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Three-photon double excitation of He in intense EUV FEL fields is studied by the shot-by-shot photoelectron spectroscopy, revealing the enhancement by resonances to the doubly excited states converging to the He+ N=3 level.

The correlated motion of the two deuterium atoms associated with the hydrogen migration and structural deformation to non-planar geometry are identified in acetylene dication by the time-resolved four-body Coulomb explosion imaging.

Femtosecond dynamics of molecular vibrations as well as cage motions in the B←X transition of Cl2 in solid Ar have been investigated. We observed molecular vibrational wave-packet motion in experimental pump-probe spectra and an additional oscillation with a 500 fs period which is assigned to the zone-boundary phonon of the Ar crystal. The cage motion is impulsively driven by the B←X transition due to the expansion of the electronic cloud of the chromophore. To clarify the underlying mechanism, we performed simulations based on the diatomics-in-molecules method which takes into account the different shapes of the Cl2 electronic wave function in the B and X states as well as the anisotropic interaction with the matrix. The simulation results show that Ar atom motion in the (100) plane is initiated by the electronic transition and that only those Ar atoms oscillate coherently with an ∼500 fs period which are essentially decoupled from the molecular vibration. Their phase and time evolution are in good agreement with the experimentally observed oscillation, supporting the assignment as a displacive excitation of coherent phonons. [ABSTRACT FROM AUTHOR]

Time-resolved extreme ultraviolet spectroscopy was used to investigate photodissociation within the iodobenzene C-band. The carbon-iodine bond of iodobenzene was photolyzed at 200 nm, and the ensuing dynamics were probed at 10.3 nm (120 eV) over a 4 ps range. Two product channels were observed and subsequently isolated by using a global fitting method. Their onset times and energetics were assigned to distinct electron transfer dynamics initiated following site-selective ionization of the iodine photoproducts, enabling the electronic states of the phenyl fragments to be identified using a classical over-the-barrier model for electron transfer. In combination with previous theoretical work, this allowed the corresponding neutral photochemistry to be assigned to (1) dissociation via the 7B 2 , 8A 2 , and 8B 1 states to give ground-state phenyl, Ph(X), and spin-orbit excited iodine and (2) dissociation through the 7A 1 and 8B 2 states to give excited-state phenyl, Ph(A), and ground-state iodine. The branching ratio was determined to be 87 ± 4% Ph(X) and 13 ± 4% Ph(A). Similarly, the corresponding amount of energy deposited into the internal phenyl modes in these channels was determined to be 44 ± 10 and 65 ± 21%, respectively, and upper bounds to the channel rise times were found to be 114 ± 6 and 310 ± 60 fs., Competing Interests: The authors declare no competing financial interest., (© 2024 The Authors. Published by American Chemical Society.)

The dissociative double ionization of CH3I and CH2I2 irradiated with extreme ultraviolet light at hv = 100 eV is investigated by multi-electron-ion coincidence spectroscopy using a magnetic bottle type electron spectrometer. The spin-orbit state-resolved Auger electron spectra for the I 4d core-hole states, (I 4d3/2)-1 and (I 4d5/2)-1, provide clear identifications of electronic states of CH3I2+ and CH2I22+. The dominant ion species produced after the double ionization correlate with the Auger electron energy, showing that different fragmentation pathways are open depending on the electronic states populated by the Auger decay. Theoretical calculations are performed to understand the fragmentation from the doubly charged states and the observed spin-orbit specificity in the Auger decay., (© 2024 Author(s). Published under an exclusive license by AIP Publishing.)

C-I bond extension and fission following ultraviolet (UV, 262 nm) photoexcitation of 2- and 3-iodothiophene is studied using ultrafast time-resolved extreme ultraviolet (XUV) ionization in conjunction with velocity map ion imaging. The photoexcited molecules and eventual I atom products are probed by site-selective ionization at the I 4d edge using intense XUV pulses, which induce multiple charges initially localized to the iodine atom. At C-I separations below the critical distance for charge transfer (CT), charge can redistribute around the molecule leading to Coulomb explosion and charged fragments with high kinetic energy. At greater C-I separations, beyond the critical distance, CT is no longer possible and the measured kinetic energies of the charged iodine atoms report on the neutral dissociation process. The time and momentum resolved measurements allow determination of the timescales and the respective product momentum and kinetic energy distributions for both isomers, which are interpreted in terms of rival 'direct' and 'indirect' dissociation pathways. The measurements are compared with a classical over the barrier model, which reveals that the onset of the indirect dissociation process is delayed by ∼1 ps relative to the direct process. The kinetics of the two processes show no discernible difference between the two parent isomers, but the branching between the direct and indirect dissociation channels and the respective product momentum distributions show isomer dependencies. The greater relative yield of indirect dissociation products from 262 nm photolysis of 3-iodothiophene ( cf. 2-iodothiophene) is attributed to the different partial cross-sections for (ring-centred) π∗ ← π and (C-I bond localized) σ∗ ← (n/π) excitation in the respective parent isomers.

