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Anion chemical dynamics of autodetachment and fragmentation mediated by the dipole-bound state (DBS) have been thoroughly investigated in a state-specific way by employing the picosecond time-resolved or the nanosecond frequency-resolved spectroscopy combined with the cryogenically cooled ion trap and velocity-map imaging techniques. For the

Korean red ginseng has been widely used as an herbal medicine. Red ginseng dietary fiber (RGDF) is a residue of the processed ginseng product but still contains bioactive constituents that can be applied as prebiotics. In this study, we evaluated changes on fermentation profiles and probiotic properties of strains that belong to family Lactobacillaceae with RGDF supplementation. Metabolomic analyses were performed to understand specific mechanisms on the metabolic alteration by RGDF and to discover novel bioactive compounds secreted by the RGDF-supplemented probiotic strain. RGDF supplementation promoted short-chain fatty acid (SCFA) production, carbon source utilization, and gut epithelial adhesion of Lactiplantibacillus plantarum and inhibited attachment of enteropathogens. Intracellular and extracellular metabolome analyses revealed that RGDF induced metabolic alteration, especially associated with central carbon metabolism, and produced RGDF-specific metabolites secreted by L. plantarum, respectively. Specifically, L. plantarum showed decreases in intracellular metabolites of oleic acid, nicotinic acid, uracil, and glyceric acid, while extracellular secretion of several metabolites including oleic acid, 2-hydroxybutanoic acid, hexanol, and butyl acetate increased. RGDF supplementation had distinct effects on L. plantarum metabolism compared with fructooligosaccharide supplementation. These findings present potential applications of RGDF as prebiotics and bioactive compounds produced by RGDF-supplemented L. plantarum as novel postbiotic metabolites for human disease prevention and treatment.

Infinitely thin multiple strip scattering problems are studied using the sub-domain approach for two-dimensional transverse magnetic (TM) and transverse electric (TE) excitations. The sub-domain approach divides the entire domain into several partially overlapping sub-domains, within which fields are expanded by classical techniques. The mode matching method is used to impose continuity conditions. Results are validated by comparing to numerical results from COMSOL. Results show that the sub-domain approach can be as accurate as the numerical solutions and may offer substantial improvements in efficiency.

ConspectusNonvalence bound states (NBS) are anionic states where the excess electron is extremely loosely bound to the neutral core through long-range potentials. In contrast to the valence orbitals of which the electron occupancy determines the molecular structure, as well as the chemical reactivity, the nonvalence orbital is quite diffuse and located far from the neutral core. The NBS can be classified into the dipole-bound state (DBS), quadruple-bound state (QBS), or correlation-bound state (CBS) according to the nature of the electron-neutral interaction, although their interaction potentials may cooperatively contribute. The NBS is ubiquitous in nature and has the strong implications in atmospheric, interstellar, or biological chemistry. Accordingly, NBS has long been conceived to play the role of the doorway into the formation of a stable anion or dissociative electron attachment (DEA). Despite intensive and extensive studies, however, the quantum-mechanical nature of NBS is still far from being thorough understanding. Herein, we describe a new aspect of state-specific NBS-mediated chemical dynamics, which has been revealed through a series of recent studies by our group. We have employed picosecond time-resolved pump-probe spectroscopy combined with cryogenically cooled ion trap and velocity-map imaging techniques to study closed-shell anions generated by electrospray ionization. DBS vibrational Feshbach resonances are prepared by the optical excitation of phenoxide, for instance, and their individual lifetimes have been precisely measured in a state-specific manner to reveal the strong mode-dependency of the autodetachment rate. Fermi's golden rule turns out to be extremely useful for a rational explanation of the experiment, although the more sophisticated theoretical model is desirable for the more quantitative analysis. For the DBS of

