Notes

Comparison regarding breathed in mannitol/dornase alfa mixture and daily dornase alfa on it's own in kids using cystic fibrosis.
Apart from revealing a general mechanism of NP binding-induced membrane pore formation, our results provide the reference for improving the endosomal escape of nanoparticles through manipulating their morphology, a direction that can be explored either independently or combined with existing strategies targeting NP surface chemistry.Polynuclear silver clusters are described that unexpectedly transform from cyclic trinuclear complexes (CTCs) upon reacting with σ-donating phenylacetylene, featuring a noria-like conformation. The introduction of foreign copper ions leads to isomorphic bimetallic Ag/Cu clusters, with a boost in the photoluminescence quantum yield relative to the original silver clusters.A rotaxane composed of a symmetrical axle containing three binding stations and a cone-like macrocycle containing two secondary amines has been investigated at the atomic level. At high pH, the macrocycle binds to the intermediate di(quaternary ammonium) site, while at low pH, the protonated macrocycle selectively moves along the axle to one of the two symmetrical phenyl triazole binding sites facing its upper rim, but does not shuttle backward. The determined free-energy profile characterizing the translocation of the macrocycle indicates that the selected binding site is energetically more favorable than the one facing the lower rim of the macrocycle and the free-energy barrier against translocation to the former site is lower than to the latter one, rationalizing the directional movement. This selectivity mainly stems from the asymmetry of the macrocycle shape. The strong electrostatic repulsion between the ring and the axle is found to constitute the driving force for the shuttling of the ring and also the resistance for its reverse motion. Moreover, the effect of the solvent on the shuttling has been examined, suggesting that increasing the solvent polarity may weaken the directional preference of shuttling, due to the shielding effect of polar solvents on electrostatic interactions. Our study provides a theoretical framework for tuning the selectivity of directional movement in molecular machines.Towards precisely controlled nanostructure growth, patterned substrates are used as templates to direct heteroepitaxial self-assembly. This affects the size, shape and ordering of nanostructures, which are formed as a consequence of the mismatch in strain. In the well-studied case of Si-Ge heteroepitaxy on Si, the lattice mismatch leads to spontaneous formation of quantum dots. On patterned substrates, the competition between the length scale of the pattern and the intrinsic quantum dot size leads to rich behavior, where the localization of dots can be modified with respect to the features of the patterns. We show by continuum modeling that, in cubic elastic materials such as silicon and germanium, there is also a competition between the pattern orientation and the elastically soft directions of the film, which affects the precise location of quantum dots on the surface. When the pattern is between the elastically soft directions, the quantum dots can form purely in the narrow region directly between two neighboring pits, referred to as the saddle region. On the other hand, when the pattern is along the elastically soft directions, the quantum dots prefer to form in the region at the centre of four pits, referred to as the crown region. This resolves a discrepancy between theory and experiments and gives another dimension to control quantum dot formation in strained nanocrystalline systems.The chemical composition of water-soluble organics in oil sands process-affected water (OSPW) is primarily composed of natural constituents of bitumen that are solubilized and concentrated during aqueous extraction of oil sands. OSPW organics are persistent and acutely toxic, and a leading remediation strategy is long-term ageing in end-pit lakes, despite limited data available on its photochemical fate. Here, direct photolysis of whole OSPW, or of its constituent fractions, was examined at environmentally relevant wavelengths (>290 nm) in bench-top studies. Changes in the chemical profiles of whole OSPW, acid- (AEO), and base-extractable organics (BEO) were characterized by liquid chromatography with ultra-high resolution mass spectrometry in negative (-) and positive (+) ionization modes. Following 18 d of irradiation, photolysis reduced the total ion intensity in all samples in both modes. The most photo-labile species included the O2-, O3-, O4-, O2S-, and O4S- chemical classes, which were depleted in whole OSPW by 93-100% after only 5 d. In positive mode, detected species were more recalcitrant than those detected in negative mode, with an average reduction across all heteroatomic classes of 75 ± 11.0% after 18 d. Estimated environmental half-lives for heteroatomic classes ranged from 57 d (O4S-) to 545 d (O3N+), with a greater recalcitrance for classes detected in positive mode compared to negative mode. Under field conditions in end-pit lakes, natural photolysis may be an important mechanism for effective OSPW remediation, and we suggest that future end-pit lakes be shallow to maximize light penetration and natural photolysis in ageing OSPW.Water splitting using semiconductor photoelectrodes is a promising approach to solar hydrogen production. Previous studies have well-demonstrated that electrochemical reduction (ER) pretreatment of bare and Ti-doped α-Fe2O3 electrodes enhances water photooxidation efficiencies, however, the mechanism underlying this improvement remains poorly understood. In this study, this was quantitatively investigated by multiple