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The acidic environment within lysosomes is maintained within a narrow pH range (pH 4.5-5.0) optimal for digesting autophagic cargo macromolecules so that the resulting building block metabolites can be reused. This pH homeostasis is a consequence of proton influx produced by a V-type H

We study the nonlinear limits to arbitrage in a model. When mispricing is small, arbitrage activity increases with mispricing because of the higher cost‐adjusted return. However, at high levels of mispricing, arbitrageurs are deterred by larger mispricing as funding constraints become more binding. Testing the model predictions on the index spot‐futures arbitrage with a Markov‐switching model, we document an inverse U‐shaped relationship between mispricing and arbitrage activity. The extreme regime is with the largest mispricing but least arbitrage activity, and coincides with the market turmoil, suggesting that funding constraints become the main driver behind the limit to arbitrage.

This pilot clinical trial investigated solution-focused brief therapy (SFBT) for psychological distress among adolescent and young adult (AYA) patients with cancer in China.Fifty Chinese AYA patients diagnosed with cancer were randomized into the treatment group (SFBT) and control group (active control). Psychological distress was measured by the brief symptom inventory and hope was measured by the Herth-Hope-Index. Treatment effects were analyzed using analysis-of-covariance and between-group small-sample-size corrected Hedges'The results indicated that SFBT resulted in a significant reduction in the psychological distress and improvement in hope of AYA patients with cancer. Analyses of the 4-week posttreatment score suggest the short-term sustainability of SFBT for psychological distress among AYAs diagnosed with cancer.This study has demonstrated that SFBT's impact is statistically significant and clinically meaningful. The inclusion of positive emotions, i.e., hope, as part of the investigation also highlighted the significance of promoting positive emotions among AYA patients with cancer.

The first direct aziridination of triaryl-substituted alkenes was achieved by means of an electrochemical process that could extend to multisubstituted styrenes. Specifically, hexafluoroisopropanol sulfamate was used as a nucleophilic nitrogen source. Mechanistic experiments suggest that this electrochemical process proceeds by stepwise formation of two C-N bonds through reactions between cationic carbon species and the sulfamate.

The difluoropropargyl group is a useful moiety for biological applications such as in vivo click chemistry for molecular imaging techniques. Silyl-protected bromodifluoropropyne is an important difluoropropargylation reagent with previously unexplored radical reactivity. Herein, we report visible-light-induced thiyl-radical-catalyzed hydrodifluoropropargylation reactions between silyl-protected bromodifluoropropyne and alkenes in the presence of benzothiazoline as a critical reductant.

A subphthalocyanine-dithienylethene dyad has been synthesized and characterized by 1H-, [Formula: see text]C-NMR, HR-MS, UV-visible and emission spectroscopy. The results show that photoinduced isomerization of dithienylethene moiety from close-form to opened form can be achieved under visible light using subphthalocyanine as a light-harvesting unit and the fluorescence properties of subphthalocyanine could be modulated by the isomerization state of the dithienylethene moiety.

The formation of a viral particle generally involves hundreds of proteins, making the assembly process intricate. Despite its intrinsic complexity, the production of a viral particle begins through the interaction between the basic assembly components. For the cowpea chlorotic mottle virus (CCMV), the first steps of the assembly process involve dimers of the capsid protein. Here, we carried out atomistic molecular dynamics simulations to investigate the initial assembly process of CCMV to get insight into the interactions at the molecular level. We found that salinity not only affects the electrostatic interactions between dimers but also changes the conformation of the positively charged N-terminal tails and can cause a serious steric hindrance for other dimers binding to the hydrophobic domains. An RNA rod was used to mimic a long segment of a viral genome and to study its interaction with dimers. We observed that the dimer with tails prefers to bind on the RNA rod with its positively charged inner side. The dimer-RNA interaction was found to be as strong as the dimer-dimer interaction, whereas the association energies between a dimer and a pentamer or a hexamer of dimers were high but strongly depended on the presence of the tails. Upon heating, the capsid experienced a shrinkage accompanied by a loss of order in the icosahedral crystal structure.

A series of azulene-functionalized BODIPY derivatives have been synthesized via a Suzuki–Miyaura cross-coupling reaction. The introduction of 2-azulenyl moieties onto the BODIPY core results in more red-shifted absorption bands than those observed for 1-azulenyl functionalization. Upon protonation by TFA, a blue shift of the main absorption band of the 2-azulenyl-substituted compounds is observed along with a decrease in intensity, and a new weaker peak is observed at long wavelength. In contrast, the absorption of the 1-azulenyl-substituted compounds is almost unchanged upon protonation.

Visible-light-induced catalytic hydrophosphonodifluoromethylation of mono- and disubstituted alkenes using bromodifluoromethanephosphonate with a Hantzsch ester as the terminal reductant is reported. The combination of thiyl-radical catalysis with photoredox catalysis is important for achieving good chemoselectivity and high yields.

