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Pseudomonas aeruginosa is of major concern for cystic fibrosis patients where this infection can be fatal. With the emergence of drug-resistant strains, there is an urgent need to develop novel antibiotics against P. aeruginosa. MurB is a promising target for novel antibiotic development as it is involved in the cell wall biosynthesis. MurB has been shown to be essential in P. aeruginosa, and importantly, no MurB homologue exists in eukaryotic cells. A fragment-based drug discovery approach was used to target Pa MurB. This led to the identification of a number of fragments, which were shown to bind to MurB. One fragment, a phenylpyrazole scaffold, was shown by ITC to bind with an affinity of Kd = 2.88 mM (LE 0.23). Using a structure guided approach, different substitutions were synthesized and the initial fragment was optimized to obtain a small molecule with Kd = 3.57 μM (LE 0.35).Direct assembly of high-quality single-crystal perovskite microarrays on transparent conductive substrates and carrier injection layers is vital to realize high-performance optoelectronic devices. Although cubic-phase CsPbBr3 is considered to have a higher structural and optical quality than the orthorhombic one, obtaining a well-aligned assembly directly on the aforementioned substrates is still challenging. Here we developed a solvent-assisted crystallization strategy with the assistance of surface modifiers, through which the in situ low-temperature growth of well-aligned cubic single-crystal CsPbBr3 microarray with a preferential out-of-plane [100] orientation is achieved for the first time on commercial transparent conductive substrates. As compared with the control orthorhombic samples, the cubic CsPbBr3 single crystals possess superior properties including a higher photoluminescence internal quantum efficiency, fewer defect states, a weaker scattering by phonons, and an appearance of lasing. The results presented here can pave the way for future design and applications of optoelectronic devices based on perovskite microarrays.A copper-catalyzed alkene-trifluoromethylation-triggered nitrile insertion/remote functionalization relay process has been achieved, in which "interrupted" remote 1,n-difunctionalizations of alkenes with nitrile insertion can deliver iminyl radical intermediates instead of C-based radicals, followed by subsequent 1,n-HAT to furnish corresponding remote functionalization. This relay protocol enables a straightforward approach to streamline the assembly of structurally diverse trifluoromethylated azaheterocycles.Methylation changes at cytosine-guanine dinucleotide (CpG) sites in genes are closely related to cancer development. Thus, detection and quantification of low-abundance methylated DNA is critical for early diagnosis. Here, we report an atomic force microscopy (AFM)-based quantification method for DNA that contains methyl-CpG at a specific site, without any treatment to the target DNA such as chemical labeling, fluorescence tagging, or amplification. We employed AFM-tip-tethered methyl-CpG-binding proteins to probe surface-captured methylated DNA. We observed a linear correlation (R2 = 0.982) between the input copy number and detected copy number, in the low copy number regime (10 or fewer; subattomolar concentrations). For a mixture of methylated and nonmethylated DNA that resembles clinical samples, we were still able to quantify the methylated DNA. These results highlight the potential of our force-mapping-based quantification method for wide applications in early detection of diseases associated with methylated DNA.Pd has been regarded as one of the alternatives to Pt as a promising hydrogen evolution reaction (HER) catalyst. Strategies including Pd-metal alloys (Pd-M) and Pd hydrides (PdHx) have been proposed to boost HER performances. However, the stability issues, e.g., the dissolution in Pd-M and the hydrogen releasing in PdHx, restrict the industrial application of Pd-based HER catalysts. We here design and synthesize a stable Pd-Cu hydride (PdCu0.2H0.43) catalyst, combining the advantages of both Pd-M and PdHx structures and improving the HER durability simultaneously. The hydrogen intercalation is realized under atmospheric pressure (1.0 atm) following our synthetic approach that imparts high stability to the Pd-Cu hydride structure. The obtained PdCu0.2H0.43 catalyst exhibits a small overpotential of 28 mV at 10 mA/cm2, a low Tafel slope of 23 mV/dec, and excellent HER durability due to its appropriate hydrogen adsorption free energy and alleviated metal dissolution rate.For gaining insights into interactions in periodic systems, an analysis is developed based on the fragment molecular orbital method combined with periodic boundary conditions. The adsorption energy is decomposed into guest and surface polarization and deformation energy, guest-surface and guest-guest interactions, and the vibrational free energy. The analysis is applied to the adsorption of guest molecules to Ih (001) ice surface. The cooperativity effects result in a non-linear change in the adsorption energy with coverage due to many-body effects. The role of dispersion is found to be dominant for guests with long hydrophobic tails. A rule is proposed relating the length of the alkyl tail with the formation of the guest layer. The computed binding enthalpies are in good agreement with experimental values. For high coverage, adsorbed molecules can form an ordered layer known as self-assembled monolayer.The first example of divergent N-heterocycle syntheses through a copper-catalyzed three-component reaction of α,β-unsaturated ketoximes, paraformaldehyde, and amines has been documented. In particular, this divergent synthetic strategy was achieved by controlling the reaction conditions to afford the