The S1-state decaying rates of the three different benzenediols, catechol, resorcinol, and hydroquinone, and their 1:1 water clusters have been state-specifically measured using the picosecond time-resolved parent ion transients obtained by the pump (excitation) and probe (ionization) scheme. The S1 lifetime of catechol is found to be short, giving τ ∼ 5.9 ps at the zero-point level. This is ascribed to the H-atom detachment from the free OH moiety of the molecule. Consistent with a previous report (J. Phys. Chem. Lett.2013, 4, 3819-3823), the S1 lifetime gets lengthened with low-frequency vibrational mode excitations, giving τ ∼ 9.0 ps for the 116 cm-1 band. The S1 lifetimes at the additional vibronic modes of catechol are newly measured, showing the nonnegligible mode-dependent fluctuations of the tunneling rate. When catechol is complexed with water, the S1 lifetime is enormously increased to τ ∼ 1.80 ns at the zero-point level while it shows an unusual dip at the intermolecular stretching mode excitation (τ ∼ 1.03 ns at 146 cm-1). Otherwise, it is shortened monotonically with increasing the internal energy, giving τ ∼ 0.67 ns for the 856 cm-1 band. Two different asymmetric or symmetric conformers of resorcinol give the respective S1 lifetimes of 4.5 or 6.3 ns at their zero-point levels according to the estimation from our transients taken within the temporal window of 0-2.7 ns. When resorcinol is 1:1 complexed with H2O, the S1 decaying rate is slightly accelerated for both conformers. The S1 lifetimes of trans and cis forms of hydroquinone are measured to be more or less same, giving τ ∼ 2.8 ns at the zero-point level. When H2O is complexed with hydroquinone, the S1 decaying process is facilitated for both conformers, slightly more efficiently for the cis conformer.

Perfect electric conducting (PEC) sectors illuminated by transverse magnetic (TM) and transverse electric (TE) field excitations are studied using the subdomain approach. The subdomain approach, which is similar to the method of overlapping regions (MOR) and the T-block method, requires field expansions in overlapping subdomains and subsequent mode matching. Results for surface current densities are compared with numerical results from COMSOL for problems involving wave scattering from PEC sectors of finite dimension. Results show that the subdomain approach can be as accurate as other numerical solutions and maybe more computationally efficient.

Molecular structures in the electronically excited (S1) and cationic (D0) states of 2-fluorothioanisole (2-FTA) have been precisely refined from the real-time dynamics of the femtosecond (fs) wavepacket prepared by the coherent excitation of the Franck-Condon active out-of-plane torsional modes in the S1 ← S0 transition at 285 nm. The simulation to reproduce the experiment in terms of the beating frequencies gives the nonplanar geometry of 2-FTA in S1, where the out-of-plane dihedral angle (φ) of the S-CH3 moiety is 51° with respect to the molecular plane. The behavior of the fs wavepacket in terms of the amplitudes and phases with the change of the probe (ionization) wavelength (λprobe = 300-330 nm) provides the otherwise veiled structure of the cationic D0 state. While the 2-FTA cation adopts the planar geometry (φ = 0°) at the global minimum, it is found to have a vertical minimum at φ ≈ 135° from the perspective of the D0 ← S1 vertical transition. Ab initio calculations support the experiment quite well although the simulation using the model potentials could improve the match with the experiment, giving the new interpretation for the previously disputed photoelectron spectroscopic results.

The excess electron in the dipole-bound state (DBS) of the anion is found to be recaptured into the excited valence orbital localized at the positive end of the dipole, leading to the chemical bond cleavage of the anion. In the DBS of the 4-iodophenoxide anion, the extremely loosely bound electron (binding energy of 53 cm-1) is recaptured into the πσ* valence orbital, which is repulsive along the C-I bond extension coordinate, leading to the iodide (I-) and phenoxyl diradical (·C6H4O·) channel at the asymptotic limit. This is the first real-time observation of the state-specific relaxation (other than autodetachment) dynamics of the DBS and subsequent chemical reaction. The lifetime of the 4-iodophenoxide DBS at its zero-point energy (ZPE), which is measured for the cryogenically cooled trapped anion using the picosecond laser pump-probe scheme, has been estimated to be ∼9.5 ± 0.3 ps. Quantum mechanical calculations support the efficient transition from the DBS (below the detachment threshold) to the low-lying πσ* valence orbital of the first excited state of the anion. Similar experiments on 4-chlorophenoxide and 4-bromophenoxide anions indicate that the electron recaptures into excited valence orbitals hardly occur in the DBS of those anions, giving the long lifetimes (≫ns) at ZPE, suggesting that the internal conversion to S0 may be the major relaxation pathway for those anions.

