Broad Impacts of Coronavirus Disease 2019 (COVID-19) Pandemic on Acute Respiratory Infections in China: An Observational Study.

Background: To combat the coronavirus disease 2019 (COVID-19) pandemic, nonpharmaceutical interventions (NPIs) were implemented worldwide, which impacted a broad spectrum of acute respiratory infections (ARIs).

Methods: Etiologically diagnostic data from 142 559 cases with ARIs, who were tested for 8 viral pathogens (influenza virus [IFV], respiratory syncytial virus [RSV], human parainfluenza virus [HPIV], human adenovirus [HAdV], human metapneumovirus [HMPV], human coronavirus [HCoV], human bocavirus [HBoV], and human rhinovirus [HRV]) between 2012 and 2021, were analyzed to assess the changes in respiratory infections in China during the first COVID-19 pandemic year compared with pre-pandemic years.

Results: Test-positive rates of all respiratory viruses decreased during 2020, compared to the average levels during 2012-2019, with changes ranging from -17.

Extremely solvent-enhanced absorbance and fluorescence of carbazole interpreted using a damped Franck-Condon simulation.

Extremely solvent-enhanced absorption and fluorescence spectra of carbazole were investigated by performing a generalized multi-set damped Franck-Condon spectral simulation. Experimental absorption and fluorescence spectra of carbazole in the gas phase were first well reproduced by performing an un-damped Franck-Condon simulation, but a one-set scaling damped Franck-Condon simulation severely underestimated the intensities of the peaks of experimental absorption and fluorescence spectra of carbazole in n-hexane. Then, a multi-set scaling damped Franck-Condon simulation was proposed and carried out for simulating the extremely solvent-enhanced absorbance and fluorescence, and here, the simulated spectra agreed well with the experimental ones.

Dynamic Stark-Induced Coherent π-Electron Rotations in a Chiral Aromatic Ring Molecule: Application to Phenylalanine.

We present the results of a theoretical study on dynamic Stark-induced coherent π-electron rotations in a chiral aromatic ring molecule. This is an extension of our previous papers, which have been published in Mineo , H. [ 2016 , 18 , 26786 - 26795 ] and Mineo , H.

First-principles study on sum-frequency generation spectroscopy of methanol adsorbed on TiO(110) surface: Effects of substrate and molecular coverages.

In this work, starting from the general theory of sum-frequency generation (SFG), we proposed a computational strategy utilizing density functional theory with periodic boundary conditions to simulate the vibrational SFG of molecules/solid surface adsorption system. The method has been applied to the CHOH/TiO(110) system successfully. Compared with the isolated molecule model, our theoretical calculations showed that the TiO substrate can significantly alter the second-order susceptibilities of a methanol molecule which is directly related to the SFG intensity.

Quantum Design for Ultrafast Probing of Molecular Chirality through Enantiomer-Specific Coherent π-Electron Angular Momentum.

Probing molecular chirality, right-handed or left-handed chiral molecules, is one of the central issues in chemistry and biochemistry. The conventional theory of optical activity measurements such as circular dichroism has been derived in the second-order processes involving electric and magnetic dipole moments, and the signals are very weak. We propose an efficient enantiomer-probing scenario for chiral aromatic ring molecules based on photoinduced coherent π-electron rotations.

Directed motion from particle size oscillations inside an asymmetric channel.

The motion of a spherical Brownian particle in an asymmetric periodic channel is considered. Under an external periodic stimulus, the particle switches between two states with different particle radius, every half-period. Using Brownian dynamics simulations, we show that the particle size oscillation, combined with the asymmetry of the channel, induces a drift along the channel axis, directed towards the steeper wall of the channel.

High-temperature ratchets with sawtooth potentials.

The concept of the effective potential is suggested as an efficient instrument to get a uniform analytical description of stochastic high-temperature on-off flashing and rocking ratchets. The analytical representation for the average particle velocity, obtained within this technique, allows description of ratchets with sharp potentials (and potentials with jumps in particular). For sawtooth potentials, the explicit analytical expressions for the average velocity of on-off flashing and rocking ratchets valid for arbitrary frequencies of potential energy fluctuations are derived; the difference in their high-frequency asymptotics is explored for the smooth and cusped profiles, and profiles with jumps.

Induction of unidirectional π-electron rotations in low-symmetry aromatic ring molecules using two linearly polarized stationary lasers.

