Iridium-promoted deoxyglycoside synthesis: stereoselectivity and mechanistic insight.

Herein, we devised a method for stereoselective -glycosylation using an Ir(i)-catalyst which enables both hydroalkoxylation and nucleophilic substitution of glycals with varying substituents at the C3 position. In this transformation, 2-deoxy-α--glycosides were acquired when glycals equipped with a notoriously poor leaving group at C3 were used; in contrast 2,3-unsaturated-α--glycosides were produced from glycals that bear a good leaving group at C3. Mechanistic studies indicate that both reactions proceed the directing mechanism, through which the acceptor coordinates to the Ir(i) metal in the α-face-coordinated Ir(i)-glycal π-complex and then attacks the glycal that contains the -glycosidic bond in a -addition manner.

Salicylic acid-based nanomedicine with self-immunomodulatory activity facilitates microRNA therapy for metabolic skeletal disorders.

Metabolic skeletal disorders remain a major clinical challenge. The complexity of this disease requires a strategy to address the net effects of both inflammation and impaired bone formation. microRNA-based gene therapy provides several therapeutic advantages to tackle these issues.

Defect Induced Polarization Loss in Multi-Shelled Spinel Hollow Spheres for Electromagnetic Wave Absorption Application.

Defect engineering is an effective approach to manipulate electromagnetic (EM) parameters and enhance absorption ability, but defect induced dielectric loss dominant mechanism has not been completely clarified. Here the defect induced dielectric loss dominant mechanism in virtue of multi-shelled spinel hollow sphere for the first time is demonstrated. The unique but identical morphology design as well as suitable composition modulation for serial spinels can exclude the disturbance of EM wave dissipation from dipolar/interfacial polarization and conduction loss.

Enhanced microwave absorption performance of light weight N-doped carbon nanoparticles.

Microwave absorbents with specific morphology and structure have fundamental significance for tuning microwave absorption (MA). Herein, N-doped carbon sphere nanoparticles and hollow capsules were successfully fabricated oxidative polymerization of dopamine in different mixed solutions, without any template preparation or etching process. Compared to solid particles, the microwave absorbents consisting of N-doped carbon with a hollow structure showed enormously enhanced MA performance, exhibiting a broad effective absorption bandwidth (from 12.

Changes in the fluorescence intensity, degradability, and aromaticity of organic carbon in ammonium and phenanthrene-polluted aquatic ecosystems.

Mixed cultures were established by a sediment to investigate the changes in organic carbon (C) in a combined ammonium and phenanthrene biotransformation process in aquatic ecosystems. The microorganisms in the sediment demonstrated significant ammonium-N and phenanthrene biotransformation capacity with removal efficiencies of 99.96% and 99.

A molecular dynamics study on the mechanical properties of Fe-Ni alloy nanowires and their temperature dependence.

Fe-Ni alloy nanowires are widely used in high-density magnetic memories and catalysts due to their unique magnetic and electrochemical properties. Understanding the deformation mechanism and mechanical property of Fe-Ni alloy nanowires is of great importance for the development of devices. However, the detailed deformation mechanism of the alloy nanowires at different temperatures is unclear.

Organ-on-a-chip: the next generation platform for risk assessment of radiobiology.

Organ-on-a-chip devices have been widely used in biomedical science and technology, for example for experimental regenerative medicine and precision healthcare. The main advantage of organ-on-a-chip technology is the facility to build a specific human model that has functional responses on the level of organs or tissues, thereby avoiding the use of animal models, as well as greatly improving new drug discovery processes for personal healthcare. An emerging application domain for organs-on-chips is the study of internal irradiation for humans, which faces the challenges of the lack of a clear model for risk estimation of internal irradiation.

Giant Piezoresistive Effect and Strong Bandgap Tunability in Ultrathin InSe upon Biaxial Strain.

The ultrathin nature and dangling bonds free surface of 2D semiconductors allow for significant modifications of their bandgap through strain engineering. Here, thin InSe photodetector devices are biaxially stretched, finding, a strong bandgap tunability upon strain. The applied biaxial strain is controlled through the substrate expansion upon temperature increase and the effective strain transfer from the substrate to the thin InSe is confirmed by Raman spectroscopy.