We investigated the potential probiotic properties of Limosilactobacillus fermentum KGC1601 isolated from Panax ginseng. Ginseng cultivated in an experimental field of the Korea Ginseng Research Institute was fermented, followed by single colony selection from MRS agar. We performed 16s-rRNA sequencing and whole-genome analysis to identify L. fermentum and evaluate the biosafety parameters of this strain, respectively. We confirmed this strain was susceptible to six antibiotics, as proposed by the European Food Safety Authority, did not produce biogenic amines, and did not exhibit any hemolytic activity. Acid resistance and bile salt tolerance, which are essential properties of a probiotic agent, were investigated. Notably, distinguishing properties of this strain were that it exhibited excellent bile salt tolerance and anti-inflammatory effects. The excellent bile salt tolerance was confirmed by scanning electron microscopy. Through qRT-PCR and ELISA studies, it was revealed that L. fermentum KGC1601 pre-treatment up-regulates anti-inflammatory cytokines and down-regulates pro-inflammatory cytokines in RAW 264.7 cells. Consequently, we suggested that L. fermentum KGC1601 can be safely used as a potential anti-inflammatory functional probiotic agent.

Anion chemical dynamics of autodetachment and fragmentation mediated by the dipole-bound state (DBS) have been thoroughly investigated in a state-specific way for the first time by employing the picosecond time-resolved or the nanosecond frequency-resolved spectroscopy combined with the cryogenically cooled ion trap and velocity-map imaging techniques. For the ortho-, meta-, or para-iodophenoxide anion (o-, m-, or p-IPhO-), the C-I bond rupture giving the anionic iodide (I-) fragment occurs via the nonadiabatic transition from the DBS to the nearby valence-bound states (VBS) of the anion where the vibronic coupling into the S1 (π-sigma*) state (which is repulsive along the C-I bond extension coordinate) should be largely responsible. The dynamic details are governed by the isomer-specific nature of the potential energy surfaces in the vicinity of the DBS-VBS curve crossings, as manifested in the huge different chemical reactivity of o-, m-, or p-IPhO-. It is confirmed here that the C-I bond dissociation is mediated by DBS resonances, providing the foremost evidence that the metastable DBS plays the essential role as the doorway into the anion chemistry especially of the dissociative electron attachment (DEA). The fragmentation channel is dominant when it is mediated by the DBS resonances located below the electron-affinity (EA) threshold, whereas it is kinetically adjusted by the competitive autodetachment process when the DBS resonances lying above EA convey the electron to the valence orbitals. The product yield of the C-I bond cleavage is strongly mode-dependent as the rate of the concomitant autodetachment is much influenced by the characteristics of the individual vibrational modes, paving a new way of the reaction control of the anion chemistry.

Mode-dependent H atom tunneling dynamics of the O–H bond predissociation of the S1 phenol has been theoretically analyzed. As the tunneling is governed by the complicated multi-dimensional potential energy surfaces that are dynamically shaped by the upper-lying S1(ππ*)/S2(πσ*) conical intersection, the mode-specific tunneling dynamics of phenol (S1) has been quite formidable to be understood. Herein, we have examined the topography of the potential energy surface along the particular S1 vibrational mode of interest at the nuclear configurations of the S1 minimum and S1/S2 conical intersection. The effective adiabatic tunneling barrier experienced by the reactive flux at the particular S1 vibrational mode excitation is then uniquely determined by the topographic shape of the potential energy surface extended along the conical intersection seam coordinate associated with the particular vibrational mode. The resultant multi-dimensional coupling of the specific vibrational mode to the tunneling coordinate is then reflected in the mode-dependent tunneling rate as well as nonadiabatic transition probability. Remarkably, the mode-specific experimental result of the S1 phenol tunneling reaction [K. C. Woo and S. K. Kim, J. Phys. Chem. A 123, 1529–1537 (2019)] (in terms of the qualitative and relative mode-dependent dynamic behavior) could be well rationalized by semi-classical calculations based on the mode-specific topography of the effective tunneling barrier, providing the clear conceptual insight that the skewed potential energy surfaces along the conical intersection seam (strongly or weakly coupled to the tunneling reaction coordinate) may dictate the tunneling dynamics in the proximity of the conical intersection.