A new laser-control scenario of unidirectional π-electron rotations in a low-symmetry aromatic ring molecule having no degenerate excited states is proposed. This scenario is based on dynamic Stark shifts of two relevant excited states using two linearly polarized stationary lasers. Each laser is set to selectively interact with one of the two electronic states, the lower and higher excited states are shifted up and down with the same rate, respectively, and the two excited states become degenerate at their midpoint.

Theoretical investigations of absorption and fluorescence spectra of protonated pyrene.

The equilibrium geometry and 75 vibrational normal-mode frequencies of the ground and first excited states of protonated pyrene isomers were calculated and characterized in the adiabatic representation by using the complete active space self-consistent field (CASSCF) method. Electronic absorption spectra of solid neon matrixes in the wavelength range 495-415 nm were determined by Maier et al. and they were analyzed using time-dependent density functional theory calculations (TDDFT).

Excited-state localization and energy transfer in pyrene core dendrimers with fluorene/carbazole as the dendrons and acetylene as the linkages.

A multi-leveled theoretical investigation combining TD-DFT (B3LYP and CAM-B3LYP) methods and a semi-empirical method was conducted to determine the structure-related spectral properties of T-series dendrimers composed of nearly hundreds of atoms, based on a proposed molecular model. Both one- and two-photon absorption spectra of the dendrimer molecules were well reproduced. The "antenna effect" in the dendrimers molecule was theoretically studied.

Diffusion of a massive particle in a periodic potential: Application to adiabatic ratchets.

We generalize a theory of diffusion of a massive particle by the way in which transport characteristics are described by analytical expressions that formally coincide with those for the overdamped massless case but contain a factor comprising the particle mass which can be calculated in terms of Risken's matrix continued fraction method (MCFM). Using this generalization, we aim to elucidate how large gradients of a periodic potential affect the current in a tilted periodic potential and the average current of adiabatically driven on-off flashing ratchets. For this reason, we perform calculations for a sawtooth potential of the period L with an arbitrary sawtooth length (l View Article and Find Full Text PDF

The generation of stationary π-electron rotations in chiral aromatic ring molecules possessing non-degenerate excited states.

The electron angular momentum is a fundamental quantity of high-symmetry aromatic ring molecules and finds many applications in chemistry such as molecular spectroscopy. The stationary angular momentum or unidirectional rotation of π electrons is generated by the excitation of a degenerated electronic excited state by a circularly-polarized photon. For low-symmetry aromatic ring molecules having non-degenerate states, such as chiral aromatic ring molecules, on the other hand, whether stationary angular momentum can be generated or not is uncertain and has not been clarified so far.

Theory of Triplet Excitation Transfer in the Donor-Oxygen-Acceptor System: Application to Cytochrome b6f.

Theoretical consideration is presented of the triplet excitation dynamics in donor-acceptor systems in conditions where the transfer is mediated by an oxygen molecule. It is demonstrated that oxygen may be involved in both real and virtual intramolecular triplet-singlet conversions in the course of the process under consideration. Expressions describing a superexchange donor-acceptor coupling owing to a participation of the bridging twofold degenerate oxygen's virtual singlet state are derived and the transfer kinetics including the sequential (hopping) and coherent (distant) routes are analyzed.

Theoretical studies on the absorption spectra of cis-[Ru(4,4'-COO-2,2'-bpy)2(X)2](4-), (X = NCS, Cl) and panchromatic trans-terpyridyl Ru complexes including strong spin-orbit coupling.

In this paper, we theoretically and experimentally investigate the photophysical and chemical characteristics and absorption spectra of various ruthenium complexes in solution used as efficient dye-sensitized solar cells. The target molecules are two well-known complexes, cis-[Ru(4,4'-COO-2,2'-bpy)2(X)2](4-), (X = NCS, Cl) and trans-terpyridyl Ru. The experimental absorption spectra of these molecules, which show strong spin-orbit (SO) coupling, are simulated using first-order perturbation theory based on time-dependent density functional theory and quantum chemistry calculations.

Pressure-enhanced surface interactions between nano-TiO₂ and ionic liquid mixtures probed by high pressure IR spectroscopy.

The pressure-dependent interactions between the ionic liquid mixture ([MPI][I1.5]) and nano-TiO2 surfaces have been studied up to 2.5 GPa.

Inertial effects in adiabatically driven flashing ratchets.

We study analytically the effect of a small inertial correction on the properties of adiabatically driven flashing ratchets. Parrondo's lemma [J. M.

Induction of indoleamine 2,3-dioxygenase (IDO) enzymatic activity contributes to interferon-gamma induced apoptosis and death receptor 5 expression in human non-small cell lung cancer cells.

