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Photochemical reactions in solution are governed by a complex interplay between transient intramolecular electronic and nuclear structural changes and accompanying solvent rearrangements. State-of-the-art time-resolved X-ray solution scattering has emerged in the last decade as a powerful technique to observe solute and solvent motions in real time. However, disentangling solute and solvent dynamics and how they mutually influence each other remains challenging. Here, we simultaneously measure femtosecond X-ray emission and scattering to track both the intramolecular and solvation structural dynamics following photoexcitation of a solvated copper photosensitizer. Quantitative analysis assisted by molecular dynamics simulations reveals a two-step ligand flattening strongly coupled to the solvent reorganization, which conventional optical methods could not discern. First, a ballistic flattening triggers coherent motions of surrounding acetonitrile molecules. In turn, the approach of acetonitrile molecules to the copper atom mediates the decay of intramolecular coherent vibrations and induces a further ligand flattening. These direct structural insights reveal that photoinduced solute and solvent motions can be intimately intertwined, explaining how the key initial steps of light harvesting are affected by the solvent on the atomic time and length scale. Ultimately, this work takes a step forward in understanding the microscopic mechanisms of the bidirectional influence between transient solvent reorganization and photoinduced solute structural dynamics.

Photo-induced oxidation-enhancement in biomimetic bridged Ru(ii)-Mo(vi) photo-catalyst is unexpectedly photo-activated in ps timescales. One-photon absorption generates an excited state where both photo-oxidized and photo-reduced catalytic centres are activated simultaneously and independently.

Light-harvesting materials, such as the N719 dye, have been introduced as one of the next-generation energy sources. Photophysical and electrochemical studies on such systems have been carried out to understand the light-harvesting phenomena with a particular interest in noble-metal free photosensitizers and photocatalysts. The realization of ultrashort optical and X-ray pulses together with their spectroscopic applications enabled to finely trace the corresponding ultrafast changes in the photosensitizers and photocatalysts, both globally and locally. This study investigates the ultrafast dynamics of energy conversion in model complexes by means of ultrafast optical and X-ray methods to obtain more insights into their steady state performances. Differences in the optical absorption spectrum with respect to the arrival time changes between two pulses revealed a global interaction in a bimetallic photocatalyst such as Ir(III)-Co(III) triads, Ru(II)-Mo(VI) dyads, and Fe(II)-Co(III) dyads. Complementary to this, time-resolved X-ray absorption and emission spectroscopy visualized the electronic and geometric structure changes of the target element that inherently trigger the relevant chemical events in photoactive molecules like Ru(II), Cu(I), and Fe(II) photosensitizers. This study finds that the 3d-chelates undergo a femtosecond symmetry breaking after the charge separation that often recombines non-radiatively, whereas the 4d- and 5d-chelates with their chemical potential in the charge separation state can perturb the nearby electron densities such that either a chemical energy or an electron gets transferred on the picosecond timescale.

Chemistry - a European journal 27(38), 9905 - 9918 (2021). doi:10.1002/chem.202100766, A new base metal iron-cobalt dyad has been obtained by connection between a heteroleptic tetra-NHC iron(II) photosensitizer combining a 2,6-bis[3-(2,6-diisopropylphenyl)imidazol-2-ylidene]pyridine with 2,6-bis(3-methyl-imidazol-2-ylidene)-4,4���-bipyridine ligand, and a cobaloxime catalyst. This novel iron(II)-cobalt(III) assembly has been extensively characterized by ground- and excited-state methods like X-ray crystallography, X-ray absorption spectroscopy, (spectro-)electrochemistry, and steady-state and time-resolved optical absorption spectroscopy, with a particular focus on the stability of the molecular assembly in solution and determination of the excited-state landscape. NMR and UV/Vis spectroscopy reveal dissociation of the dyad in acetonitrile at concentrations below 1 mM and high photostability. Transient absorption spectroscopy after excitation into the metal-to-ligand charge transfer absorption band suggests a relaxation cascade originating from hot singlet and triplet MLCT states, leading to the population of the $^{3}$MLCT state that exhibits the longest lifetime. Finally, decay into the ground state involves a $^{3}$MC state. Attachment of cobaloxime to the iron photosensitizer increases the $^{3}$MLCT lifetime at the iron centre. Together with the directing effect of the linker, this potentially makes the dyad more active in photocatalytic proton reduction experiments than the analogous two-component system, consisting of the iron photosensitizer and Co(dmgH)$_2$(py)Cl. This work thus sheds new light on the functionality of base metal dyads, which are important for more efficient and sustainable future proton reduction systems., Published by Wiley-VCH, Weinheim

Femtosecond electronic and nuclear dynamics in [Cu(dmp)2]+ complex upon 550 nm photoexcitation are studied with X-ray emission spectroscopy and X-ray solution scattering, revealing pseudo Jahn-Teller distortion (~410 fs) coupled with coherent vibrational motion.

