Frequency-domain interferometry for the determination of time delay between two extreme-ultraviolet wave packets generated by a tandem undulator.

Synchrotron radiation, emitted by relativistic electrons traveling in a magnetic field, has poor temporal coherence. However, recent research has proved that time-domain interferometry experiments, which were thought to be enabled by only lasers of excellent temporal coherence, can be implemented with synchrotron radiation using a tandem undulator. The radiation generated by the tandem undulator comprises pairs of light wave packets, and the longitudinal coherence within a light wave packet pair is used to achieve time-domain interferometry. The time delay between two light wave packets, formed by a chicane for the electron trajectory, can be adjusted in the femtosecond range by a standard synchrotron technology. In this study, we show that frequency-domain spectra of the tandem undulator radiation exhibit fringe structures from which the time delay between a light wave packet pair can be determined with accuracy on the order of attoseconds. The feasibility and limitations of the frequency-domain interferometric determination of the time delay are examined.

Time domain double slit interference of electron produced by XUV synchrotron radiation.

We present a new realization of the time-domain double-slit experiment with photoelectrons, demonstrating that spontaneous radiation from a bunch of relativistic electrons can be used to control the quantum interference of single-particles. The double-slit arrangement is realized by a pair of light wave packets with attosecond-controlled spacing, which is naturally included in the spontaneous radiation from two undulators in series. Photoelectrons emitted from helium atoms are observed in the energy-domain under the condition of detecting them one by one, and the stochastic buildup of the quantum interference pattern on a detector plane is recorded.

Double-pulsed wave packets in spontaneous radiation from a tandem undulator.

We verify that each wave packet of spontaneous radiation from two undulators placed in series has a double-pulsed temporal profile with pulse spacing which can be controlled at the attosecond level. Using a Mach-Zehnder interferometer operating at ultraviolet wavelengths, we obtain the autocorrelation trace for the spontaneous radiation from the tandem undulator. The results clearly show that the wave packet has a double-pulsed structure, consisting of a pair of 10-cycle oscillations with a variable separation. We also report the characterization of the time delay between the double-pulsed components in different wavelength regimes. The excellent agreement between the independent measurements confirms that a tandem undulator can be used to produce double-pulsed wave packets at arbitrary wavelength.

Association between Malnutrition Severity and Swallowing Function in Convalescent Rehabilitation Wards: A Multi-Center Cohort Study in Malnourished Patients with Sarcopenic Dysphagia.

OBJECTIVES: To evaluate the characteristics of sarcopenic dysphagia (SD) and the prognosis of swallowing function in convalescent rehabilitation hospital patients; and to investigate the association between malnutrition severity and SD. DESIGN: A prospective, multi-center, cohort study. SETTING: We extracted registry data from the Japanese Sarcopenic Dysphagia Database, focusing on patients admitted to convalescent rehabilitation hospitals. PARTICIPANTS: A total of 207 participants were recruited and stratified according to the presence or absence of SD. Next, the participants were divided into groups based on nutrition status using the Global Leadership Initiative on Malnutrition criteria: normal nutrition, moderate malnutrition, and severe malnutrition. We also compared the outcomes between patients with SD (SD group) and those without SD (no-SD group) according to malnutrition status. MEASUREMENTS: The Food Intake LEVEL Scale (FILS) score was the outcome measure. Higher scores on the FILS indicate better swallowing function. We compared the patient characteristics between the SD and non-SD groups among all patients and then according to the severity of malnutrition. RESULTS: A total of 207 patients were recruited. 11 were diagnosed with normal nutrition, 72 with moderate malnutrition, and 124 with severe malnutrition. There were 128 participants with SD and 79 participants without SD; the prevalence of SD was 61.8%. Hip fracture was the most common disease among the SD patients (34.4%). The median time to the end of follow-up was 73.5 days for the SD group and 84.0 days for the no-SD group. There was no significant difference in the FILS score between the SD and no-SD groups, but the increase in the FILS score was significantly lower in the SD group than the no-SD group among patients with severe malnutrition after adjusting for confounding factors (age, sex, FILS at admission, BMI, cognitive functional independence measure, and care level before onset) (ß = -0.206, p = 0.011, 95% confidence interval = -0.723, -0.098). CONCLUSION: Orthopedic diseases are the most common type of disease among SD patients in convalescent rehabilitation hospitals. Swallowing dysfunction was particularly severe in malnourished patients with SD. This result suggests the importance of the definition of SD for malnourished patients. We should practice nutritional management as soon as possible in severely malnourished patients diagnosed with SD.

Effects of neuromuscular blockade on the surgical conditions of laparoscopic totally extraperitoneal inguinal hernia repair: a randomized clinical trial.