Non-adiabatic couplings between Born–Oppenheimer (BO)-derived potential energy surfaces are now recognized as pivotal in describing the non-radiative decay of electronically excited molecules following photon absorption. This opinion piece illustrates how non-BO effects provide photostability to many biomolecules when exposed to ultraviolet radiation, yet in many other cases are key to facilitating ‘reactive’ outcomes like isomerization and bond fission. The examples are presented in order of decreasing molecular complexity, spanning studies of organic sunscreen molecules in solution, through two families of heteroatom containing aromatic molecules and culminating with studies of isolated gas phase H 2 O molecules that afford some of the most detailed insights yet available into the cascade of non-adiabatic couplings that enable the evolution from photoexcited molecule to eventual products. This article is part of the theme issue 'Chemistry without the Born–Oppenheimer approximation'.

Vibrio cholerae, cause of the life-threatening diarrheal disease cholera, can be divided into different serogroups based on the structure of its lipopolysaccharide (LPS), which consists of lipid-A, corepolysaccharide and O-antigen polysaccharide (O-PS). The O1 serogroup, the predominant cause of cholera, includes two major serotypes, Inaba and Ogawa. These serotypes are differentiated by the presence of a single 2-O-methyl group in the upstream terminal perosamine of the Ogawa O-PS, which is absent in the Inaba O-PS. To ensure the consistent quality and efficacy of the current cholera vaccines, accurate measurement and characterization of each of these two serotypes is highly important. In this study, we efficiently screened a phage-displayed human synthetic Fab library by bio-panning against Ogawa LPS and finally selected three unique mAbs (D9, E11, and F7) that specifically react with Ogawa LPS. The mAbs bound to Vibrio cholerae vaccine in a dose-dependent fashion. Sequence and structure analyses of antibody paratopes suggest that IgG D9 might have the same fine specificity as that of the murine mAbs, which were shown to bind to the upstream terminal perosamine of Ogawa O-PS, whereas IgGs F7 and E11 showed some different characteristics in the paratopes. To our knowledge, this study is the first to demonstrate the generation of Ogawa-specific mAbs using phage display technology. The mAbs will be useful for identification and quantification of Ogawa LPS in multivalent V. cholerae vaccines.

This study aimed to assess the impact of overactive bladder on health-related quality of life (HRQoL) in a community-based sample of Korean population. The data of adults aged 19 and over that who participated in the 2012 Korean Community Health Survey were analyzed. Overactive bladder severity was classified as normal, mild, moderate, or severe using the Overactive Bladder Symptom scores, and HRQoL was evaluated using EQ-5D-3L. Relations between HRQoL and the severities and symptoms of OAB were investigated. Sampling weighted adjusted multiple regression analysis was performed to determine the effect of OAB symptom severity on HRQoL. Of the 226,867 study subjects, 12,303 (5.4%) had OAB, and 552 (0.2%) had an OABSS of ≥ 12, indicating severe OAB. The problem -reporting rate significantly increased in all EQ-5D-3L dimensions as OAB severity increased. After adjusting for other variables, OAB severity had a significant effect on EQ-5D-3L index. Urge incontinence had greatest impact on quality of life. As the severity of OAB increased from mild to severe, quality of life decreased significantly. OAB was found to negatively affect HRQoL.

Multidimensional conical intersection seam has been characterized by utilizing the dynamic resonances in the nonadiabatic transition probability experimentally observed in the predissociation of thioanisole isotopomers. The nonadiabatic bifurcation behavior of the reactive flux into either the Herzberg type-I (electronic) or type-II (vibrational) predissociation pathway is found to be strongly dependent on the quantum nature of the S1/S2 vibronic eigenstate, providing the essential information about structure and dynamic character of the conical intersection seam projected onto the normal mode space. By modifying the nature of the normal mode space through partial or full H/D substitution of the molecule, multiple aspects of the conical intersection seam could be characterized from different viewpoints set by the adjusted normal mode space. Theoretical calculations of potential energy curves along selected normal mode displacements support the experiment.

