Tracking the structural change of the predissociating molecule near the transition state.

Despite its profound significance, the molecular structural changes near the transition state, driven by the vibronic coupling, have remained largely unexplored, leaving a crucial aspect of chemical reactions shrouded in uncertainty. Herein, the dynamical behavior of the reactive flux on the verge of chemical bond breakage was revealed through the spectroscopic characterization of a large amplitude vibrational motion. Highly excited internal rotor states of S methylamine (CHND) report on the structural change as the molecule approaches the transition state, indicating that the quasi-free internal rotation is strongly coupled to the reaction coordinate as their energies near the maximum of the reaction barrier for the N-D chemical bond predissociation.

Spectroscopy and Dynamics of the Dipole-Bound States of -, -, and -Methylphenolate Anions.

A photodetachment and photoelectron spectroscopic study by employing a cryogenically cooled ion trap combined with a velocity-map imaging setup has been carried out to unravel the vibrational structures and autodetachment dynamics of the dipole-bound states (DBSs) of -, -, and -methylphenolate anions (-, -, and -CHPhO). The electron binding energy of the DBS increases monotonically with the increase of the neutral dipole moment to give respective values of 66 ± 15, 123 ± 18, or 154 ± 14 cm for the -, -, or -isomer. The different electron-donating effects of the methyl moieties in the three geometrically different isomers seem to be reflected in the experiment.

Chlorine Substitution Effect on the S Relaxation Dynamics of Chlorobenzene and Chlorophenols.

The S state relaxation dynamics of chlorobenzene (CB), 3-chlorophenol (3-CP), 3-CP·HO, and 2-chlorophenol·HO (2-CP·HO) have been investigated by means of picosecond time-resolved pump-probe spectroscopy in a state-specific manner. For CB, the S state relaxes via the S-S internal conversion in the low internal energy region (<2000 cm), whereas the direct C-Cl bond dissociation channel mediated by the upper-lying repulsive πσ* state is opened to give the rather sharp increase of the S relaxation rate in the high internal energy region (>2000 cm). A similar dynamic feature has been observed for 3-CP in terms of the lifetime behavior with an increase in the S internal energy, suggesting that the H atom tunneling dissociation reaction from OH might contribute less compared to the internal conversion, although it is not clear at the present time whether or not the sharp increase of the S relaxation rate in the high internal energy region of 3-CP (>1500 cm) is entirely due to that of the internal conversion.

Korean Red Ginseng alleviates dextran sodium sulfate-induced colitis through gut microbiota modulation in mice.

Background: There is a growing interest in understanding the association between the gut microbiota and inflammatory bowel disease (IBD). Natural compounds, such as Korean Red Ginseng (KRG), show promise for IBD treatment because of their ability to influence gut microbiota. This study explored the effects of KRG on gut microbiota modulation and subsequent intestinal epithelial cell regeneration in an experimental colitis model.

Dynamic Interplay between the Mode-Randomization and Autodetachment of the Dipole-Bound States of the Anion.

State-specific dynamics of the dipole-bound state (DBS) of the cryogenically cooled deprotonated 4,4'-biphenol anion have been investigated by picosecond time-resolved pump-probe spectroscopy. For DBS vibrational states below the electron-detachment threshold, the relaxation rate is slow to give a lifetime (τ) longer than ∼5 ns, and it is attributed to the nonvalence-to-valence orbital transformation. For the DBS resonances above the detachment threshold, however, the lifetime decreases with the activation of autodetachment, whereas the otherwise zeroth DBS modes seem to be randomized by intramolecular vibrational energy redistribution (IVR), as manifested in the biexponential transients.

Signatures of Dynamically Dressed States.

The interaction of a resonant light field with a quantum two-level system is of key interest both for fundamental quantum optics and quantum technological applications employing resonant excitation. While emission under resonant continuous-wave excitation has been well studied, the more complex emission spectrum of dynamically dressed states-a quantum two-level system driven by resonant pulsed excitation-has so far been investigated in detail only theoretically. Here, we present the first experimental observation of the complete resonance fluorescence emission spectrum of a single quantum two-level system, in the form of an excitonic transition in a semiconductor quantum dot, driven by finite Gaussian pulses.

Electron-Binding Dynamics of the Dipole-Bound State: Correlation Effect on the Autodetachment Dynamics.

The nature of the electron-binding forces in the dipole-bound states (DBS) of anions is interrogated through experimental and theoretical means by investigating the autodetachment dynamics from DBS Feshbach resonances of -, -, and -bromophenoxide (BrPhO). Though the charge-dipole electrostatic potential has been widely regarded to be mainly responsible for the electron binding in DBS, the effect of nonclassical electron correlation has been conceived to be quite significant in terms of its static and/or dynamic contributions toward the binding of the excess electron to the neutral core. State-specific real-time autodetachment dynamics observed by picosecond time-resolved photoelectron velocity-map imaging spectroscopy reveal that the autodetachment processes from the DBS Feshbach resonances of BrPhO anions cannot indeed be rationalized by the conventional charge-dipole potential.