PURPOSE: Unlike other laparoscopic techniques, the peritoneum is not incised in laparoscopic totally extraperitoneal inguinal hernia repair (TEP), and the preperitoneal space is developed as the surgical field by blunt dissection and CO2 insufflation. While many studies have investigated the effect of neuromuscular blockade (NMB) on the surgical conditions and postoperative pain of laparoscopic intraperitoneal surgery, few studies have investigated those of TEP. In the present study, we investigated the effect of NMB on the surgical conditions and postoperative pain of TEP. METHODS: Forty-two adult patients scheduled for unilateral TEP under general anesthesia with remifentanil and desflurane were randomly assigned to paralyzed or non-paralyzed groups. In the paralyzed group, rocuronium doses were administered to maintain post-tetanic count at ≤ 5 during surgery. Non-paralyzed subjects were not given any rocuronium. Postoperatively, surgeon-evaluated surgical conditions, assessed using a 100-mm visual analogue scale ranging from 0 mm (not acceptable) to 100 mm (excellent), were compared between the two groups. For evaluation of postoperative pain, the time from the end of anesthesia to the initial requirement of postoperative analgesia was compared by the log-rank test. RESULTS: Median [interquartile range] score of surgical condition in the paralyzed and non-paralyzed groups were 84 [75-90] and 84 [78-87], respectively (P = 0.46). Significant differences in postoperative analgesic requirements between the two groups were not confirmed (P = 0.74). CONCLUSION: NMB did not improve the surgical conditions nor reduce postoperative pain. NMB is not routinely needed for TEP just because it is a laparoscopic procedure. CLINICAL TRIAL REGISTRATION: The trial was registered in the UMIN clinical trials registry (UMIN000029683, October 24, 2017; Principal investigator: Masafumi Fujimoto, https://upload.umin.ac.jp/cgi-open-bin/ctr/ctr_view.cgi?recptno=R000033920 ) prior to patient enrolment.

Deep Ancestral Introgression Shapes Evolutionary History of Dragonflies and Damselflies.

Introgression is an important biological process affecting at least 10% of the extant species in the animal kingdom. Introgression significantly impacts inference of phylogenetic species relationships where a strictly binary tree model cannot adequately explain reticulate net-like species relationships. Here, we use phylogenomic approaches to understand patterns of introgression along the evolutionary history of a unique, nonmodel insect system: dragonflies and damselflies (Odonata). We demonstrate that introgression is a pervasive evolutionary force across various taxonomic levels within Odonata. In particular, we show that the morphologically "intermediate" species of Anisozygoptera (one of the three primary suborders within Odonata besides Zygoptera and Anisoptera), which retain phenotypic characteristics of the other two suborders, experienced high levels of introgression likely coming from zygopteran genomes. Additionally, we find evidence for multiple cases of deep inter-superfamilial ancestral introgression. [Gene flow; Odonata; phylogenomics; reticulate evolution.].

Electron Wave Packet Interference in Atomic Inner-Shell Excitation.

We report the observation of quantum interference between electron wave packets launched from the inner-shell 4d orbital of the Xe atom. Using pairs of femtosecond radiation wave packets from a synchrotron light source, we obtain time-domain interferograms for the inner-shell excitations. This approach enables the experimental verification and control of the quantum interference between the electron wave packets. Furthermore, the femtosecond Auger decay of the inner-shell excited state is tracked. To the best of our knowledge, this is the first observation of wave packet interference in an atomic inner-shell process, and also the first time-resolved experiment on few-femtosecond Auger decay using a synchrotron light source.

Cross Sections and Asymmetry Parameters for Formic Acid in the Vacuum-Ultraviolet Energy Range.

We present an experimental and theoretical investigation of the photon interaction with formic acid in the vacuum-ultraviolet energy range. The absolute absorption cross sections and ionization efficiencies were measured in the 11.2-21.4 and 13.5-21.4 eV ranges, respectively, using a double-ion chamber technique. Photoionization and neutral-decay cross sections were derived from these results. From the present ionization cross sections and previously reported ionic dissociative branching ratios, the partial cross sections for dissociating processes were obtained. Theoretically, the photoionization cross sections and the asymmetry parameters of the photoelectron angular distributions for ionization out of the six outermost valence orbitals (10a', 2a″, 9a', 1a″, 8a', and 7a') were obtained in the energy range from near-threshold to 35 eV. For that, the Padé approximant technique along with the single-center partial-wave expansion method was applied to solve the Lippmann-Schwinger equation in the static-exchange-polarization level of approximation. This is the first theoretical investigation concerning the determination of the asymmetry parameters and photoionization cross sections of formic acid in the vacuum-ultraviolet energy range. Comparison is made between our results and the previous ones.

Long-Term Outcomes of the WEB Device for Treatment of Wide-Neck Bifurcation Aneurysms.

