The absence of inversion symmetry in non-centrosymmetric materials has a fundamental role in the emergence of a vast number of fascinating phenomena, like ferroelectricity, second harmonic ...generation, and Weyl fermions. The removal of time-reversal symmetry in such systems further extends the variety of observable magneto-electric and topological effects. Here we report the striking topological properties in the non-centrosymmetric spin-orbit magnet PrAlGe by combining spectroscopy and transport measurements. By photoemission spectroscopy below the Curie temperature, we observe topological Fermi arcs that correspond to projected topological charges of ±1 in the surface Brillouin zone. In the bulk, we observe the linear energy-dispersion of the Weyl fermions. We further observe a large anomalous Hall response in our magneto-transport measurements, which is understood to arise from diverging bulk Berry curvature fields associated with the Weyl band structure. These results establish a novel Weyl semimetal phase in magnetic non-centrosymmetric PrAlGe.
Deep eutectic solvents (DESs) are a class of promising media for gas separation. In order to examine the potential application of DESs for natural gas upgrading, the solubilities of H2S, CO2, and CH4 ...in choline chloride (ChCl) plus urea mixtures were measured in this work. The solubility data were correlated with Henry's law equation to calculate the thermodynamic properties of gas absorption processes, such as Henry's constants and enthalpy changes. Grand‐canonical Monte Carlo simulations and quantum chemistry calculations were also performed to examine the mechanism of gas absorption processes. It is found that the absorption of H2S in ChCl + urea mixtures is governed by the hydrogen‐bond interaction between Cl of ChCl and H of H2S, whereas the absorption of CO2 and CH4 in ChCl+urea mixtures is governed by the free volume of solvents. Based on the different behavior of gas absorption, high H2S/CO2, H2S/CH4, and CO2/CH4 selectivities can be achieved by adjusting the ratio of ChCl/urea in mixtures.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
Mammalian pre-implantation development is a complex process involving dramatic changes in the transcriptional architecture. We report here a comprehensive analysis of transcriptome dynamics from ...oocyte to morula in both human and mouse embryos, using single-cell RNA sequencing. Based on single-nucleotide variants in human blastomere messenger RNAs and paternal-specific single-nucleotide polymorphisms, we identify novel stage-specific monoallelic expression patterns for a significant portion of polymorphic gene transcripts (25 to 53%). By weighted gene co-expression network analysis, we find that each developmental stage can be delineated concisely by a small number of functional modules of co-expressed genes. This result indicates a sequential order of transcriptional changes in pathways of cell cycle, gene regulation, translation and metabolism, acting in a step-wise fashion from cleavage to morula. Cross-species comparisons with mouse pre-implantation embryos reveal that the majority of human stage-specific modules (7 out of 9) are notably preserved, but developmental specificity and timing differ between human and mouse. Furthermore, we identify conserved key members (or hub genes) of the human and mouse networks. These genes represent novel candidates that are likely to be key in driving mammalian pre-implantation development. Together, the results provide a valuable resource to dissect gene regulatory mechanisms underlying progressive development of early mammalian embryos.
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DOBA, IJS, IZUM, KILJ, KISLJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
The intrinsic conflicts between mechanical performances and processability are main challenges to develop cost‐effective impact‐resistant materials from polymers and their composites. Herein, ...polyhedral oligomeric silsesquioxanes (POSSs) are integrated as side chains to the polymer backbones. The one‐dimension (1D) rigid topology imposes strong space confinements to realize synergistic interactions among POSS units, reinforcing the correlations among polymer chains. The afforded composites demonstrate unprecedented mechanical properties with ultra‐stretchability, high rate‐dependent strength, superior impact‐resistant capacity as well as feasible processability/recoverability. The hierarchical structures of the hybrid polymers enable the co‐existence of multiple dynamic relaxations that are responsible for fast energy dissipation and high mechanical strengths. The effective synergistic correlation strategy paves a new pathway for the design of advanced cluster‐based materials.