photoelectrochemical techniques and transient absorption spectroscopy, using the doped electrodes as examples. The results reveal that the kinetics of photoholes after moving to the electrode surface can be well described by a model of surface-state mediated charge transfer and recombination. The reason for the photocurrent enhancement is attributed to a significantly increased charge transfer rate constant (kct) and a decreased surface recombination rate constant (ksr) by ER. The reason for the accelerated kct is that a new type of surface state, with a favorable energy position for water oxidation, is produced. The decreased ksr is due to the reduced electron density at the surface of the semiconductor, resulted predominately from the negatively shifted flat band potential. These findings provide new insights into the mechanism of water photooxidation and enlighten a simple way to develop more efficient electrodes.In comparison with conventional therapies, nanomedicine shows prominent clinical performance, with better therapeutic efficacy and less off-target toxicity. As an important component of nanomedicine, gold nanoparticle (GNP)-based nanodrugs have attracted considerable interest because of their excellent performance given by the unique structure. Although no pharmaceutical formulations of GNP-associated nanodrugs have been officially marketed yet, a substantial amount of research on this aspect is being carried out, producing numerous GNP-based drug delivery systems with potential clinical applications. In this review, we present an overview of our progress on GNP-based nanodrugs combined with other achievements in biomedical applications, including drug-conjugated GNPs prepared for disease treatments and specific tumour targeting, structure-efficacy relationship (SER) studies on GNP-conjugated nanodrugs, and therapeutic hybrid nanosystems composed of GNPs. In addition, we also put forward some proposals to guide future work in developing GNP-based nanomedicine. We hope that this review will offer some useful experience for our peers and GNP-based nanodrugs will be utilized in the clinic with further persistent efforts.In heterogeneous catalysis, surface hydroxylation is well recognized as a common phenomenon under realistic reaction conditions. However, even for the versatile ceria-based materials that have attracted extensive studies, the results and causes of the hydroxyl effect on the catalytic reactivity remain largely elusive. In this work, density functional theory calculations corrected by on-site Coulomb interaction were conducted to clarify the CO oxidation pathways and also the impacts of surface hydroxyls on the catalytic performance at the two most stable reconstructions of CeO2(100). It is found that the presence of hydroxyl groups can boost the CO oxidation activity on the O-terminal surface but shows an opposite effect on the CeO4-terminal one. Further analyses regarding the structural distortions, electronic structures and orbital interactions reveal that the stretched Ce-O distance via in-plane hydrogen bonds and the electron redistributions induced by additional hydroxyl coordination are the main reasons for the different hydroxyl effects on the O- and CeO4-terminal surfaces. Our results not only uncover the dual-character of surface hydroxyls in heterogeneous catalysis, but they also underline the significance of moderate moisture in the reaction system that may endow ceria catalysts with both good thermostability and high catalytic activity.Herein, we report a highly facile and unprecedented approach to synthesize congested N-(hetero)aryl amines en route to α-amino acid amides using α-bromoamides as alkylating agents under mild reaction conditions (room temperature). The involvement of aza-oxyallyl cations as alkylating agents is the hallmark of this reaction. The method was readily adapted for the rapid synthesis of coveted 1,4-benzodiazepine-3,5-diones.Non-fullerene acceptors, especially acceptor-donor-acceptor structured fused-ring electron acceptors (FREAs), have attracted widespread attention in organic solar cells because of their versatile molecular design in fine-tuning light absorption and energy levels. We report the accuracy of Time-Dependent Density Functional Theory (TD-DFT) for FREAs by comparing their theoretically predicted vertical absorption wavelength (λver-abso) with the experimental maximum absorption (λmax). The λver-abso values of 50 molecules obtained from major types of FREAs have been investigated using TD-DFT by considering the solvent effects. Adavosertib The values of λver-abso predicted with a pure density functional (PBE), global hybrids (B3LYP and PBE0) and range-separated schemes (CAM-B3LYP and LC-ωPBE) follow the exact exchange percentage included at an intermediate inter-electronic distance. Global hybrids outperform all other schemes. The mean absolute error provided is 22 nm by PBE0 and 38 nm by B3LYP for the whole set of molecules. The maximum deviation of 92 nm provided by B3LYP and 69 nm provided by PBE0 confirms that PBE0 is more appropriate for predicting the absorption wavelengths when designing new FREAs. By applying linear regression analysis to obtain the calibration curve, we found that the range-separated methods provide an equal or even more consistent description of FREA excited states. For the whole set of molecules, linearly corrected data yield an average error of 25 and 27 nm for CAM-B3LYP and LC-ωPBE, respectively. Consequently, when a statistical analysis technique is applicable for a certain series of FREAs, a theoretical method permits a chemically comprehensive and empirically good explanation of UV/Vis spectra for newly-designed FREAs.
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