BACKGROUND AND PURPOSE: Treatment of wide-neck bifurcation aneurysms using endovascular therapy is still challenging even with the development of treatment devices. The purpose of this investigation was to assess the safety and efficacy of treatment with a Woven EndoBridge (WEB) device for wide-neck bifurcation aneurysms. MATERIALS AND METHODS: All patients treated with a WEB device at our institution between May 2009 and November 2016 were retrospectively evaluated. Clinical and imaging evaluation, aneurysm occlusion status, and modified Rankin scale score were analyzed 1 day after treatment and in the short- (<6 months), mid- (<24 months), and long-term (>24 months) follow-up periods. RESULTS: Forty-one cases of wide-neck aneurysms were analyzed in this study. Overall, 78.8% of the aneurysms had complete occlusion in the last follow-up, and 19.5% required retreatment with additional endovascular devices. A good clinical outcome (modified Rankin scale: 0-2) was obtained in 95.1% of the patients, and the overall treatment-related morbidity and mortality rates were 2.4% and 0.0%, respectively. The mean follow-up time was 15.3 ± 13.5 months. CONCLUSIONS: The results obtained in this study suggest that treatment of wide-neck bifurcation aneurysms with a WEB device is feasible with an acceptable safety and efficacy rate.

Developing classification criteria for skin-predominant dermatomyositis: the Delphi process.

BACKGROUND: The European League Against Rheumatism/American College of Rheumatology classification criteria for inflammatory myopathies are able to classify patients with skin-predominant dermatomyositis (DM). However, approximately 25% of patients with skin-predominant DM do not meet two of the three hallmark skin signs and fail to meet the criteria. OBJECTIVES: To develop a set of skin-focused classification criteria that will distinguish cutaneous DM from mimickers and allow a more inclusive definition of skin-predominant disease. METHODS: An extensive literature review was done to generate items for the Delphi process. Items were grouped into categories of distribution, morphology, symptoms, antibodies, histology and contextual factors. Using REDCap™, participants rated these items in terms of appropriateness and distinguishing ability from mimickers. The relevance score ranged from 1 to 100, and the median score determined a rank-ordered list. A prespecified median score cut-off was decided by the steering committee and the participants. There was a pre-Delphi and two rounds of actual Delphi. RESULTS: There were 50 participating dermatologists and rheumatologists from North America, South America, Europe and Asia. After a cut-off score of 70 during the first round, 37 of the initial 54 items were retained and carried over to the next round. The cut-off was raised to 80 during round two and a list of 25 items was generated. CONCLUSIONS: This project is a key step in the development of prospectively validated classification criteria that will create a more inclusive population of patients with DM for clinical research. What's already known about this topic? Proper classification of patients with skin-predominant dermatomyositis (DM) is indispensable in the appropriate conduct of clinical/translational research in the field. The only validated European League Against Rheumatism/American College of Rheumatology criteria for idiopathic inflammatory myopathies are able to classify skin-predominant DM. However, a quarter of amyopathic patients still fail the criteria and does not meet the disease classification. What does this study add? A list of 25 potential criteria divided into categories of distribution, morphology, symptomatology, pathology and contextual factors has been generated after several rounds of consensus exercise among experts in the field of DM. This Delphi project is a prerequisite to the development of a validated classification criteria set for skin-predominant DM.

Controlling the Orbital Alignment in Atoms Using Cross-Circularly Polarized Extreme Ultraviolet Wave Packets.

We report on the use of pairs of 10-cycle extreme ultraviolet wave packets with attosecond-controlled spacing emitted by individual relativistic electrons within an electron bunch passing through a tandem undulator. Based on the temporal coherent control technique with circular polarization, we succeeded in controlling the excited state alignment in the photoexcitation of helium atoms, which we verified through the observation of oscillation in fluorescence yield depending on the attosecond-controlled delay time. Our work demonstrates the potential of undulator radiation for the generation of longitudinally coherent wave packets suitable for attosecond coherent control, an application which has hitherto been hidden in the incoherent nature of the radiation pulse emitted by a bunch of electrons.

Coherent control in the extreme ultraviolet and attosecond regime by synchrotron radiation.

Quantum manipulation of populations and pathways in matter by light pulses, so-called coherent control, is currently one of the hottest research areas in optical physics and photochemistry. The forefront of coherent control research is moving rapidly into the regime of extreme ultraviolet wavelength and attosecond temporal resolution. This advance has been enabled by the development of high harmonic generation light sources driven by intense femtosecond laser pulses and by the advent of seeded free electron laser sources. Synchrotron radiation, which is usually illustrated as being of poor temporal coherence, hitherto has not been considered as a tool for coherent control. Here we show an approach based on synchrotron radiation to study coherent control in the extreme ultraviolet and attosecond regime. We demonstrate this capability by achieving wave-packet interferometry on Rydberg wave packets generated in helium atoms.

Publisher Correction: Electron magnetic reconnection without ion coupling in Earth's turbulent magnetosheath.

Change history: In this Letter, the y-axis values in Fig. 3f should go from 4 to -8 (rather than from 4 to -4), the y-axis values in Fig. 3h should appear next to the major tick marks (rather than the minor ticks), and in Fig. 1b, the arrows at the top and bottom of the electron-scale current sheet were going in the wrong direction; these errors have been corrected online.