Wave packet interferometry with vacuum ultraviolet light has been used to probe a complex region of the electronic spectrum of molecular nitrogen, N2. Wave packets of Rydberg and valence states were excited by using double pulses of vacuum ultraviolet (VUV), free-electron-laser (FEL) light. These wave packets were composed of contributions from multiple electronic states with a moderate principal quantum number (n ∼ 4-9) and a range of vibrational and rotational quantum numbers. The phase relationship of the two FEL pulses varied in time, but as demonstrated previously, a shot-by-shot analysis allows the spectra to be sorted according to the phase between the two pulses. The wave packets were probed by angle-resolved photoionization using an infrared pulse with a variable delay after the pair of excitation pulses. The photoelectron branching fractions and angular distributions display oscillations that depend on both the time delays and the relative phases of the VUV pulses. The combination of frequency, time delay, and phase selection provides significant control over the ionization process and ultimately improves the ability to analyze and assign complex molecular spectra., (© 2024 Author(s). Published under an exclusive license by AIP Publishing.)

Purpose: Preoperative pain is known as one of the most powerful risk factors for chronic postoperative inguinal pain (CPIP), while its pathogenesis has not been fully elucidated. The aim of the present study was to evaluate patients with preoperative pain from the pathological perspective and discuss the potential pathogenesis of CPIP in those patients., Methods: This was a single-institutional retrospective study. The study population was inguinal hernia patients with preoperative pain who underwent open anterior hernia repair for primary inguinal hernia with pragmatic ilioinguinal neurectomy during surgery between March 2021 and March 2023. The primary and secondary outcomes were proportion of collagen deposition and mucus accumulation within ilioinguinal nerve in those patients, respectively, which were evaluated histologically using Image J software., Results: Forty patients were evaluated. Median value of proportion of intraneural collagen deposition was 38.3% (27.7-95.9). These values were positively correlated with the duration of pain (r 2 =0.468, P<0.001). Median value of proportion of mucus accumulation in ilioinguinal nerve was 50.1% (0-82.0). These values had no correlation with any clinicopathological variables., Conclusions: In the present study population, all patients with preoperative pain had intraneural fibrosis within ilioinguinal nerve, and its degree had a positive correlation with the pain duration., (© 2023. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Background: Laparoscopic total gastrectomy for gastric cancer is still a demanding operation because of technical difficulties, especially of intracorporeal esophago-jejunal anastomosis., Methods: We introduced a newly designed method of anvil placement of circular stapling devices (CS) for laparoscopic esophagojejunostomy (EJS). A small incision was made on the anterior wall of the stomach, from which the anvil was inserted into the stomach and proceeded to the thoracic esophagus. Then, the abdominal esophagus was transected by a linear stapler, and the anvil into the esophagus was drawn back to the esophageal stump by pulling out the cotton tape pre-attached to the anvil. Intracorporeal EJS by Roux-en-Y reconstruction was performed by CS inserted into the abdominal cavity from the umbilical wound., Results: A total of consecutive 200 gastric cancer patients underwent laparoscopic total gastrectomy using this method. There was no operative mortality. Anastomotic complications occurred in 12 cases (6.0%): 9 cases of stenosis (4.5%) and 3 cases of bleedings (1.5%). Anastomotic leakage was not observed. As for non-anastomotic complications, there occurred 2 pulmonary complications (1.0%), 3 pancreatic leakages (1.5%), and 8 bowel obstructions due to internal hernia (4.0%). With a median follow-up period of 47.1 months, 5-year overall survival for assessable patients (n = 193) was 60.3% (95% CI 52.6-67.2). The total rate of peritoneal recurrence was 9.8%., Conclusion: Our new method of anvil placement for laparoscopic EJS with CS is safe and feasible with favorable survival outcomes. It eliminates the need for suturing, and will promote the clinical application of laparoscopic total gastrectomy for gastric cancer., Clinical Trials: UMIN000046119., (© 2022. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