Comparative mitochondrial genomes of four species of and phylogenetic implications (Orthoptera, Melanoplinae).

In this study, the whole mitochondrial genomes (mitogenomes) from four species were sequenced. The complete mitochondrial genomes of , , , and are 15,857 bp, 15,818 bp, 15,843 bp, and 15,872 bp in size, respectively. The 13 protein-coding genes (PCGs) begin with typical ATN codons, except for COXI in , which begins with ACC.

WB : Synthesis, Properties, and Crystal Structure-New Insights into the Long-Debated Compound.

The recent theoretical prediction of a new compound, WB, has spurred the interest in tungsten borides and their possible implementation in industry. In this research, the experimental synthesis and structural description of a boron-rich tungsten boride and measurements of its mechanical properties are performed. The ab initio calculations of the structural energies corresponding to different local structures make it possible to formulate the rules determining the likely local motifs in the disordered versions of the WB structure, all of which involve boron deficit.

NiO/Perovskite Heterojunction Contact Engineering for Highly Efficient and Stable Perovskite Solar Cells.

Recent research shows that the interface state in perovskite solar cells is the main factor which affects the stability and performance of the device, and interface engineering including strain engineering is an effective method to solve this issue. In this work, a CsBr buffer layer is inserted between NiO hole transport layer and perovskite layer to relieve the lattice mismatch induced interface stress and induce more ordered crystal growth. The experimental and theoretical results show that the addition of the CsBr buffer layer optimizes the interface between the perovskite absorber layer and the NiO hole transport layer, reduces interface defects and traps, and enhances the hole extraction/transfer.

Graphitic carbon nitride with thermally-induced nitrogen defects: an efficient process to enhance photocatalytic H production performance.

Graphitic carbon nitride (g-CN, CN) with nitrogen vacancies was synthesized by a controlled thermal etching method in a semi-closed air-conditioning system. The defect-modified g-CN shows an excellent photocatalytic performance demonstrated by water splitting under visible light irradiation. With proper heat-treatment durations such as 2 h (CN2) and 4 h (CN4) at 550 °C, the hydrogen production rates significantly increase to 100 μmol h and 72 μmol h, which are 11 times and 8 times the rate of the pristine CN (8.

Ultrathin δ-MnO nanoflakes with Na intercalation as a high-capacity cathode for aqueous zinc-ion batteries.

Pristine δ-MnO as the typical cathode for rechargeable zinc-ion batteries (ZIBs) suffers from sluggish reaction kinetics, which is the key issue to prepare high-performance manganese-based materials. In this work, Na incorporated into layered δ-MnO (NMO) was prepared for ZIB cathodes with high capacity, high energy density, and excellent durable stability. By an effective fabricated strategy of hydrothermal synthesis, a three-dimensional interconnected δ-MnO nanoflake network with Na intercalation showed a uniform array arrangement and high conductivity.

First-principles calculations of electronic structure and optical and elastic properties of the novel ABX-type LaWN perovskite structure.

The development of ABX-type advanced perovskite materials has become a focus for both scientific researchers and the material genome initiative (MGI). In addition to the traditional perovskite ABO and halide perovskite ABX, LaWN is discovered as a new ABX-type advanced perovskite structure. The elastic and optical properties of this novel LaWN structure are systematically studied DFT.

Application of Lectin Microarrays for Biomarker Discovery.

Many proteins in living organisms are glycosylated. As their glycan patterns exhibit protein-, cell-, and tissue-specific heterogeneity, changes in the glycosylation levels could serve as useful indicators of various pathological and physiological states. Thus, the identification of glycoprotein biomarkers from specific changes in the glycan profiles of glycoproteins is a trending field.

Metallo-supramolecular complexes from mPEG/PDPA diblock copolymers and their self-assembled strip nanosheets.