The S–H bond dissociation dynamics of CH3SH have been investigated for the S1–S0 transition mediated by either the S–H stretching (2608 cm−1) or CH3 symmetric stretching (2951 cm−1) mode excitation in the S0 state. The S–H and C–S bond extensions are strongly coupled in the S1 state through the S1/S2 same-symmetry conical intersection, giving the C–S stretching mode excitation of the CH3S˙ fragment during the prompt S–H bond rupture on S1. In the IR + UV transition mediated by the S–H stretching mode, the vertical transition seems to access the Franck–Condon region where the S–H bond is shortened while the coupling to the C–S bond stretching becomes stronger compared to the case of one-photon UV transition, indicating that the intramolecular vibrational redistribution (IVR) is little activated in S0. When the IR + UV excitation is mediated by the CH3 symmetric stretching mode, on the other hand, the Franck–Condon region in S1 encompasses the enlarged molecular structures with respect to both S–H and C–S bond extensions, presumably due to the rapid IVR in S0 prior to the vertical transition. This leads to the inverted vibrational state population of the C–S bond stretching mode of the CH3S˙ fragment. This work demonstrates that the reaction dynamics upon the IR + UV excitation of CH3SH is highly mode dependent and the energy disposal dynamics could be controlled by the manipulation of the Franck–Condon region through the particular vibrational-state mediation in the ground state, shedding new light on the structure–dynamics relationship.

Ultrafast intersystem crossing (ISC) in transition metal complexes leads to a long-lived active state with a high yield, which leads to efficient light energy conversion. The detailed mechanism of ISC may lead to a rational molecular design of superior transition metal complexes. Coherent nuclear wave packets observed in femtosecond time-resolved spectroscopies provide important information on the excited-state dynamics. In particular, analyzing the nuclear wave packets in both the reactant and the product may unveil the molecular dynamics of an ultrafast reaction. In this study, experimental evidence proving the reaction coordinates of the ultrafast ISC of ruthenium(ii) complexes is presented using coherent vibrational spectroscopy with a quantum chemical simulation of coherent vibrational motion. We observed vibrational modes strongly coupled to the ISC, whose vibrational coherences undergo remarkable attenuation after the ISC. The coupled modes contain metal-ligand stretching or symmetry breaking components, and the faster ISC rates of lower-symmetry ruthenium(ii) complexes support the significance of the latter.

