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Germanium has been recognized as a promising anode material for lithium-ion batteries (LIBs) due to its high theoretical capacity and excellent lithium-ion diffusivity. Nonetheless, it is challenging to enhance both the high-rate performance and long-term cycling stability simultaneously. This study introduces a novel heterostructure composed of germanium nanosheets integrated with graphene (Ge NSs@Gr). These nanosheets undergo an in situ phase transformation from a hydrogen-terminated multilayer germanium compound termed germanane (GeH) derived via topochemical deintercalation from CaGe 2 . This approach mitigates oxidation and prevents restacking by functionalizing the exfoliated germanane with octadecenoic organic molecules. The resultant germanium nanosheets retain their structural integrity from CaGe 2 and present an exposed, active (111) surface that features an open crystal lattice, facilitating swift lithium-ion migration conducive to lithium storage. The composite material delivers a substantial reversible capacity of 1220 mA h g -1 at a current density of 0.2 C and maintains a capacity of 456 mA h g -1 even at an ultrahigh current density of 10 C over extended cycling. Impressively, a capacity of 316 mA h g -1 remains after 5000 cycles. The exceptional high-rate performance and durable cycling stability underscore the Ge NSs@Gr anode's potential as a highly viable option for LIBs.

Fragment growing is an important ligand design strategy in drug discovery. In this study, we present FragGrow, a web server that facilitates structure-based drug design by fragment growing. FragGrow offers two working modes: one for growing molecules through the direct replacement of hydrogen atoms or substructures and the other for growing via virtual synthesis. FragGrow works by searching for suitable fragments that meet a set of constraints from an indexed 3D fragment database and using them to create new compounds in 3D space. The users can set a range of constraints when searching for their desired fragment, including the fragment's ability to interact with specific protein sites; its size, topology, and physicochemical properties; and the presence of particular heteroatoms and functional groups within the fragment. We hope that FragGrow will serve as a useful tool for medicinal chemists in ligand design. The FragGrow server is freely available to researchers and can be accessed at https://fraggrow.xundrug.cn.

An iterative approach between machine learning (ML) and laboratory experiments was developed to accelerate the design and synthesis of environmental catalysts (ECs) using selective catalytic reduction (SCR) of nitrogen oxides (NO x ) as an example. The main steps in the approach include training a ML model using the relevant data collected from the literature, screening candidate catalysts from the trained model, experimentally synthesizing and characterizing the candidates, updating the ML model by incorporating the new experimental results, and screening promising catalysts again with the updated model. This process is iterated with a goal to obtain an optimized catalyst. Using the iterative approach in this study, a novel SCR NO x catalyst with low cost, high activity, and a wide range of application temperatures was found and successfully synthesized after four iterations. The approach is general enough that it can be readily extended for screening and optimizing the design of other environmental catalysts and has strong implications for the discovery of other environmental materials.

3,4-Hydroxypyridinone (3,4-HOPO) is a vital metal-chelating pharmacophore. However, the efficient synthesis has been a long-standing problem in drug development. In this paper, we report an efficient electrophilic activation of unprotected maltols via reversible covalent bonds between boronic acid and 3-hydroxyl/4-carbonyl. This one-pot reaction proceeded well on a gram scale in water with excellent efficiencies up to 97%. Moreover, taking advantage of the covalent interactions via the transient boronate, most of the previously tough amine donors, including sterically hindered amines, aromatic amines, and amino acids and amino alcohols, were well-tolerated. Importantly, the potential of this strategy in the pharmaceutical industry was highlighted with a successful synthesis of 3,4-HOPOs containing iron-chelating active pharmaceutical ingredients on 10 g and kilogram scales.

Mitogen-activated protein kinase FgGpmk1 plays vital roles in the development and virulence of Fusarium graminearum ( F. graminearum ), the causative agent of Fusarium head blight (FHB). However, to date, the druggability of FgGpmk1 still needs verification, and small molecules targeting FgGpmk1 have never been reported. Here, we reported the discovery of a novel inhibitor 94 targeting FgGpmk1. First, a novel hit (compound 21 ) with an EC 50 value of 13.01 μg·mL -1 against conidial germination of F. graminearum was identified through virtual screening. Then, guided by molecular modeling, compound 94 with an EC 50 value of 3.46 μg·mL -1 was discovered, and it can inhibit the phosphorylation level of FgGpmk1 and influence the nuclear localization of its downstream FgSte12. Moreover, 94 can inhibit deoxynivalenol biosynthesis without any damage to the host. This study reported a group of FgGpmk1 inhibitors with a novel scaffold, which paves the way for the development of potent fungicides to FHB management.

