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Ultracold chemical reactions of weakly bound triplet-state alkali-metal dimer molecules have recently attracted much experimental interest. We perform rigorous quantum scattering calculations with a new $ab\, initio$ potential energy surface to explore the chemical reaction of spin-polarized NaLi($a^3\Sigma^+$) and Li($^2$S) to form Li$_2$($a^3\Sigma_u^+$) and Na($^2$S). The reaction is exothermic, and proceeds readily at ultralow temperatures. Significantly, we observe strong sensitivity of the total reaction rate to small variations of the three-body part of the Li$_2$Na interaction at short range, which we attribute to a relatively small number of open Li$_2$($a^3\Sigma_u^+$) product channels populated in the reaction. This provides the first signature of highly non-universal dynamics seen in rigorous quantum reactive scattering calculations of an ultracold exothermic insertion reaction involving a polar alkali-dimer molecule, opening up the possibility of probing microscopic interactions in atom+molecule collision complexes via ultracold reactive scattering experiments., Comment: 26 pages, 5 figures (Supporting information: 12 pages, 5 figures)

Despite intensive studies for decades on synaptic integration in the somatodendritic compartments, its spatio-temporal dynamics remains obscure because of the technical limitation to obtain local potentials at multiple subcellular regions. To address this issue, here we used a genetically-encoded voltage indicator together with local uncaging of glutamate or GABA on cultured hippocampal pyramidal neurons. Fluorescence voltage imaging revealed direction-dependent opposite changes of excitatory postsynaptic potentials (EPSPs) in a dendrite: EPSPs attenuated during propagation toward the soma whereas amplified toward the distal branch end. The direction-dependent local augmentation of EPSPs was mediated by the TTX-resistant Na+ channels and KCC2-dependent deeper dendritic resting potential than in soma, the latter of which was directly unveiled by subcellular patch-clamp recordings from a thin dendrite hundreds um away from the soma. Taken all these results together, our data identifies an asymmetric modulation of excitatory signals in neuronal dendrites, potentially impacting local integration in a branch.

Background: Allergic bronchopulmonary mycosis (ABPM) occurs with fungi, other than Aspergillus fumigatus. However, the clinical characteristics of ABPM caused by non-Aspergillus species are unspecified. Methods: We retrospectively reviewed all patients with ABPM who visited to our hospital between April 2005 and December 2020. The causative fungi and clinical characteristics were analyzed. Patients were divided into the Aspergillus group and the non-Aspergillus group. Results: Fourteen patients and five patients were included in the Aspergillus group and the non-Aspergillus group, respectively. Compared to the Aspergillus group, the non-Aspergillus group had a significantly low serum immunoglobulin E level and low forced vital capacity. In addition, the non-Aspergillus group had a lower rate of the requirement for oral corticosteroid treatment and a low frequency of recurrence. Conclusion: Patients with non-Aspergillus ABPM had lower type 2 inflammation than did patients with allergic bronchopulmonary aspergillosis.

BACKGROUND: Tumor necrosis factor (TNF)-α, a proinflammatory cytokine, is involved in the pathogenesis of rheumatoid arthritis (RA). The omega-3 unsaturated fatty acid-derived metabolites resolvin (Rv) D1, RvE1, and maresin-1 (MaR1) have been reported as anti-inflammatory lipid mediators and are known as specialized pro-resolving mediators (SPMs). In this study, we aimed to investigate the anti-inflammatory effects of SPMs on TNF-α-induced responses in synovial fibroblasts. METHODS: We investigated the effects of SPMs on gene expression and/or production of cyclooxygenase-2 (COX-2), microsomal prostaglandin E synthase-1 (mPGES-1), interleukin (IL)-6, and matrix metalloproteinase (MMP)-3, which are involved in TNF-α-induced synovitis in RA or OA synovial fibroblasts, by quantitative real-time PCR. We also investigated the effects of SPMs on the mitogen-activated protein kinase (MAPK) signaling pathway by western blotting. Anti-inflammatory effects of SPMs were evaluated by applying SPMs to cultured synovial fibroblasts, followed by TNF-α stimulation. RESULTS: The induction of COX-2, mPGES-1, IL-6, and MMP-3 by TNF-α in synovial fibroblasts was not suppressed by omega 3-derived SPMs regardless of their origin such as RA or OA. SPMs had no effect on lipid mediator receptor gene expression induce by TNF-α and did not inhibit the TNF-α-activated MAPK signaling pathway. The production of COX-2 and IL-6 protein was significantly decreased by p38 inhibitor. CONCLUSION: Despite reports on the anti-inflammatory effect of omega 3-derived SPMs, its anti-inflammatory effect on TNF-α-induced responses was not observed in synovial fibroblasts. The reason may be that SPMs have no suppressive effect on p38 activation, which plays an important role in the production of inflammatory cytokines in synovial fibroblasts.

Modification of the halogen constituent in the fluorinated tolane moiety is an effective method for tailoring the functionality of the material.

A novel π-conjugated tricarbocycle with a CF2CF2-containing cyclohexa-1,3-diene skeleton was revealed to show aggregation-induced enhancement emission, which would pave the way for novel solid-state fluorescence materials.

