The charge-carrier dynamics of anatase TiO2 nanoparticles in an aqueous solution were studied by femtosecond time-resolved X-ray absorption spectroscopy using an X-ray free electron laser in combination with a synchronized ultraviolet femtosecond laser (268 nm). Using an arrival time monitor for the X-ray pulses, we obtained a temporal resolution of 170 fs. The transient X-ray absorption spectra revealed an ultrafast Ti K-edge shift and a subsequent growth of a pre-edge structure. The edge shift occurred in ca. 100 fs and is ascribed to reduction of Ti by localization of generated conduction band electrons into shallow traps of self-trapped polarons or deep traps at penta-coordinate Ti sites. Growth of the pre-edge feature and reduction of the above-edge peak intensity occur with similar time constants of 300–400 fs, which we assign to the structural distortion dynamics near the surface.

Laser–microwave double resonance (LMDR) with high electric field was applied to the OCS molecule. Stark Lamb-dip spectra due to the infrared transitions of the 2ν2(0200–0000, 9.6 μm), 2ν1 (2000–0000, 5.8 μm), and ν1+2ν2 (1200–0000, 5.3 μm) bands were observed with the CO2 and CO lasers. The spectra due to the corresponding hot bands; 0310–0110, 0400–0200, 1200–1000, 1310–1110; 2110–0110, 3000–1000; 1400–0200, 1420–0220, 1510–0310, 2200–1000; and a few bands of OC34S and O13CS were also identified. Associated with these infrared transitions, more than 90 LMDR signals were detected and assigned to rotational transitions in the 11 vibrational states 0000, 1000, 2000, 0110, 0200, 0220, 0310, 0400, 1200, 1420, and 2200 of the normal species, and in the two vibrational states 0000 and 0200 of both OC34S and O13CS. Dipole moments were determined with accuracies (2.5σ) better than 2×10−5 D for all these vibrational states. Polarizability anisotropies were also obtained for some states. The data for the ground ν1 and ν2 vibrational states are, with the 2.5σ uncertainties in parentheses.From the Stark Lamb-dip spectra the origins of various vibrational bands were determined, among which those for the 0200–0000 and 0310–0110 bands are 31 389 530.4(25) and 31 566 477.57(67) MHz, respectively. The dipole moments and band origins obtained in the present study agree well with the available accurate values from molecular beam electric resonance and heterodyne measurement, respectively. A procedure for the calibration of electric field in laser Stark and double resonance spectroscopy, in which the dipole moment of OCS is used as the standard, is described.

In haemoglobin the change from the low-spin (LS) hexacoordinated haem to the high spin (HS, S = 2) pentacoordinated domed deoxy-myoglobin (deoxyMb) form upon ligand detachment from the haem and the reverse process upon ligand binding are what ultimately drives the respiratory function. Here we probe them in the case of Myoglobin-NO (MbNO) using element-and spin-sensitive femtosecond Fe K α and K β X-ray emission spectroscopy at an X-ray free-electron laser (FEL). We find that the change from the LS (S = 1/2) MbNO to the HS haem occurs in~800 fs, and that it proceeds via an intermediate (S = 1) spin state. We also show that upon NO recombination, the return to the planar MbNO ground state is an electronic relaxation from HS to LS taking place in~30 ps. Thus, the entire ligand dissociation-recombination cycle in MbNO is a spin cross-over followed by a reverse spin cross-over process.

Carbon nanowalls (CNWs), vertically standing highly crystallizing graphene sheets, were used in the application of a surface-assisted laser desorption/ionization time-of-flight mass spectrometry (SALDI-TOF-MS). The CNW substrates solved the issues on interferences of matrix molecules and alkali metal addition ions in low-weight molecule detection. Before SALDI sample preparations, the hydrophobic CNW was treated by atmospheric pressure plasma for exposing hydrophilicity to the CNWs’ surface. Detection of water soluble amino acids, arginine, was demonstrated.

Objective: This study investigates the use of serum DUPAN-2 in predicting the PC progression in CA19-9 nonsecretors. Background: Although we previously reported that serum CA19-9 > 500U/ mL is a poor prognostic factor and an indication for enhanced neoadjuvant treatment, there is not a biomarker surrogate that equivalently predicts prognosis for CA19-9 nonsecretors. Methods: We evaluated consecutive PC patients who underwent pancreatectomy from 2005 to 2019. All patients were categorized as either nonsecretor or secretor (CA19-9 ≤ or > 2.0U/mL). Results: Of the 984 resected PC patients, 94 (9.6%) were nonsecretors and 890 (90.4%) were secretors. The baseline characteristics were not statistically different between the 2 groups except for the level of DUPAN-2 (720 vs. 100U/mL, P < 0.001). Survival curves after resection were similar between the 2 groups (29.4 months vs. 31.3 months, P = 0.900). Survival curves of patients with DUPAN-2 > 2000U/mL in the nonsecretors and patients with CA19-9 > 500U/mL in the secretors were nearly equivalent as well (hazard ratio 2.08 vs. 1.89). In the multivariate analysis, DUPAN-2 > 2000U/mL (hazard ratio 2.53, P = 0.010) was identified as independent prognostic factor after resection. Conclusion: DUPAN-2 > 2000U/mL in CA19-9 nonsecretors can be an unfavorable factor that corresponds to CA19-9 > 500U/mL in CA19-9 secretors which is an indicator for enhanced neoadjuvant treatment. The current results shed light on the subset of nonsecretors with poor prognosis that were traditionally categorized in a group with a more favorable prognosis group.