We successfully designed and obtained a new family of polyoxometalates (POMs) containing mixed-metal elements and a trialkoxyl (TRIS) ligand via a very simple one-pot process under mild condition. Single-crystal X-ray diffraction revealed that this family belongs to compact Lindqvist-type hexatungstovanadates. In particular, the hydroxyl-containing product can be further functionalized through esterification. Not only does this work open a broad door for unusual POM clusters involving vanadium and tungsten atoms in the future, but also the design concept of this work also provides new insight for the synthesis and further exploration of POMs.

Heterogeneity in physical and chemical properties is a common characteristic in a subsurface environment. This study investigated the effect of physico-chemical heterogeneity on arsenic (As) sorption and reactive transport under water extraction in a layered system with preferential flow paths. A flume experiment was performed to derive the spatio-temporal data of As reactive transport. The results indicated that the heterogeneous system significantly accelerated downward (vertical direction) As migration as a coupled effect of physical and chemical heterogeneity that led to fast As transport with low As sorption along the preferential flow paths. The results also indicated that such a heterogeneity effect was driven by water extraction that enhanced the downward groundwater flow along the preferential flow paths. Numerical simulations were performed by matching the experimental results to provide insights into the dominant processes controlling the As migration in the heterogeneous systems. The simulation results highlighted the importance of the kinetic oxidation of mineral-bonded Fe(II) to Fe(III) in the clay matrix that dynamically increased As sorption affinity and retarded As reactive transport. A coupled model of reactive transport along the preferential flow paths, sorption-retarded diffusion from the preferential flow paths into the clay matrixes, and reactions that change sorption affinity in the matrix was required to describe the As reactive transport systems with physico-chemical heterogeneities. The results have strong implications for understanding and modeling As downward migration from shallow to deep aquifers under groundwater pumping conditions in field systems with inherent heterogeneity.

The stability of plasma-sprayed hydroxyapatite (HA) coatings on metallic implants in vivo remains a significant challenge for load-bearing orthopedic implants despite their excellent mechanical and osteoconductive properties. This study focuses on oxide layer formation on the surface of Ti6Al4V samples through furnace heating at 600, 700, and 800 °C for 10 min for optimization of the most effective oxide layer to increase plasma coating crystallinity and improve plasma coating bond strength with the metal surface. The 800 °C heat treatment shows an effective oxide layer which increases coating crystallinity from 64 to 75% and coating adhesive bond strength from 25.9 ± 2.3 to 30.7 ± 1.1 MPa, while simultaneously reducing the dissolution rate of HA coatings. The addition of biologically relevant dopants, MgO and SiO 2 , show negligible effects on crystallinity and adhesive bond strength on plasma-sprayed HA coatings and additionally show an enhancement effect on osteoblast proliferation and differentiation. Moreover, the inclusion of these additivess shows an increase in osteogenesis in a rat distal femur model after 6 and 10 weeks of implantation. Overall, this study provides a direct solution to improve the crystallinity, adhesive bond strength, and osteogenic properties of plasma-sprayed HA coatings on orthopedic implants that is more manufacturable and translational from research to an industrial scale.