Ph2N-Substituted fluorinated tolanes produced two polymorphisms, which display a distinct photoluminescence behavior; one polymorphism showed green PL and the other exhibited yellow PL.

Precise molecular design of fluorinated tolane-based fluorophores can control both the electron density and molecular aggregated structures.

The calcium monofluoride (CaF) molecule has emerged as a promising candidate for precision measurements, quantum simulation, and ultracold chemistry experiments. Inelastic and reactive collisions of laser cooled CaF molecules in optical tweezers have recently been reported and collisions of cold Li atoms with CaF are of current experimental interest. In this paper, we report ab initio electronic structure and full-dimensional quantum dynamical calculations of the Li + CaF $\to$ LiF + Ca chemical reaction. The electronic structure calculations are performed using the internally contracted multi-reference configuration-interaction method with Davidson correction (MRCI+Q). An analytic fit of the interaction energies is obtained using a many-body expansion method. A coupled-channel quantum reactive scattering approach implemented in hyperspherical coordinates is adopted for the scattering calculations under cold conditions. Results show that the Li + CaF reaction populates several low-lying vibrational levels and many rotational levels of the product LiF molecule and that the reaction is inefficient in the 1-100 mK regime allowing sympathetic cooling of CaF by collisions with cold Li atoms.

In recent experiments using the Stark-induced adiabatic Raman passage technique, Zhou et al. (

In recent experiments using the Stark-induced Adiabatic Raman Passage (SARP) technique, Zhou et al. measured the product's angular distribution for the collisions between He and aligned D2 molecules at cold collision energies. The signatures of the angular distributions were attributed to a l=2 resonance that governs scattering at low energies. A first principles quantum mechanical treatment of this problem is presented here using a highly accurate interaction potential for the He-H2 system. Instead, our results predict a very intense l=1 resonance at low energies, leading to angular distributions that differ from those measured in the experiment. A good agreement with the experiment is achieved only when the l=1 resonance is artificially removed, for example, by excluding the lowest energies present in the experimental velocity distribution. Our analysis revealed that neither the position nor the intensity of the l=1 resonance significantly changes when the interaction potential is modified within its predicted uncertainties. Energy-resolved measurements may help to resolve the discrepancy.

Ion sputtering, whereby atoms on target surfaces are bombarded by energetic ions, is a key process in the film-coating industry. However, its detailed mechanism has not yet been clarified and remains an empirical operation. This article demonstrates that the redeposition of metal on the target surface significantly enhances the sputtering rate. Although the effect differs depending on the metal species, significant enhancement in the sputtering rate occurs in glow-discharge plasma sputtering––a maximum increase of approximately 2.4 times was observed under experimental conditions. The experimental data agree well with the model equation, which superimposes two processes: sputtering by the desorbed redeposited metal and reduction of the enthalpy of sublimation by the adsorbed redeposited metal. The results of this study demonstrate that the metal redeposition effect is a key mechanism missing in the plasma sputtering process and that taking redeposition into account frees us from its empirical use. These findings are expected to address several of the existing questions related to sputtering, enabling the development of a wide variety of applications.

Dual-state emissive (DSE) luminophores, which can luminesce both in solution and in solid states, have recently attracted significant attention because of their broad applications. However, their development is difficult due to the difference in molecular design between solution- and solid-state luminophores. In this study, DSE luminophores based on unsymmetrical hexafluorocyclopentene-linked twisted π-conjugated structures carrying various substituents to tune the electron-density were designed and synthesized in a single-step reaction from heptafluorocyclopentene or perfluoro-1,2-diphenylcyclopentene derivatives. The twisted π-conjugated luminophores exhibited absorption in the UV region at approximately 330 nm, along with several signals in the high-energy region. Upon irradiating the luminophore solution (wavelength 330 nm), light-green to yellow photoluminescence (PL) was observed in the range of 422–471 nm with high PL efficiency. Theoretical calculations revealed that excitation from ground to excited states altered the structural shape of the luminophores from twisted to planar, leading to red-shifted PL and high PL efficiency (ΦPL). The intense blue PL exhibited by the luminophores in the crystalline state was attributed to their twisted molecular structures that suppressed non-radiative deactivation via the effective blocking of π/π stacking interactions.

The performance of semiconductor devices has been improved by the miniaturization and the adoption of various materials. Together with this improvement, it has become difficult to measure the amount of injected impurities to control the electrical conductivity under the three-dimensional microstructure. As the volume decreases, the lower limit of the concentration that can be defined increases. In a 10-nm cubic region of silicon, there are approximately 64 000 atoms. One atom is approximately 16 ppm, and concentrations below that level cannot be defined. The limitation on the measurement accuracy of the PN junction position becomes unclear. Generally, the electrical characteristics of a semiconductor device are determined by the position of the PN junction and the concentrations in the P and N regions. In this paper, we elucidate the interface state of a minute PN junction. Based on the above, we will examine the lowest extent to which the concentration of impurities can be measured in a microvolume, with the current physical analysis technology, assuming ideal measurement conditions without any disturbance. Finally, we measure the sensitivity improvement of mass spectrometry using postionization technology with a femtosecond pulse infrared laser and demonstrate that it is possible to improve the performance of the impurity measurement.