The Femtosecond X-ray Experiments scientific instrument is a versatile instrument for ultrafast pump–probe X-ray absorption, emission and scattering experiments at the European XFEL; the instrumentation, commissioning results and operation performance status are presented., The European X-ray Free-Electron Laser (EuXFEL) delivers extremely intense (>1012 photons pulse−1 and up to 27000 pulses s−1), ultrashort (

This study was to investigate the choice & satisfaction factors of a musical as culture contents, and I will recognize it about relation between these two factors. To achieve this, I did a survey with spectators of . Factors analysis and simple/multi regression analysis are utilized as data analytical methods. The choice factors of musical showed that it was five factors extracted a price and facilities, production and directing, marketing, musical quality, OSMU. The satisfaction factors of musical was four factors extracted a production company and trust of advertisement, artistic presentation, harmony of All members of the cast, level of leading actor or actress. The choice of musical influenced satisfaction factors showed that it as performance prices and facilities level is reasonable, and spectators expect high satisfaction regarding a performance. Analysts say that, Pricing to be exposed to quality of a work in order to raise musical satisfaction shall be performed. Also, An exaggerated performance marketing is negative to satisfaction of an audience compare with quality of a work it was confirmed to affect. This study suggests that important point is planning, directing and marketing of a musical.

The purpose of this research is to develop a diagnostic reference level for computed tomography (CT) suitable for Korean medical purposes. The direction of CT application and details on patient dose were investigated by survey, and the dose measurement is targeted in general hospitals registered with the Korean Hospital Association. The dose measurement was done with head and body phantom, and an accurate dosimeter was utilised in medical institutions that participated in the survey. The survey and dose measurements on the patient dose showed that the 75th percentiles in the distribution of weighted CT dose index (CTDIw) were 50.5 and 45.4 mGy for the head and 14.4 and 25.30 mGy for the body portions, respectively. Based on these research data, the target patient doses that are believed to be achievable for CT examination in Korean circumstances are about 48 +/- 4 mGy in the head and 20 +/- 8 mGy in the body.

Objective The objective of this study was to examine the effectiveness of a meditation-based stress management program in patients with anxiety disorder. Methods Patients with anxiety disorder were randomly assigned to an 8-week clinical trial of either a meditation-based stress management program or an anxiety disorder education program. The Hamilton Anxiety Rating Scale (HAM-A), the Hamilton Depression Rating Scale (HAM-D), the State–Trait Anxiety Inventory (STAI), the Beck Depression Inventory, and the Symptom Checklist-90—Revised (SCL-90-R) were used to measure outcome at 0, 2, 4, and 8 weeks of the program. Results Compared to the education group, the meditation-based stress management group showed significant improvement in scores on all anxiety scales (HAM-A, P =.00; STAI state, P =.00; STAI trait, P =.00; anxiety subscale of SCL-90-R, P =.00) and in the SCL-90-R hostility subscale ( P =.01). Findings on depression measures were inconsistent, with no significant improvement shown by subjects in the meditation-based stress management group compared to those in the education group. The meditation-based stress management group did not show significant improvement in somatization, obsessive–compulsive symptoms, and interpersonal sensitivity scores, or in the SCL-90-R phobic anxiety subscale compared to the education group. Conclusions A meditation-based stress management program can be effective in relieving anxiety symptoms in patients with anxiety disorder. However, well-designed, randomized, and controlled trials are needed to scientifically prove the worth of this intervention prior to treatment.

Owing to its high carrier mobility, conductivity, flexibility and optical transparency, graphene is a versatile material in micro- and macroelectronics. However, the low density of electrochemically active defects in graphene synthesized by chemical vapour deposition limits its application in biosensing. Here, we show that graphene doped with gold and combined with a gold mesh has improved electrochemical activity over bare graphene, sufficient to form a wearable patch for sweat-based diabetes monitoring and feedback therapy. The stretchable device features a serpentine bilayer of gold mesh and gold-doped graphene that forms an efficient electrochemical interface for the stable transfer of electrical signals. The patch consists of a heater, temperature, humidity, glucose and pH sensors and polymeric microneedles that can be thermally activated to deliver drugs transcutaneously. We show that the patch can be thermally actuated to deliver Metformin and reduce blood glucose levels in diabetic mice.