Herein we designed and synthesized mPEG/PDPA copolymers containing two 4-([2,2':6',2''-terpyridin]-4'-yl) phenyl (Tpyp) groups at the junction point of the two blocks (mPEG(--Tpyp)--PDPA , = 23, 33, and 44). Interestingly, after a hierarchical pattern from the coordination of mPEG(--Tpyp)--PDPA with Ru(ii) ions followed by the self-assembly in water, 2D strip nanosheets with a monomolecular layer were obtained. In contrast, mPEG(--Tpyp)--PDPA without coordination self-assembled into spherical micelles in the similar condition.

Multi-factor study of the effects of a trace amount of water vapor on low concentration CO capture by 5A zeolite particles.

Water vapor is ubiquitous and affects the performance of an adsorbent. In this work, a grand-canonical Monte Carlo method (GCMC) combining with dispersion-corrected density functional theory (DC-DFT) calculation is adopted to investigate the effect of a trace amount of water vapor on low concentration CO capture in 5A zeolite particles. The force field parameters for the interactions among CO, water, and 5A zeolite are obtained DC-DFT calculations.

Thickness-dependent fast wetting transitions due to the atomic layer deposition of zinc oxide on a micro-pillared surface.

Smart surfaces promote the fundamental understanding of wetting and are widely used in practical applications for energy and water collection. Light-induced switchable wettability facilitated by ZnO coatings, for instance, was developed for liquid manipulation at the surface. However, the transition of wetting states was reported to follow a hydrophobic-hydrophilic cycle in an hour, which is very long and may limit its future applications.

Flexible pH sensor based on a conductive PANI membrane for pH monitoring.

pH is a critical parameter used to specify the acidity or alkalinity of an aqueous solution in chemistry, food processing, and medical care. In this study, a conductimetric-type micro pH sensor has been achieved using PANI membrane fabricated on a flexible substrate film aiming to monitor wound healing. The sensor is based on the incorporation of a polyaniline (PANI) membrane, interdigital electrode, and polyimide (PI) substrate.

Uncovering Structural Opportunities for Zirconium Metal-Organic Frameworks via Linker Desymmetrization.

The discovery of metal-organic frameworks (MOFs) mimicking inorganic minerals with intricate topologies requires elaborate linker design guidelines. Herein, the concept of linker desymmetrization into the design of tetratopic linker based Zr-MOFs is applied. A series of bent tetratopic linkers with various substituents are utilized to construct Zr-MOFs with distinct cluster connectivities and topologies.

Thermal behavior and combustion of Al nanoparticles/ MnO-nanorods nanothermites with addition of potassium perchlorate.

To explore the effect of potassium perchlorate (KClO) on Al nanoparticles/MnO-nanorods nanothermite systems, in this paper, Al/MnO nanothermites with different mass fraction of KClO were prepared by electrospray. The samples were characterized by XRD, SEM, TG-DSC analysis. According to the results of TG-DSC, the addition of KClO seemed to cause no direct improvement on their exothermic reactions.

A supramolecular hydrophobic guest transport system based on a biological macrocycle.

A protein-based macrocyclic bioactive guest loading system has been developed, which not only provides a stable 10 nm scale lipophilic environment, but also increases the solubility of potent anticancer agent SN38 in its active lactone form in aqueous medium.

Preparation and microwave absorption performance of a flexible FeO/nanocarbon hybrid buckypaper and its application in composite materials.

Graphene oxide (GO) and carbon nanotubes are promising microwave-absorbing materials. Herein, ferroferric oxide (FeO)/multiwall carbon nanotube (MWCNT) and FeO/GO hybrid buckypapers with excellent flexibility and manoeuvrability were coated on the surface of an epoxy substrate to fabricate microwave-absorbing composites. FeO/GO buckypapers show a unique layered structure that differs from the complex network structure of FeO/MWCNT buckypapers.

MicroRNAs and long noncoding RNAs: new regulators in cell fate determination of mesenchymal stem cells.

Mesenchymal stem cells (MSCs) are multipotent cells that are able to differentiate into numerous cell types, including well-known inherent osteoblasts, adipocytes, and chondrocytes, and other cell types, such as hepatocytes, cardiomyocytes and nerve cells. They have become a favorite source of cell-based therapy. Therefore, knowing the mechanism that determines the cell fate of MSCs is important not only for deep understanding of the MSC function but also for the manipulation of MSCs for clinical application.