Interferon-gamma (IFN-γ) has been used to treat various malignant tumors. However, the molecular mechanisms underlying the direct anti-proliferative activity of IFN-γ are poorly understood. In the present study, we examined the in vitro antitumor activity of IFN-γ on two human non-small-cell lung carcinoma (NSCLC) cell lines, H322M and H226.

Landscapes of four-enantiomer conical intersections for photoisomerization of stilbene: CASSCF calculation.

The photoisomerization of cis- and trans-stilbene through conical intersections (CI) is mainly governed by four dihedral angles around central C═C double bonds. The two of them are C-C═C-C and H-C═C-H dihedral angles that are found to form a mirror rotation coordinate, and the mirror plane appears at the two dihedral angles equal to zeros with which the middle state is defined through partial optimization. There exist the first-type of hula-twist-CI enantiomers, the second-type of hula-twist-CI enantiomers, the first-type of one-bond-flip-CI enantiomers, and the second type of one-bond-flip-CI enantiomers as well as cis-enantiomers and trans-enantiomers with respect to this mirror plane.

Contribution of thermal energy to initial ion production in matrix-assisted laser desorption/ionization observed with 2,4,6-trihydroxyacetophenone.

Rationale: Although several reaction models have been proposed in the literature to explain matrix-assisted laser desorption/ionization (MALDI), further study is still necessary to explore the important ionization pathways that occur under the high-temperature environment of MALDI. 2,4,6-Trihydroxyacetophenone (THAP) is an ideal compound for evaluating the contribution of thermal energy to an initial reaction with minimum side reactions.

Methods: Desorbed neutral THAP and ions were measured using a crossed-molecular beam machine and commercial MALDI-TOF instrument, respectively.

Tazarotene induces apoptosis in human basal cell carcinoma via activation of caspase-8/t-Bid and the reactive oxygen species-dependent mitochondrial pathway.

Previous studies suggest that tazarotene, a new member of the acetylenic class of RARβ/γ selective retinoids which is approved to treat a variety of skin diseases, exhibits an anti-proliferative effect in human basal cell carcinoma (BCC) by triggering caspase-dependent apoptosis. However, the detailed molecular mechanisms underlying the anti-tumor activity of tazarotene are poorly understood. This study aims at investigating the molecular mechanisms of tazarotene-induced apoptosis in human BCC cells.

Fluctuation-induced transport of two coupled particles: effect of the interparticle interaction.

We consider a system of two coupled particles fluctuating between two states, with different interparticle interaction potentials and particle friction coefficients. An external action drives the interstate transitions that induces reciprocating motion along the internal coordinate x (the interparticle distance). The system moves unidirectionally due to rectification of the internal motion by asymmetric friction fluctuations and thus operates as a dimeric motor that converts input energy into net movement.

Quantum Localization of Coherent π-Electron Angular Momentum in (P)-2,2'-Biphenol.

Controlling π-electrons with delocalized character is one of the fundamental issues in femtosecond and attosecond chemistry. Localization of π-electron rotation by using laser pulses is expected to play an essential role in nanoscience. The π-electron rotation created at a selected aromatic ring of a single molecule induces a local intense electromagnetic field, which is a new type of ultrafast optical control functioning.

Topology of conical/surface intersections among five low-lying electronic states of CO2: multireference configuration interaction calculations.

Multi-reference configuration interaction with single and double excitation method has been utilized to calculate the potential energy surfaces of the five low-lying electronic states (1)A1, (1)A2, (3)A2, (1)B2, and (3)B2 of carbon dioxide molecule. Topology of intersections among these five states has been fully analyzed and is associated with double-well potential energy structure for every electronic state. The analytical potential energy surfaces based on the reproducing kernel Hilbert space method have been utilized for illustrating topology of surface crossings.

Adiabatically driven Brownian pumps.

We investigate a Brownian pump which, being powered by a flashing ratchet mechanism, produces net particle transport through a membrane. The extension of the Parrondo's approach developed for reversible Brownian motors [Parrondo, Phys. Rev.

Specific interactions between the quaternary ammonium oligoether-based ionic liquid and water as a function of pressure.

The interactions between Ammoeng 100 and water are probed using high-pressure infrared measurements and DFT-calculations. The results of infrared absorption profiles suggest that the energetically favored approach for water molecules to interact with Ammoeng 100 is via the formation of anion-water interactions, whereas the alkyl C-H groups play much less important roles. After comparison with pure Ammoeng 100, it appears that no appreciable changes in band frequencies of alkyl C-H vibrations occurred as Ammoeng 100 was mixed with D2O.