Biofilms can cause many bacterial diseases, such as dental disease. An in vitro detection of biofilms may help to screen antibiofilm drugs. An impedance measurement based on an Au electrode has been successfully used for in vitro real-time monitoring of animal and human cell growth. However, microbial growth on the Au electrode produced a poor signal because of the small size of microbial cells. We have recently demonstrated that graphene derivatives can be produced on a carbon electrode through facile electrochemical activation, thus forming a reduced graphene oxide-carbon electrode (rGO-CE). Based on this fact, we hypothesized that an in vitro formed rugose graphene layer of rGO-CE may provide a large surface area for the growth of microbial biofilms and can therefore produce a strong impedance signal in response to a change in the biomass. In this study, three oral bacteria, Streptococcus mutans ( S. mutans ), Actinomyces viscosus ( A. viscosus ), and Lactobacillus fermentum ( L. fermentum ), were cultured on the surfaces of rGO-CE. As a result, the impedance response signal of the rGO-CE for the growth of S. mutans and A. viscosus was found to be 3.3 times and 6.0 times stronger than that of the Au electrode at 1.17 and 54.7 kHz, respectively. In particular, the poorly adhering strain of L. fermentum also produced a detectable signal on the graphene electrode but not on the Au electrode at 1.17 kHz. Furthermore, destructions of the biofilms grown on the rGO-CE by cetylpyridinium chloride were successfully monitored by impedance changes. Overall, it is promising to develop a graphene-based impedance biosensor platform for biofilm study and antibiofilm drug screening.

The adsorption of CO 2 by conventional liquid alkanolamine adsorbents does not meet the requirements for green-friendly development in industrial applications. In this work, we constructed NH 2 -β-CD-MOF for the first time through the amino-functionalization of the lowest-priced, readily available, and biocompatible β-CD. Subsequently, the samples were characterized by single-crystal X-ray diffraction, powder X-ray diffraction, scanning electron microscopy, differential scanning calorimetry, thermogravimetric analysis, elemental analysis, and N 2 adsorption/desorption. The CO 2 adsorption capacity of NH 2 -β-CD-MOF was found to be 12.3 cm 3 /g, which is 10 times that of β-CD-MOF. In addition, NH 2 -β-CD-MOF has outstanding selective adsorption of CO 2 /N 2 (947.52) compared with the reported materials. The adsorption mechanism of CO 2 was analyzed by X-ray photoelectron spectroscopy and Fourier transform infrared spectroscopy. Furthermore, we have found that NH 2 -β-CD-MOF has better water stability relative to β-CD-MOF and γ-CD-MOF, and it can be recycled by an ultrasonic method.

Inspired by animal muscles, we developed a kind of tough elastomers combining high strength and high stretchability with autonomous self-healing capability. A key structural feature is the construction of a double network (DN) connected by the hydrogen bond and host-guest interactions. The first network is the classic elastomer polyacrylate matrix cross-linked by strong hydrogen bonding. The second network is formed through the host-guest interactions between polycyclodextrin and the adamantane (Ad) groups on the side of the polyacrylate chain. Supramolecular interactions between two networks make them miscible and interpenetrate in the molecular level and then can share the load as the sample was stretched. The host-guest interactions act not only as sacrificial bonds for energy dissipation but also as self-healing driving forces. The tensile strength of the DN elastomer reaches about 6.7 MPa and the strain is as high as about 950%. The DN elastomer can be easy to repair by touching the damaged surface together at ambient conditions when broken or cut. The recovered tensile strength can reach over 4.5 MPa, which is better than the most pristine strength of existing spontaneous self-healing elastomers.

Osteoporosis is one of the most commonly identified bone disorders, which leads to an enhanced risk of bone fracture, especially for the older population. Hydroxyapatite (HA) coated titanium (Ti) alloys have been used widespread for load bearing applications like hip or knee replacements owing to their compositional similarity to natural bone; however, incorporation of osteoinductivity is still a challenge. The objective of this study is to evaluate the effects of SiO 2 and ZnO as dopants in HA coated Ti alloys on cellular osteoporotic conditions mimicked by an in vitro  osteoblast and osteoclast coculture model. HA, Si-HA, and Zn-HA coatings showed adhesive bond strengths of 25.7 ± 1.9 MPa, 23.8 ± 2.3 MPa, and 22.9 ± 3.5 MPa, respectively. To study the effects of doped HA coatings on the simulated osteoporotic cellular condition, human mesenchymal stem cells (hMSCs) and monocytes (THP-1) were seeded simultaneously in a ratio of 1:4, respectively. Gene expressions studies were carried out with marker genes showing that the presence of the dopants in the HA coating enhanced osteoblast proliferation along with diminishing cell growth of osteoclasts. This study demonstrates the promising effects of SiO 2 and ZnO in plasma sprayed HA coatings on alleviating osteoporosis cellular conditions, which can potentially be used for load-bearing implants in aging patients whose bone resorption is more dominant than bone formation.