Purpose: Anastomotic stenosis of esophagojejunostomy after total gastrectomy has a substantial impact on the postoperative quality of life of the patient. If conservative treatment doesn't work, surgical intervention should be considered. However, redoing esophagojejunostomy is an extremely demanding procedure. Especially in the case where the primary surgery was performed laparoscopically, it is an unmet problem to maintain minimal invasiveness in re-do surgery., Methods: We report 3 cases of re-do esophagojejunostomy laparoscopically performed for anastomotic stenosis after laparoscopic total gastrectomy in gastric cancer, in whom endoscopic balloon dilation did not work., Results: Each patient underwent a re-do esophagojejunostomy laparoscopically. The mean operation time was 293 min, and the mean blood loss was 56 ml. There was no anastomosis-related complication, and they were discharged from hospital on 11-16 postoperative days. At the time of discharge, oral food intake was 100% in each patient. One year after the operation, follow-up endoscopic exams showed no anastomotic stenosis., Conclusion: Re-do laparoscopic esophagojejunostomy for anastomotic stenosis after laparoscopic total gastrectomy was safely and successfully performed. It brings patients minimal invasiveness continuously from the initial surgery. Re-do laparoscopic esophagojejunostomy could be one of the options for anastomotic stenosis resistant to conservative treatment., (© 2022. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

The effect of the incident UV pump wavelength on the subsequent excited state dynamics, electronic relaxation, and ultimate dissociation of formaldehyde is studied using first principles simulation and Coulomb explosion imaging (CEI) experiments. Transitions in a vibronic progression in the à ← X̃ absorption band are systematically prepared using a tunable UV source which generates pulses centered at 304, 314, 329, and 337 nm. We find, both via ab initio simulation and experimental results, that the rate of excited state decay and subsequent dissociation displays a prominent dependence on which vibronic transition in the absorption band is prepared by the pump. Our simulations predict that nonadiabatic transition rates and dissociation yields will increase by a factor of >100 as the pump wavelength is decreased from 337 to 304 nm. The experimental results and theoretical simulations are in broad agreement and both indicate that the dissociation rate plateaus rapidly after ≈2 ps following an ultrafast sub-ps rise.

A 67-year-old man with a low-grade fever was found to have a 25-mm diameter tumor of the left hepatic umbilical portion. The tumor was accompanied by occlusion of the left portal vein. Positron emission tomography using fluorodeoxyglucose showed that the tumor had abnormally high metabolic activity. Magnetic resonance imaging revealed the left hepatic duct segmental narrowing. There was a mild elevation in serum IgG4 (206 mg/dL). Intrahepatic cholangiocarcinoma was suspected. Instead of planned hepatectomy, the patient was forced to undergo emergency surgery for biliary panperitonitis caused by intrahepatic bile duct rupture. Intraoperative ultrasonography revealed a hypoechoic tumor-like thickened Glissonean sheath and needle biopsy was performed. Histologic examination confirmed fibrous tissue with IgG4-positive plasma cell infiltration without neoplastic proliferation. He was diagnosed with IgG4-related sclerosing cholangitis (IgG4-SC) presenting hepatic inflammatory pseudotumor. After his general condition improved, he underwent left hepatectomy. Macroscopic findings showed extreme fibrosis of the Glissonean sheath of the umbilical portion, and diffuse granular lesion aggregated in the left lateral segment. Microscopic examination confirmed chronic cholangitis and dense portal fibrosis in the umbilical portion and diffuse xanthogranulomatous inflammation. This is the first case report of spontaneous rupture of the intrahepatic bile duct in patient with IgG4-SC., (© 2021. Japanese Society of Gastroenterology.)

We have used the FERMI free-electron laser to perform time-resolved photoelectron imaging experiments on a complex group of resonances near 15.38 eV in the absorption spectrum of molecular nitrogen, N 2 , under jet-cooled conditions. The new data complement and extend the earlier work of Fushitani et al. [Opt. Express 27, 19702-19711 (2019)], who recorded time-resolved photoelectron spectra for this same group of resonances. Time-dependent oscillations are observed in both the photoelectron yields and the photoelectron angular distributions, providing insight into the interactions among the resonant intermediate states. In addition, for most states, we observe an exponential decay of the photoelectron yield that depends on the ionic final state. This observation can be rationalized by the different lifetimes for the intermediate states contributing to a particular ionization channel. Although there are nine resonances within the group, we show that by detecting individual photoelectron final states and their angular dependence, we can identify and differentiate quantum pathways within this complex system.