Excited-state chemistry of the nitromethane anion mediated by the dipole-bound states revealed by photofragment action spectroscopy.

We report the first experimental observation of the excited dipole-bound state (DBS) of the cryogenically cooled nitromethane anion (CHNO), where the excess electron is loosely attached to the singlet or triplet neutral-core. Photofragment and photodetachment action spectra have been employed for the dynamic exploration of Feshbach resonances located even far above the electron detachment threshold, giving excitation profiles from the ground anionic state (D) to the DBSs which match quite well with the spectral structures of the photoelectron spectra. This indicates that the electron transfer from the nonvalence orbital (of DBS) to the valence orbital (of anion) is mainly responsible for the anionic fragmentation channels, giving strong evidence for that the DBS plays a dynamic doorway-role in the anionic fragmentation reactions.

Photodissociation dynamics of m- and p-cresol in the S1 state: Interplay between the mode-randomization and H atom tunneling reaction.

The H atom tunneling dissociation dynamics of the S1 state of meta- or para-cresol has been investigated by using the picosecond time-resolved pump-probe spectroscopy in a state-specific manner. The S1 state lifetime (mainly due to the H atom tunneling reaction) is found to be mode-dependent whereas it quickly converges and remains constant as the rapid intramolecular vibrational energy redistribution (IVR) starts to participate in the S1 state relaxation with the increase of the S1 internal energy (Eint). The IVR rate and its change with increasing Eint have been reflected in the parent ion transients taken by tuning the total energy (hνpump + hνprobe) just above the adiabatic ionization threshold (so that the dissipation of the initial mode-character could be monitored as a function of the reaction time), indicating that the mode randomization rate into the S1 isoenergetic manifolds exceeds the tunneling rate quite early in terms of Eint for m-cresol (≤∼1200 cm-1) or p-cresol (≤∼800 cm-1) compared to the case of phenol (≤∼1800 cm-1).

Dynamic Role of the Intramolecular Hydrogen Bonding in the S State Relaxation Dynamics Revealed by the Direct Measurement of the Mode-Dependent Internal Conversion Rate of 2-Chlorophenol and 2-Chlorothiophenol.

The dynamic role of the intramolecular hydrogen bond in the S relaxation of -2-chlorophenol (2-CP) or -2-chlorothiophenol (2-CTP) has been investigated in a state-specific manner. Whereas ultrafast internal conversion is dominant for 2-CP, the H-tunneling competes with internal conversion for 2-CTP even at the S origin. The S-S internal conversion rate of 2-CTP could be directly measured from the S lifetimes of 2-CTP- (Cl-CH-SD) as the D-tunneling is kinetically blocked, allowing distinct estimations of tunneling and internal conversion rates with increasing the energy.

Comparing Korea Occupational Safety & Health Agency and National Health Insurance Service's cardio-cerebrovascular diseases risk-assessment tools using data from one hospital's health checkups.

Background: Cardio-cerebrovascular diseases (CVDs) are the most common cause of death worldwide. Various CVD risk assessment tools have been developed. In South Korea, the Korea Occupational Safety & Health Agency (KOSHA) and the National Health Insurance Service (NHIS) have provided CVD risk assessments with health checkups.

Korea Seroprevalence Study of Monitoring of SARS-COV-2 Antibody Retention and Transmission (K-SEROSMART): findings from national representative sample.

Objectives: We estimated the population prevalence of antibodies to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), including unreported infections, through a Korea Seroprevalence Study of Monitoring of SARS-CoV-2 Antibody Retention and Transmission (K-SEROSMART) in 258 communities throughout Korea.

Methods: In August 2022, a survey was conducted among 10,000 household members aged 5 years and older, in households selected through two stage probability random sampling. During face-to-face household interviews, participants self-reported their health status, COVID-19 diagnosis and vaccination history, and general characteristics.

Multilayer Coating with Red Ginseng Dietary Fiber Improves Intestinal Adhesion and Proliferation of Probiotics in Human Intestinal Epithelial Models.

To exert their beneficial effects, it is essential for the commensal bacteria of probiotic supplements to be sufficiently protected as they pass through the low pH environment of the stomach, and effectively colonize the intestinal epithelium downstream. Here, we investigated the effect of a multilayer coating containing red ginseng dietary fiber, on the acid tolerance, and the adhesion and proliferation capacities of three strains ( KGC1901, KGC1201, KGC1601) isolated from , using HT-29 cells, mucin-coated plates, and human pluripotent stem cell-derived intestinal epithelial cells as in vitro models of human gut physiology. We observed that the multilayer-coated strains displayed improved survival rates after passage through gastric juice, as well as high adhesion and proliferation capacities within the various gut epithelial systems tested, compared to their uncoated counterparts.

Noninvasive and Continuous Monitoring of the Core Body Temperature through the Quantitative Measurement of Blood Perfusion Rate.