Cholesteric liquid crystals (CLCs) exhibit selective Bragg reflections of circularly polarized (CP) light owing to their spontaneous self-assembly abilities into periodic helical structures. Photonic cross-communication patterns could be generated toward potential security applications by spherical cholesteric liquid crystal (CLC) structures. To endow these optical patterns with tunability, we fabricated spherical CLC Bragg reflectors in the shape of microshells by glass-capillary microfluidics. Water-soluble magnetofluid with Fe3O4 nanoparticles incorporated in the inner aqueous core of CLC shells is responsible for the non-invasive transportable capability. With the aid of an external magnetic field, the reflection interactions between neighboring microshells and microdroplets were identified by varying the mutual distance in a group of magnetically transportable and unmovable spherical CLC structures. The temperature-dependent optical reflection patterns were investigated in close-packed hexagonal arrangements of seven CLC microdroplets and microshells with inverse helicity handedness. Moreover, we demonstrated that the magnetic field-assisted assembly of microshells array into geometric figures of uppercase English letters “L” and “C” was successfully achieved. We hope that these findings can provide good application prospects for security pattern designs.

The dissociation of icosahedral viral capsids was investigated by a homogeneous and a heterogeneous lattice model. In thermal dissociation experiments with cowpea chlorotic mottle virus and probed by small-angle neutron scattering, we observed a slight shrinkage of viral capsids, which can be related to the strengthening of the hydrophobic interaction between subunits at increasing temperature. By considering the temperature dependence of hydrophobic interaction in the homogeneous lattice model, we were able to give a better estimate of the effective charge. In the heterogeneous lattice model, two sets of lattice sites represented different capsid subunits with asymmetric interaction strengths. In that case, the dissociation of capsids was found to shift from a sharp one-step transition to a gradual two-step transition by weakening the hydrophobic interaction between AB and CC subunits. We anticipate that such lattice models will shed further light on the statistical mechanics underlying virus assembly and disassembly.

A virus is made up of a protein shell, the $c\phantom{\rule{0}{0ex}}a\phantom{\rule{0}{0ex}}p\phantom{\rule{0}{0ex}}s\phantom{\rule{0}{0ex}}i\phantom{\rule{0}{0ex}}d$, protecting its genetic material, and that's all. The subunits of the shell are arranged in a two-dimensional structure, held in place by a fine interplay between short-range and electrostatic interactions. The authors show that thermal dissociation of the capsid proceeds through a two-dimensional phase transition, providing direct quantitative insight into the strengths of the interactions and their variations in different ionic environments.

We report the first example of difluoroalkylation/C–H annulation cascade reactions of cyclopropyl olefins induced by visible-light photoredox catalysis regioselectively affording partially hydrogenated naphthalenes and quinolines with a variety of difluorinated side chains. The alkylation reagent could be extended to monofluoro and trifluoro reagents, nitrile and malonate. The regioselectivity was investigated by means of density functional theory calculations.

Six samples of the Linglong granitic pluton from the southeastern margin of the North China craton yield similar Jurassic magmatic zircon U–Pb ages and evolved whole-rock Sr–Nd isotopic compositions. They are weakly peraluminous to strongly peraluminous, with A/CNK (molar Al2O3/[CaO + Na2O + K2O]) ratios of 1.05 to 1.3 except one sample with an A/CNK of 0.98. However, they have contrasting inherited zircon ages and magmatic zircon Hf and O isotopic compositions. Two samples have ~ 2.5 Ga inherited zircons and high δ18O magmatic zircons and are interpreted to be derived dominantly from the lower crust of the North China craton. Another two samples with dominantly Triassic inherited zircons and low δ18O magmatic zircons are considered to be derived mainly from the subducted continental crust of the South China craton and the source was considered to be significantly depleted in 18O during Triassic metamorphism. The rest two samples have dominantly Neoproterozoic inherited zircons and intermediate δ18O magmatic zircons and are also considered to be derived mainly from the subducted continental crust of the South China craton. But the source was not significantly depleted in 18O during Triassic metamorphism. The different lithologies, whole-rock eNd(t) and zircon eHf(t) between the samples also strongly support that they are derived from different sources. Although magmatic zircons from the six samples have variable δ18O from 0.7 to 8.5‰ and eHf(t) from − 27.6 to − 11.8, individual samples have more limited eHf(t) and δ18O. The δ18O and eHf(t) of magmatic zircons from the samples indicate no contribution of mantle- derived magmas to the Linglong granites. This is supported by the fact of no coeval mantle-derived rocks in the region. The results suggest that large variations of eHf(t) and δ18O do not necessarily indicate mixing between mantle- and crustal-derived magmas. Instead, they may reflect heterogeneity in the source. The granites are interpreted to result from partial melting of the thickened crust caused by Triassic subduction of the South China craton continental crust beneath the North China craton. Subsequent lithospheric extension and orogenic collapse are the most likely mechanism for the granites.