주주명부 제도 또는 명의개서 제도의 취지에 대해 일반적으로 회사의 사무 편익을 위한 것으로 이해한다. 이에 대해 일부 학설과 대법원의 변경된 판례는 상법 제337조 제1항의 명의개서를 하지 않으면 회사에 대항할 수 없다는 규정과 관련하여서는 앞서 밝힌 취지와 별도로 다수의 이해관계가 교차하는 회사의 법률관계를 획일적으로 처리하고자하는 의도도 있다고 한다. 주주명부 제도의 취지가 회사의 사무 편익을 위한 것이라면 이와 관련된 명의개서 제도의 취지나 효과가 달라야 할 이유가 없는데도 제도의 취지를 단지 회사와 주주 관계가 아니라 제3자까지 포함된 법률관계를 고려하였다는 점은 수긍하기 어렵다. 다른 한편 법이 ‘대항할 수 없다’라는 표현은 일반적으로 당사자 사이에 다툴 수 없음을 의미하고, 이를 넘어 제3자를 포함하는 때에는 법문에서 ‘제3자’를 밝힌다는 점에서 이러한 규정이 없음에도 회사와 주주 사이만이 아니라 회사와 제3자 또는 주주와 제3자 사이의 법률관계까지 규명하는 것으로 해석하는 것은 다소 무리한 해석이 아닌가 싶다. 단체적 관계에서 획일적 정형적으로 법률관계를 처리할 필요성이나 금융 거래나 부동산 거래에서실명제가 강화되고 있음을 들어 대법원의 견해에 찬성하는 견해가 있다. 그러나 회사가 실질 주주를 알고 있는 경우가 흔치 않아 알고 있는 실질 주주를 주주로 취급하는 게 비일비재한 사항도 아니고, 금융이나 부동산 거래에서의 형식화는 차명에 따른 거래의 혼란과 경제에 미치는 파급 효과가 지대하다는 이유로 제한한 것이다. 주식의 소유관계를 일일이 고려하면 다수의 주주가 관여하는 회사의 법률관계가 혼란에 빨질 우려가 있고 회사의 경영진에 주주권권의 행사에 개입하고 있어 남용을 방지하기 위해 필요하다고 한다. 그러나 회사가 명의 주주와 실질 주주가 다른 것을 알고 있는 예가 흔치 않으며, 문제는 우연하게 회사의 모든 이사와 감사가 실질 주주를 알게 된 경우까지도 이의 권리 행사를 부인하는 것은 무권리자의 권리 행사를 묵인하는 또 다른 부작용을 낳는다. 비록 형식 주주의 주주권을 인정한다고 하더라도 이 자가 무권리자임을 다투는 사안은 별도로 남는다. 결국에는 판결에 의할 수밖에 없는데, 법원이 형식 주주라는 측면에서 모두 권리자로 인정할수는 없으며, 바로 그 범위에서는 실질주주를 주주로 취급한다고 하더라도 같은 문제는 발생한다. 회사가 주주로 인정할 수 있다는 주장이지 주주로 취급하여야 한다는 것은 아니다. 따라서 회사가 실질주주를 알고 있더라도 형식주주에게 주주권을 행사하도록 하는 것은 문제되지 않는다. 다만 형식주주의 무권리를 알고 있음에도 권리행사를 묵인할 수 있는가는 검토되어야 한다. 우연하게 제3자를 통해 알고 있다는 사실만으로 회사가 알고 있다고 볼수는 없다고 본다. 회사의 이사나 감사 모두가 양자의 거래관계에 관여하여 양수도 사실을 알고 있다면 회사가 양수인을 주주로 보는 것이 큰 무리는 없다고 본다. 그러한 상황에서는 별도의 의사표시 없이 묵시적으로 명의개서를 요구한 것으로 보아야 한다. 물론 이러한 사실은 또 다른 법률관계가 이로부터 기인하기 전까지에 한한다. 즉 양도인의 주식에 대한 압류가 이루어진 이후의 법률관계에는 영향을 미치지 않는다고 보아야 한다.

Photofragmentation dynamics of cis and trans isomers of 1,2-dibromoethylene (1,2-DBE) have been investigated by multiphoton excitation using a picosecond (ps) laser pulse. It has been found that the Br2+ product ion preferentially originates from the cis isomer rather than from trans. The Boltzmann-type isotropic low kinetic energy components of the Br+ and Br2+ product state distributions seem to be most likely from the unimolecular reactions of the vibrationally hot cationic ground state generated by the three-photon absorption at the photon energy below ∼38 000 cm−1. The highly anisotropic kinetic energy components of Br+ and Br2+ start to appear at the photon energy above ∼38 000 cm−1, where the Dn (n ≥ 1) − D0 transition is facilitated within the same ps laser pulse as the parent molecule is efficiently ionized by the two-photon absorption. The transition dipole moment of the D4 − D0 transition of the strongest oscillator strength has been theoretically predicted to be parallel to the C–Br bond or C=C bond axis for the trans or cis isomer, respectively. The fast anisotropic with the (β ∼ +2) component in the Br+ product distribution is thus likely from the trans isomer, whereas that of Br2+ (β ∼ −0.5) should be the consequence of the photodissociation of the cis isomer. The isomer-specific reactivity found here in the picosecond multiphoton excitation of 1,2-DBE provides a nice platform for the better understanding of the structure–reactivity relationship under the harsh condition of the strong or ultrashort optical field.