corresponding imidazoles and dihydroimidazoles in moderate to good yields with a broad substrate scope and good functional group compatibility.We present a benchmark study of density functional approximation (DFA) performances in predicting the two-photon-absorption strengths in π-conjugated molecules containing electron-donating/-accepting moieties. A set of 48 organic molecules is chosen for this purpose, for which the two-photon-absorption (2PA) parameters are evaluated using different DFAs, including BLYP, PBE, B3LYP, PBE0, CAM-B3LYP, LC-BLYP, and optimally tuned LC-BLYP. Minnesota functionals and ωB97X-D are also used, applying the two-state approximation, for a subset of molecules. The efficient resolution-of-identity implementation of the coupled-cluster CC2 model (RI-CC2) is used as a reference for the assessment of the DFAs. Two-state models within the framework of both DFAs and RI-CC2 are used to gain a deeper insight into the performance of different DFAs. Our results give a clear picture of the performance of the density functionals in describing the two-photon activity in dipolar π-conjugated systems. The results show that global hybrids are best suited to reproduce the absolute values of 2PA strengths of donor-acceptor molecules. The range-separated functionals CAM-B3LYP and optimally tuned LC-BLYP, however, show the highest linear correlations with the reference RI-CC2 results. Hence, we recommend the latter DFAs for structure-property studies across large series of dipolar compounds.The application of solid-state batteries (SSBs) is challenged by the inherently poor interfacial contact between the solid-state electrolyte (SSE) and the electrodes, typically a metallic lithium anode. Building artificial intermediate nanofilms is effective in tackling this roadblock, but their implementation largely relies on vapor-based techniques such as atomic layer deposition, which are expensive, energy-intensive, and time-consuming due to the monolayer deposited per cycle. Herein, an easy and low-cost wet-chemistry fabrication process is used to engineer the anode/solid electrolyte interface in SSBs with nanoscale precision. This coordination-assisted deposition is initiated with polyacrylate acid as a functional polymer to control the surface reaction, which modulates the distribution and decomposition of metal precursors to reliably form a uniform crack-free and flexible nanofilm of a large variety of metal oxides. For demonstration, artificial Al2O3 interfacial nanofilms were deposited on a ceramic SSE, typically garnet-structured Li6.5La3Zr1.5Ta0.5O12 (LLZT), that led to a significant decrease in the Li/LLZT interfacial resistance (from 2079.5 to 8.4 Ω cm2) as well as extraordinarily long cycle life of the assembled SSBs. This strategy enables the use of a nickel-rich LiNi0.83Co0.07Mn0.1O2 cathode to deliver a reversible capacity of 201.5 mAh g-1 at a considerable loading of 4.8 mg cm-2, featuring performance metrics for an SSB that is competitive with those of traditional Li-ion systems. Our study demonstrates the potential of solution-based routes as an affordable and scalable manufacturing alternative to vapor-based deposition techniques that can accelerate the development of SSBs for practical applications.Colloidal molecules are designed to mimic their molecular analogues through their anisotropic shape and interactions. However, current experimental realizations are missing the structural flexibility present in real molecules thereby restricting their use as model systems. We overcome this limitation by assembling reconfigurable colloidal molecules from silica particles functionalized with mobile DNA linkers in high yields. We achieve this by steering the self-assembly pathway toward the formation of finite-sized clusters by employing high number ratios of particles functionalized with complementary DNA strands. The size ratio of the two species of particles provides control over the overall cluster size, i.e., the number of bound particles N, as well as the degree of reconfigurability. The bond flexibility provided by the mobile linkers allows the successful assembly of colloidal clusters with the geometrically expected maximum number of bound particles and shape. We quantitatively examine the self-assembly dynamics of these flexible colloidal molecules by a combination of experiments, agent-based simulations, and an analytical model. Our "flexible colloidal molecules" are exciting building blocks for investigating and exploiting the self-assembly of complex hierarchical structures, photonic crystals, and colloidal metamaterials.A series of steroidal piperidone derivatives were synthesized, and their agricultural activities were evaluated against Myzus persicae, Aphis citricola, Brevicoryne brassicae Linn., and Bemisia tabaci (Gennadius). Most of the tested compounds exhibited potent insecticidal activity against these four pests. Compound I-9 displayed the highest activity against M. persicae, A. citricola, and Brevicoryne brassicae, with LC50 values of 11.3, 10.4, and 8.68 μg/mL, respectively. The mode of action test indicated that these derivatives had superior contact and systemic insecticidal activity against M. IMT1 persicae. In addition, we initially explored whether the foregut and midgut might be the action sites of the target derivatives against M. persicae. Furthermore, a field trial showed that the control of compound I-9 was similar to that of acetamiprid against M. persicae, at a dose of 50 μg/mL; the control rates were 97.8 and 99.2% after 14 and 21 days, respectively. The structure-activity relationship of these analogues provided some important insights for the discovery and development of new insecticides to solve the current pesticide resistance crisis.

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