Unique physical interaction facilitated by 1D topologies of molecular cluster‐integrated polymers is applied for the design of impact‐resistant materials with exceptional energy dissipation capability and strong rate‐dependent mechanical strengths, enabling the simultaneous achievement of promising impact resistance and processability/recoverability.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
Granular materials, composed of densely packed particles, are known to possess unique mechanical properties that are highly dependent on the surface structure of the particles. A microscopic ...understanding of the structure‐property relationship in these systems remains unclear. Here, supra‐nanoparticle clusters (SNPCs) with precise structures are developed as model systems to elucidate the unexpected elastic behaviors. SNPCs are prepared by coordination‐driven assembly of polyhedral oligomeric silsesquioxane (POSS) with metal‐organic polyhedron (MOP). Due to the disparity in sizes, the POSS‐MOP assemblies, like their classic nanoparticles counterparts, ordering is suppressed, and the POSS‐MOP mixtures will vitrify or jam as a function of decreasing temperature. An unexpected elasticity is observed for the SNPC assemblies with a high modulus that is maintained at temperatures far beyond the glass transition temperature. From studies on the dynamics of the hierarchical structures of SNPCs and molecular dynamic simulation, the elasticity has its origins in the interpenetration of POSS‐ended arms. The physical molecular interpenetration and inter‐locking phenomenon favors the convenient solution or pressing processing of the novel cluster‐based elastomers.
Supra‐nanoparticle clusters (SNPCs) were synthesized by convergence of metal–organic polyhedron scaffolds with precise giant building blocks. The mechanical properties and structural dynamics can be regulated by fine‐tuning the surface functionalization of the terminal POSS moieties. Unexpected elasticity with high Young's modulus of the OPOSS‐ended SNPCs was found to be highly correlated with the interpenetration of the neighboring GLs.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
The binding strength of reactive intermediates with catalytically active sites plays a crucial role in governing catalytic performance of electrocatalysts. NiFe hydroxide offers efficient oxygen ...evolution reaction (OER) catalysis in alkaline electrolyte, however weak binding of oxygenated intermediates on NiFe hydroxide still badly limits its catalytic activity. Now, a facile ball‐milling method was developed to enhance binding strength of NiFe hydroxide to oxygenated intermediates via generating tensile strain, which reduced the anti‐bonding filling states in the d orbital and thus facilitated oxygenated intermediates adsorption. The NiFe hydroxide with tensile strain increasing after ball‐milling exhibits an OER onset potential as low as 1.44 V (vs. reversible hydrogen electrode) and requires only a 270 mV overpotential to reach a water oxidation current density of 10 mA cm−2.
NiFe hydroxide was treated by ball‐milling to enhance its binding strength to an oxygenated intermediate. The prepared NiFe hydroxide that has induced tension shows excellent oxygen evolution performance.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
New chiral targets of orientational chirality have been designed and asymmetrically synthesized by taking advantage of N‐sulfinyl imine‐directed nucleophilic addition/oxidation, Suzuki‐Miyaura, and ...Sonogashira cross‐coupling reactions. Orientation of single isomers has been selectively controlled by using aryl/alkynyl levers C(sp2)‐C(sp) axis and tBuSO2‐ protecting group on nitrogen as proven by X‐ray diffraction analysis. The key structural characteristic of resulting orientational products is shown by remote through‐space blocking manner. Seventeen examples of multi‐step synthesis were obtained with modest to good chemical yields and complete orientational selectivity.
We report herein the design of the asymmetric synthesis of orientational atropisomers via Sonogashira coupling as the key step. This new category of orientational atropisomers is anticipated to have a broad impact on chemical, biomedical, and material sciences in the future.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
Coordinative supramolecular cages with adjustable cavities have found extensive applications in various fields, but the cavity modification strategies for multi‐functional structures are still ...challenging. Here, we present a tension‐driven self‐expansion strategy for construction of multi‐cavity cages with high structural complexity. Under the regulation of strain‐induced capping ligands, unprecedented heteromorphosis triple‐cavity cages S2/S4 were obtained based on a metallo‐organic ligand (MOL) scaffold. The heteromorphosis cages exhibited significant higher cavity diversity than the homomorphous double‐cavity cages S1/S3; all of the cages were thoroughly characterized through various analytical techniques including (1D and 2D) NMR, ESI‐MS, TWIM‐MS, AFM, and SAXS analyses. Furthermore, the encapsulation of porphyrin in the cavities of these multi‐cavity cages were investigated. This research opens up new possibilities for the architecture of heteromorphosis supramolecular cages via precisely controlled “scaffold‐capping” assembly with preorganized ligands, which could have potential applications in the development of multifunctional structures with higher complexity.