Core body temperature (CBT) is one of the four vital signs that must be monitored continuously. The continuous recording of CBT is possible through invasive methods by inserting a temperature probe into specific body sites. We report a novel method to monitor CBT through the quantitative measurement of skin blood perfusion rate (ω).

Red ginseng dietary fiber promotes probiotic properties of and alters bacterial metabolism.

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 with RGDF supplementation.

Mode-dependent H atom tunneling dynamics of the S phenol is resolved by the simple topographic view of the potential energy surfaces along the conical intersection seam.

Mode-dependent H atom tunneling dynamics of the O-H bond predissociation of the S 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 S(ππ*)/S(πσ*) conical intersection, the mode-specific tunneling dynamics of phenol (S) has been quite formidable to be understood. Herein, we have examined the topography of the potential energy surface along the particular S vibrational mode of interest at the nuclear configurations of the S minimum and S/S conical intersection.

Probiotic Characteristics and Safety Assessment of KGC1201 Isolated from .

is one of the most important herbal medicinal plants consumed as health functional food and can be fermented to achieve better efficacy. , one of the representative genera among lactic acid bacteria (LAB), has also been used as a probiotic material for health functional foods due to its beneficial effects on the human body. To achieve a synergistic effect by using these excellent dietary supplement ingredients together, a novel LAB strain was isolated from the root of 6-year-old ginseng.

Growth promotion effect of red ginseng dietary fiber to probiotics and transcriptome analysis of .

Background: Red ginseng marc, the residue of red ginseng left after water extraction, is rich in dietary fiber. Dietary fiber derived from fruits or vegetables can promote the proliferation of probiotics, and it is a key technology in the food industry to increase the productivity of probiotics by adding growth-enhancing substances such as dietary fiber. In this study, the effect of red ginseng dietary fiber (RGDF) on the growth of probiotic bacterial strains was investigated at the phenotypic and genetic levels.

πσ*-Mediated Nonadiabatic Tunneling Dynamics of Thiophenols in S: The Semiclassical Approaches.

The S-H bond tunneling predissociation dynamics of thiophenol and its -substituted derivatives (2-fluorothiophenol, 2-methoxythiophenol, and 2-chlorothiphenol) in S (ππ*) where the H atom tunneling is mediated by the nearby S (πσ*) state (which is repulsive along the S-H bond extension coordinate) have been investigated in a state-specific way using the picosecond time-resolved pump-probe spectroscopy for the jet-cooled molecules. The effects of the specific vibrational mode excitations and the SH/SD substitutions on the S-H(D) bond rupture tunneling dynamics have been interrogated, giving deep insights into the multidimensional aspects of the S/S conical intersection, which also shapes the underlying adiabatic tunneling potential energy surfaces (PESs). The semiclassical tunneling rate calculations based on the Wentzel-Kramers-Brillouin (WKB) approximation or Zhu-Nakamura (ZN) theory have been carried out based on the ab initio PESs calculated in the (one, two, or three) reduced dimensions to be compared with the experiment.

DS0384 promotes intestinal epithelial maturation via the postbiotic effect in human intestinal organoids and infant mice.

Little is known about the modulatory capacity of the microbiota in early intestinal development. We examined various intestinal models that respond to gut microbial metabolites based on human pluripotent stem cell-derived human intestinal organoids (hIOs): physiologically relevant fetal-like intestine, intestinal stem cell, and intestinal disease models. We found that a newly isolated strain DS0384 accelerated maturation of the fetal intestine using 3D hIO with immature fetal characteristics.

Experimental Observation of the Resonant Doorways to Anion Chemistry: Dynamic Role of Dipole-Bound Feshbach Resonances in Dissociative Electron Attachment.

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 -, -, or -iodophenoxide anion (-, -, or -IPhO), the C-I bond rupture occurs via the nonadiabatic transition from the DBS to the nearby valence-bound states (VBS) of the anion where the vibronic coupling into the S (πσ*) state (repulsive along the C-I bond extension coordinate) should be largely responsible. 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 -, -, or -IPhO.

Anti-Inflammatory Effects of KGC1601 Isolated from and Its Probiotic Characteristics.

We investigated the potential probiotic properties of KGC1601 isolated from . 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 and evaluate the biosafety parameters of this strain, respectively.

Dynamic role of the correlation effect revealed in the exceptionally slow autodetachment rates of the vibrational Feshbach resonances in the dipole-bound state.

Real-time autodetachment dynamics of the loosely bound excess electron from the vibrational Feshbach resonances of the dipole-bound states (DBS) of 4-bromophonoxide (4-BrPhO) and 4-chlorophenoxide (4-ClPhO) anions have been thoroughly investigated. The state-specific autodetachment rate measurements obtained by the picosecond time-resolved pump-probe method on the cryogenically cooled anions exhibit an exceptionally long lifetime () of ∼823 ± 156 ps for the 11' vibrational mode of the 4-BrPhO DBS. Strong mode-dependency in the wide dynamic range has also been found, giving ∼ 5.