Plasma-sprayed hydroxyapatite (HA)-coated titanium implants have been widely used in orthopedic applications due to their inheritance of an excellent mechanical property from titanium and great osteoconductivity from HA. However, the lack of osteoinductivity limits their further applications. In this study, 1 wt % MgO and 0.5 wt % SiO 2 were mixed with HA for making plasma-sprayed coatings on titanium implants. Plasma-sprayed HA- and MgO/SiO 2 -HA-coated titanium implants showed adhesive bond strengths of 25.73 ± 1.92 and 23.44 ± 2.89 MPa, respectively. The presence of MgO and SiO 2 significantly increased the osteogenesis, osseointegration, and bone mineralization of HA-coated titanium implants by the evaluation of their histomorphology after 6, 10, and 14 weeks of implantation in rat distal femoral defects. Implant pushout tests also showed a shear modulus of 149.83 ± 3.69 MPa for MgO/SiO 2 -HA-coated implants after 14 weeks of implantation, compared to 52.68 ± 10.41 MPa for uncoated implants and 83.92 ± 3.68 MPa for pure HA-coated implants; These are differences in the shear modulus of 96% and 56.4%, respectively. This study assesses for the first time the quality of the bone-implant interface of induction plasma-sprayed MgO and SiO 2 binary-doped HA coatings on load-bearing implants compared to bare titanium and pure HA coatings in a quantitative manner. Relating the osseointegration and interface shear modulus to the quality of implant fixation is critical to the advancement and implementation of HA-coated orthopedic implants.

The interaction between dodecyltrimethylammonium bromide (DTAB) and curcumin has been studied in pH 5.0 sodium phosphate buffer using absorption and fluorescence measurements. With increasing DTAB concentration (C(DTAB)) from 0 to 20 mM, the absorption peak of curcumin at 430 nm, corresponding to the conjugated structure of curcumin, first weakens gradually into a shoulder but increases back into one peak with much higher absorption intensity. On the contrary, as C(DTAB) increases, the initial small absorption shoulder of curcumin at 355 nm, corresponding to the feruloyl unit of curcumin, first increases gradually into a clear peak but decreases back into one shoulder until almost disappeared finally. By remaining at nearly the same wavelength, the fluorescence of curcumin first decreases at C(DTAB) lower than 5 mM and then increases gradually up to C(DTAB) = 10 mM, which is followed by sharp increases of fluorescence intensity with marked blue-shifts at higher C(DTAB). The values of anisotropy and microviscosity of curcumin obtained from the fluorescence polarization technique also showed pronounced changes at different surfactant concentrations. The interaction mechanisms of DTAB with curcumin have been presented at low, intermediate, and high surfactant concentrations, which is relating to interaction forces, surfactant aggregations, as well as structural alterations of curcumin., (© 2011 American Chemical Society)

We report that two molecular building blocks differ only by two protons, yet they form totally different nanostructures. The protonated one self-organized into hollow nanospheres (~200 nm), whereas the one without the protons self-assembled into rectangular plates. Consequently, the geometrically defined nanoassemblies exhibit radically different properties. As self-assembly directing units, protons impart ion-pairing and hydrogen-bonding probabilities. The plate-forming nanosystem fluoresces weakly, probably due to energy transfer among chromophores (Φ < 0.2), but the nanospheres emit strong yellow fluorescence (Φ ≈ 0.58-0.85).

Microspheric and lamellar BiVO(4) powders were selectively prepared through a hydrothermal process by using cetyltrimethylammonium bromide (CTAB) as a template-directing reagent. The as-prepared BiVO(4) powders were characterized by X-ray diffraction, electron microscopy, nitrogen adsorption-desorption experimentation, Fourier transform infrared spectrometry, and UV-vis diffuse reflectance spectroscopy. Experimental results indicate that microspheric BiVO(4) with particle sizes in the range of 7-12 microm can be derived from a relatively low hydrothermal temperature (