A strain‐dependent capping strategy was proposed to obtain a series of multi‐cavity cages, where dimetallic double‐cavity cages and triple‐cavity cages were formed through the geometric matching and the strain‐induced tension, respectively. This is the first time that discrete supramolecular cages with three cavities have been achieved through the application of molecular strain.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
To integrate treatments of photothermal therapy, photodynamic therapy (PDT), and chemotherapy, this study reports on a multifunctional nanocomposite based on mesoporous silica‐coated gold nanorod for ...high‐performance oncotherapy. Gold nanorod core is used as the hyperthermal agent and mesoporous silica shell is used as the reservoir of photosensitizer (Al(III) phthalocyanine chloride tetrasulfonic acid, AlPcS4). The mesoporous silica shell is modified with β‐cyclodextrin (β‐CD) gatekeeper via redox‐cleavable Pt(IV) complex for controlled drug release. Furthermore, tumor targeting ligand (lactobionic acid, LA) and long‐circulating poly(ethylene glycol) chain are introduced via host–guest interaction. It is found that the nanocomposite can specifically target to hepatoma cells by virtue of the LA targeting moiety. Due to the abundant existence of reducing agents within tumor cells, β‐CD can be removed by reducing the Pt(IV) complex to active cisplatin drug for chemotherapy, along with the releasing of entrapped AlPcS4 for effective PDT. As confirmed by in vitro and in vivo studies, the nanocomposite exhibits an obvious near‐infrared induced thermal effect, which significantly improves the PDT and chemotherapy efficiency, resulting in a superadditive therapeutic effect. This collaborative strategy paves the way toward high‐performance nanotherapeutics with a superior antitumor efficacy and much reduced side effects.
Collaborative tumor‐targeted therapy: A highly integrated nanocomposite is constructed based on mesoporous silica‐coated gold nanorods for tumor‐targeted therapy by virtue of the GNR‐mediated PTT, PS‐mediated PDT, and platinum‐based chemotherapy. In vitro and in vivo results confirm that this multifunctional nanocomposite can serve as an ideal platform for tri‐model high‐performance tumor therapy.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
The purpose of this study was to investigate the effects of secreted protein acidic and rich in cysteine (SPARC) on the maintenance of limbal epithelial stem cell (LESC) stemness and restoration of ...ocular surface. To determine the suitable concentration of SPARC for LESC culture, the marker expression, mitogenic effect, and holoclone‐forming capacity of LESCs treated with different concentrations of SPARC were analyzed. To investigate the mechanism of SPARC's action on the preservation of LESCs stemness, the phosphorylation of related signaling pathways was evaluated by Western blotting. A corneal wound model was established to verify the function of SPARC in ocular surface repair. Consecutive subculturing, colony‐forming efficiency, immunofluorescence, and 5‐ethynyl‐2‐deoxyuridine incorporation assays indicated that 1 μg/mL SPARC was a suitable concentration to stimulate LESC proliferation and preserve their proliferative potential. Compared with a control group, 1 μg/mL SPARC effectively increased the expression of ABCG‐2, Bmi‐1, and Ki67, while decreasing that of CK3/12. The mitogenic effect of SPARC on LESCs was found to be mediated by the phosphorylation of c‐Jun N‐terminal kinase (JNK) and p38‐MAPK signaling pathways, whereas the inhibitors of JNK and p38 MAPK reduced the marker expression and mitogenic capacity of LESCs. In a corneal injury model, SPARC facilitated corneal epithelial wound healing and promoted the proliferation of p63α‐positive cells both in the limbus and in the epithelial healing front. SPARC promotes proliferation while suppressing spontaneous differentiation of LESCs through JNK and p38‐MAPK signaling pathways, suggesting that SPARC is a promising factor for the improvement of LESCs culture in vitro and in vivo.
When cultured in medium containing1μg/mL secreted protein acidic and rich in cysteine (SPARC) in vitro, limbal epithelial stem cells (LESCs) showed a greater proliferative and clonogenic capacity and a higher expression of LESCs marker through c‐Jun N‐terminal kinase/p38 MAPK signal pathway. In corneal wounding model, exogenous SPARC accelerated corneal epithelial wound healing and promoted the proliferation of p63α‐positive cells both in limbus and in epithelial healing front.
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