6 (Ln = Dy (1R), Gd (2R)), Co3Ln (S-L)6 (Ln = Dy (1S), Gd (2S)), whose crystal structures and magnetic properties have been characterized. Structural analysis indicated that the above clusters crystallize in the chiral P213 group space. The central lanthanide ion has a coordination geometry of D3 surrounded by three [CoIII(L)2]– anions using six aliphatic oxygen atoms of L2− featuring a star-shaped [CoIII3LnIII] configuration. Magnetic measurements showed the presence of slow magnetic relaxation with an effective energy barrier of 22.33 K in the DyIII derivatives under a zero-dc field. Furthermore, the circular dichroism (CD) spectra of 1R and 1S confirmed their enantiomeric nature. [ABSTRACT FROM AUTHOR]

Ring opening metathesis polymerization (ROMP) is widely used to prepare functional materials with various topological structures. However, it is difficult to prepare polymers with ultra‐high molecular weight (UHMW) directly. We found a new method to prepare UHMW polymers by combining ROMP and acyclic metathesis reaction. First, monomer NB‐2OH was polymerized by ROMP with different feed ratio of NB‐2OH/G3, and obtained well‐defined polymers P(NB‐2OH)n (n = 50, 200, and 463). Then acyclic metathesis reaction was used to synthesize UHMW polymers. The results indicated that polymer P(NB‐2OH)z with higher molecular weight (Mw = 6067.3 kg mol−1) and narrower distribution (PDI = 1.58) could be obtained at 80°C for 5 min, when P(NB‐2OH)463 was used as raw material with H2SO4/G3 = 10/1. Compared with polymer P(NB‐2OH)1990 (Mw = 5343.1 kg mol−1, PDI = 1.61) prepared by ROMP directly, the new method tremendously shortens reaction time, lowers the requirement for the purity of monomer and produces UHMW polymers with narrower distribution. The compositions of prepared polymers were also confirmed clearly by post‐modification and 1H NMR characterization. [ABSTRACT FROM AUTHOR]